WSAVA Guidelines for the vaccination of dogs and cats



# Introduction
The WSAVA Vaccination Guidelines Group (VGG) was convened in 2006 with the aim of producing global vaccination guidelines for dogs and cats that would consider international differences in economic and societal factors that impact on the keeping of these small companion animals. The WSAVA guidelines are therefore intended to be much broader in scope than those produced for North America by the American Academy of Feline Practitioners [bib_ref] AAFP Feline Vaccination Advisory Panel report, Scherk [/bib_ref] and the American Animal Hospital Association [bib_ref] AAHA canine vaccination guidelines, Welborn [/bib_ref] or for Europe by the Advisory Board on Cat Diseases [bib_ref] Matrix vaccination guidelines: ABCD recommendations for indoor/outdoor cats, rescue shelter cats and..., Hosie [/bib_ref]. The first WSAVA guidelines were published in 2007 ) and these were updated in 2010 [bib_ref] Guidelines for the vaccination of dogs and cats, Day [/bib_ref] with an accompanying document written for the owners and breeders of pet dogs and cats. Between 2011 and 2013, the VGG focused on dog and cat infectious disease and vaccinology on the Asian continent and produced regional recommendations on aspects of vaccination for Asian practitioners. In 2014 and 2015, the VGG has worked on updating the global canine and feline vaccination guidelines as now presented in this document.
The format and much of the content of this 2015 revision remain similar to the guidelines published in 2010; however, specific changes in the current document include:
of mortality in small animals. Although it is difficult to obtain accurate figures, even in developed countries it is estimated that only 30-50% of the pet animal population is vaccinated, and this is significantly less in developing nations. The global economic recession post-2008 has had further impact on the uptake of preventive healthcare by pet owners in developed countries and survey data suggests a recent decline in vaccination [bib_ref] Survey suggests many pets do not receive preventive healthcare, Anon [/bib_ref].
In small animal medicine, we have been slow to grasp the concept of 'herd immunity' -that vaccination of individual pet animals is important, not only to protect the individual, but to reduce the number of susceptible animals in the regional population, and thus the prevalence of disease. Herd immunity related to use of core vaccines that provide a long (many years) DOI is highly dependent on the percentage of animals in the population vaccinated and not the number of vaccinations that occur annually. Therefore, every effort should be made to vaccinate a higher percentage of cats and dogs with the core vaccines. It is simply not possible to induce 'better' immunity in an individual animal by giving repeated vaccinations, i.e. a dog receiving a core MLV vaccine every 3 years will be equally well protected compared with one receiving the same vaccine annually [bib_ref] Serum antibody titres to canine parvovirus, adenovirus and distemper virus in dogs..., Bohm [/bib_ref] [bib_ref] Duration of serologic response to five viral antigens in dogs, Mouzin [/bib_ref] [bib_ref] Duration of serological response to canine parvovirus-type 2, canine distemper virus, canine..., Mitchell [/bib_ref] [EB1], but this may not necessarily be the case for feline core vaccines (see below).
In recent years the re-emerging concept of 'One Health' has also impacted on the field of vaccinology. The management of infectious diseases through the collaborative interaction of human medical, animal and environmental healthcare professionals provides a rational and cost-effective goal at a time when the majority of newly emergent human infectious diseases is proposed to derive from wild or domestic animal sources [bib_ref] The evolution of One Health: a decade of progress and challenges for..., Gibbs [/bib_ref]. The WSAVA has embraced the One Health concept with establishment of a One Health Committee in 2010 [bib_ref] Guidelines for the vaccination of dogs and cats, Day [/bib_ref] , the work of which overlaps with that of the VGG when tackling the major small companion animal zoonoses of canine rabies and leishmaniosis.
A second major concept regarding vaccination of dogs and cats has been the recognition that we should aim to reduce the 'vaccine load' on individual animals in order to minimize the potential for adverse reactions to vaccine products and reduce the time and financial burden on clients and veterinarians of unjustified veterinary medical procedures. For these reasons we have seen the development of vaccination guidelines based on a rational analysis of the vaccine requirements for each pet, and the proposal that vaccines be considered 'core' and 'non-core' in nature. To an extent this categorization of products has been based on available scientific evidence and personal experience -but concerted effort to introduce effective companion animal disease surveillance on a global scale would provide a more definitive basis on which to recommend vaccine usage [bib_ref] Surveillance of zoonotic infectious diseases transmitted by small companion animals, Day [/bib_ref]. In parallel with the categorization of vaccines has been the push towards marketing products with extended DOI, to reduce the unnecessary administration of vaccines and thereby further improve vaccine safety. Both of these changes have necessitated a frame-shift in the mind-set of veterinary practitioners, which is now becoming the accepted norm in many countries.
The following VGG guidelines are prepared when considering the optimum model of committed pet owners, willing and able to bring their animals to the veterinarian, for the full recommended course of vaccination. The VGG is aware that there are less committed or able pet owners in every country and there are countries where severe financial or societal constraints often determine the nature of the vaccine course that can be administered. In situations where, for example, a decision must be made that an individual pet may have to receive only a single core vaccination during its lifetime, the VGG would emphasise that this should optimally be given at a time when that animal is most capable of responding immunologically, i.e. at greater than 16 weeks of age.
The VGG has additionally considered vaccination in the shelter situation. The guidelines that we have proposed are those that we consider provide the optimum level of protection for these highly susceptible animals. The VGG also recognises that many shelters run with limited financial support which may constrain the extent of vaccination used. The minimum vaccination protocol in this situation would be a single administration of core vaccines at or before the time of admission to the shelter.
This document seeks to address these current issues in canine and feline vaccinology, and to suggest practical measures by which the veterinary profession may move further towards more rational use of vaccines in these species. The most important message of the VGG is therefore encapsulated in the following statement:
We should aim to vaccinate every animal with core vaccines. Non-core vaccines should be given no more frequently than is deemed necessary.

## Types of vaccine
Before discussing specific vaccination guidelines, a brief review of the types of small companion animal vaccine available is justified. Vaccines may be considered simply as either 'infectious' or 'non-infectious' in nature.
Most infectious vaccines used in dogs and cats contain organisms that are attenuated to reduce virulence (i.e. 'modified live virus' or attenuated vaccines), but the organisms are intact and viable and induce immunity by inducing low-level infection and replicating within the animal, without producing significant tissue pathology or clinical signs of infectious disease. Infectious vaccines have the advantage of more effectively inducing immunity at relevant anatomical sites when administered parenterally and are more likely to induce robust cell-mediated and humoral (antibody-mediated) immunity. Some infectious vaccines are administered Journal of Small Animal Practice - Vol 57 - January 2016 -  2016 WSAVA E7 directly to mucosal sites (i.e. intranasal or oral vaccines) where they are even more effective at inducing relevant protective mucosal immunity. Some recombinant vectored vaccines (i.e. a live vector organism carrying genetic material encoding an antigen from the target pathogen) may also be considered 'infectious'; however, the vector organism is not relevant to, or pathogenic in, the dog or cat. When administered to an animal that lacks maternally-derived antibody (MDA) an infectious vaccine will generally induce protection with a single dose.
Non-infectious vaccines (also known as killed or inactivated vaccines and including subunit and naked DNA vaccines) contain an inactivated but antigenically intact virus or organism, or a natural or synthetic antigen derived from that virus or organism, or the DNA that can encode such an antigen. Non-infectious agents are unable to infect, replicate or induce pathology or clinical signs of infectious disease. They generally require an adjuvant to increase their potency and usually require multiple doses (even in an adult animal) to induce protection. Non-infectious vaccines are administered parenterally and may be less likely to induce both cellmediated and humoral immunity and generally have a shorter DOI compared with infectious vaccines.

## Canine vaccination guidelines

## Vaccination of individual dogs
The Basic Immunization Schedule Guidelines and recommendations for core (recommended), non-core (optional) and not recommended vaccines for the general veterinary practice are given in . The VGG considers that a core vaccine is one that all dogs throughout the world must receive, at recommended intervals, in order to provide life-long protection against infectious diseases of global significance. The core vaccines for the dog are those that confer protection against infection by canine distemper virus (CDV), canine adenovirus (CAV; types 1 and 2) and canine parvovirus type 2 (CPV-2) and its variants. The VGG recognizes that particular countries will identify additional vaccines that they consider core. A particular example of a vaccine that may be considered core in only some countries is that against rabies virus. In a geographical area in which this infection is endemic, all dogs should be vaccinated routinely for the protection of both the pet and human populations. The VGG strongly endorses the joint statement of the WSAVA One Health Committee and the International Organisation for Animal Health (OIE) which sets a target for global elimination of canine rabies by 2030 [bib_ref] WSAVA and OIE call for action on rabies, Anon [/bib_ref]. In many countries, rabies vaccination is a legal requirement, and is generally also required for international pet travel.
Non-core vaccines are those for which use is determined on the basis of the geographical and lifestyle exposure risks of the individual and an assessment of risk-benefit ratios (i.e. the risk of being unvaccinated and susceptible or the risk of being vaccinated and developing an adverse reaction versus the benefit of being protected against the infection in question). Not recommended vaccines are those for which there is little scientific justification (insufficient evidence base) for their use.
Puppy Vaccination and the 6-or 12-Month Booster Most puppies are protected by MDA in the first weeks of life. In most puppies, passive immunity will have waned by 8-12 weeks of age to a level that allows active immunization. Puppies with poor MDA may be vulnerable (and capable of responding to vaccination) at an earlier age, while others may possess MDA at such high titres that they are incapable of responding to vaccination until 12 weeks of age [bib_ref] Untersuchung der wirksamkeit von parvovirussimpfstoffen und der effektivitat zweier impfschemata, Friedrich [/bib_ref]. No single primary vaccination policy will therefore cover all possible situations. The recommendation of the VGG is for initial core vaccination at 6-8 weeks of age, then every 2-4 weeks until 16 weeks of age or older. Therefore the number of puppy primary core vaccinations will be determined by the age at which vaccination is started and the selected interval between vaccinations. Possible schedules are outlined in [fig_ref] Table 5: weeks, 13 weeks, 17 weeks then 26 or 52 weeks [/fig_ref]. By this recommendation, when vaccination is started at 6 or 7 weeks of age, a course of four primary core vaccines would be administered with a 4-week interval, but only three would be required with an 8-or 9-week start and a similar 4-week interval.
In contrast, many vaccine datasheets continue to recommend an initial course of two injections of core vaccine. Some products are also licensed with a '10 week finish' designed such that the second of two core vaccinations is given at 10 weeks of age. The rationale behind this protocol is to permit 'early socialization' of puppies while diminishing the risk of infectious diseases. The VGG recognizes that early socialization is essential to the behavioural development of dogs [bib_ref] Comparison of early socialization practices used for litters of small-scale registered dog..., Korbelik [/bib_ref] [EB1]. Where such protocols (i.e. 'puppy classes') are adopted, vigilance should still be maintained by the owner -allowing restricted exposure of their puppy to controlled areas and only to other puppies and adults that appear healthy and are fully vaccinated. In particular 'puppy classes' should be held in venues away from the veterinary practice. Alternatively, if it is decided that veterinary premises must be used, the floors should be cleaned and disinfected before each class and the classes held in an area not highly trafficked by dogs of unknown vaccination or disease status. A recent US study has shown the minimal risk for CPV-2 amongst vaccinated puppies attending socialization classes [bib_ref] Frequency of CPV infection in vaccinated puppies that attended puppy socialization classes, Stepita [/bib_ref]. The VGG recommends that whenever possible the last of the puppy primary series of core vaccines be given at 16 weeks of age or older .
An integral part of core vaccination of puppies is the 'booster' vaccine that has traditionally been given either at 12 months of age or 12 months after the last of the primary series of puppy vaccines. The main aim of this vaccine is to ensure that a protective immune response develops in any dog that may have failed to respond to any of the vaccines in the primary core series, rather than necessarily 'boosting' the immune response. The delivery of this vaccine at 12 months of age is likely to have been chosen historically as a convenient time to request the owner to attend the practice for a first annual health check. This therefore implies that should an individual puppy fail to respond to any of the primary core vaccinations, that puppy may be unprotected until it receives this 12-month vaccine. This might account for occurrences of infectious disease (e.g. canine parvoviral enteritis) in a proportion of vaccinated puppies at less than 12 months of age. The VGG has re-evaluated this practice and now suggests that veterinarians might wish to reduce this possible window of susceptibility by bringing forward this vaccine from 52 weeks to 26 weeks of age (or indeed at any time point between 26 and 52 weeks of age; however, 26 weeks of age provides a convenient timing). This practice will require that pet owners clearly understand why this is recommended, because as indicated in [fig_ref] Table 5: weeks, 13 weeks, 17 weeks then 26 or 52 weeks [/fig_ref] , adopting such a protocol will mean that vaccination started in a 6 or 7 week old puppy, might now entail up to five vaccine visits in the first 6 months of life. For core vaccines, after a 26 week 'booster', another core vaccine would not be required for at least another 3 years. This new recommendation for vaccination at 6 months of age as an alternative to vaccination at about 1 year of age is certainly not mutually exclusive to, and does not preclude, a 1-year or 16-month 'first annual health check'. Many veterinarians are understandably keen to check the animals under their care at around the time they reach skeletal maturity.

## Revaccination of adult dogs
Dogs that have responded to vaccination with MLV core vaccines maintain a solid immunity (immunological memory) for many years in the absence of any repeat vaccination [bib_ref] Serum antibody titres to canine parvovirus, adenovirus and distemper virus in dogs..., Bohm [/bib_ref] [bib_ref] Duration of serologic response to five viral antigens in dogs, Mouzin [/bib_ref] [bib_ref] Duration of immunity for canine and feline vaccines: a review, Schultz [/bib_ref] [bib_ref] Duration of serological response to canine parvovirus-type 2, canine distemper virus, canine..., Mitchell [/bib_ref] [EB1]. Following the 26 or 52 week booster, subsequent revaccinations are given at intervals of 3 years or longer. It should be emphasized that triennial adult revaccination does not generally apply to killed core vaccines (except for rabies) nor to the non-core vaccines, and particularly not to vaccines containing bacterial antigens. Thus Leptospira, Bordetella and Borrelia (Lyme disease) products, but also parainfluenza virus components, require more frequent boosters for reliable protection [bib_ref] A review of canine parainfluenza virus infection in dogs, Ellis [/bib_ref] [bib_ref] A new tetravalent canine leptospirosis vaccine provides at least 12 months immunity..., Klaasen [/bib_ref] [bib_ref] How well do vaccines for Bordetella bronchiseptica work in dogs? A critical..., Ellis [/bib_ref] [bib_ref] European consensus statement on leptospirosis in dogs and cats, Schuller [/bib_ref].
Therefore an adult dog may, according to these guidelines, still be revaccinated annually, but the components of these vaccinations may differ each year. Typically, core vaccines are currently administered triennially, with chosen non-core products being given annually. The VGG is aware that in some countries only multi-component products containing core and non-core combinations are available. The VGG would encourage manufacturers to make a full range of reduced-component vaccines (or at least separate core and non-core vaccines [bib_ref] Duration of serological response to canine parvovirus-type 2, canine distemper virus, canine..., Mitchell [/bib_ref] available wherever possible.
An adult dog that had received a complete course of core vaccinations as a puppy, including a 26 or 52 week booster, but that may not have been vaccinated regularly as an adult, requires only a single dose of MLV core vaccine to boost immunity [bib_ref] Duration of serologic response to five viral antigens in dogs, Mouzin [/bib_ref] [bib_ref] Duration of serological response to canine parvovirus-type 2, canine distemper virus, canine..., Mitchell [/bib_ref]. Similarly, an adopted adult dog (or puppy over 16 weeks of age) of unknown vaccination history requires only a single dose of MLV core vaccine to engender a protective immune response. Many vaccine datasheets will advise in these circumstances that the dog requires two vaccinations (as for a puppy), but this practice is unjustified and contrary to fundamental immunological principles . Note again, that this does not apply to non-core vaccines, many of which will require two doses in an adult dog. Particular mention should be made of canine rabies vaccines. The VGG recommends that in any country in which canine rabies is endemic, vaccination of dogs should be strongly recommended to clients by veterinarians, even if not required by law. Revaccination intervals for canine rabies are often mandated by law. Internationally available killed rabies vaccines were initially produced with a licensed 1-year DOI and so statutes required annual revaccination. These same products now carry a 3-year DOI in many countries, where laws have been modified to incorporate this change. However, in some countries the legal requirement is at odds with the vaccine license and in others neither the vaccine license, nor the law, has been changed. Finally, some countries also have locally-manufactured rabies vaccines with a 1-year DOI that most likely cannot safely be extended to 3 years. Veterinarians should be mindful of the law, but where they have access to a product that confers a minimum of 3-years immunity, national associations might lobby to have the laws changed to match the current scientific evidence.
Serological Testing to Monitor Immunity to Canine Vaccines Since publication of the 2010 guidelines there have been advances in the availability of rapid and simple in-practice serological test kits that can detect the presence of protective antibody specific for CDV, CAV and CPV-2 in individual dogs. These test kits complement the traditional laboratory-based modalities (i.e. virus neutralization and haemagglutination inhibition test) that remain the 'gold standards' for serological testing. Two commercially produced test kits are available and have been applied and validated in the practice and shelter setting [bib_ref] Comparison of two assays for detection of antibodies against canine parvovirus and..., Gray [/bib_ref] [bib_ref] Prevalence of positive antibody test results for canine parvovirus (CPV) and canine..., Litster [/bib_ref]. These test kits have proven popular with veterinarians who wish to be able to offer their clients an alternative to routine core revaccination at 3-yearly intervals, but the kits remain relatively expensive and unfortunately, at present, testing costs more than a dose of vaccine. A negative test result indicates that the dog has little or no antibody, and that revaccination is recommended. Some seronegative dogs are in fact immune (false-negative) and their revaccination would be unnecessary because they would make a rapid and substantial anamnestic response to vaccination [bib_ref] Duration of serologic response to five viral antigens in dogs, Mouzin [/bib_ref]. However, such dogs cannot be detected readily and an animal with a negative result, regardless of the test used, should be considered as having no antibody and potentially susceptible to infection. In contrast, a positive test result would lead to the conclusion that revaccination is not required.
Monitoring serum antibody specific for canine rabies is not generally used in the same manner for determining revaccination requirements as these are mandated by law. Laboratory testing for a protective rabies antibody titre (considered as more than 05 IU/ml) is required for international pet travel. Rabies serology is only performed by recognized reference laboratories.
Serological testing for CDV, CAV and CPV-2 has application for determining protective immunity in the puppy, for informing revaccination intervals in adult dogs and in management of infectious disease outbreaks in shelters.
A dedicated owner may wish to confirm that a puppy is protected after the course of primary vaccinations when these are completed at 16 weeks or older . A serum sample taken at least 4 weeks after the final vaccination may be tested. This interval will ensure that MDA is no longer present and that even 'slow responder' puppies have seroconverted. A seropositive puppy would not require a 26 or 52 week booster and could next receive core vaccine 3 years later. Seronegative puppies should be revaccinated and retested. If the pup again tests negative, it should be considered a non-responder that is possibly incapable of developing protective immunity.
Testing for antibody is presently the only practical way to ensure that a puppy's immune system has recognized the vaccinal antigen. Vaccines may fail to induce protective immunity in a puppy for various reasons:
(1) MDA neutralizes the vaccine virus This is the most common reason for vaccination failure. However, when the last vaccine dose is given 16 weeks of age or older, MDA should have decreased to a low level [bib_ref] Untersuchung der wirksamkeit von parvovirussimpfstoffen und der effektivitat zweier impfschemata, Friedrich [/bib_ref] [EB1], and active immunization will succeed in most puppies.
(2) The vaccine is poorly immunogenic Poor immunogenicity may reflect a range of factors from the stage of vaccine design and manufacture to administration to the animal. For example, the virus strain, its passage history or production errors in the manufacture of a particular batch of product may be a cause of vaccine failure. In reality, such effects rarely affect vaccines produced by large, well-established manufacturers that market their vaccines internationally. These manufacturers have strict requirements from government regulatory agencies for batch potency testing before release. Post-manufacture factors such as incorrect storage or transportation (interrupted cold chain) and handling (disinfectant use) of the vaccine in the veterinary practice, may result in inactivation of an MLV product. The VGG has recognized that such 'vaccine husbandry' remains an issue in many countries and has included some simple guidelines in .
(3) The animal is a poor responder (its immune system intrinsically fails to recognize the vaccinal antigens) If an animal fails to develop an antibody response after repeated revaccination, it should be considered a genetic non-responder. Because immunological non-responsiveness is genetically controlled in other species, certain breeds of dogs have been suspected to be poor-responders. It is believed (but unproven) that the high susceptibility to CPV-2 recognized in certain Rottweilers and Dobermanns during the 1980s (regardless of their vaccination history) relates in part to a high prevalence of non-responders [EB4]. In the USA today, these two breeds seem to have no greater numbers of non-responders to CPV-2 than other breeds, possibly because carriers of the genetic trait may have died from CPV-2 infection. Some dogs of these breeds may be low or non-responders to other antigens. For example, in the UK and Germany, the non-responder phenotype remains prevalent amongst Rottweilers [EB3] for CPV-2 and recent studies have shown this breed to have a higher proportion of animals failing to achieve the titre of rabies antibody required for pet travel [bib_ref] Factors influencing the antibody response of dogs vaccinated against rabies, Kennedy [/bib_ref] [EB1]. Some broad estimates have been made of the proportion of genetic non-responders in the canine population, these being: 1 in every 5,000 dogs for CDV, 1 in every 100,000 dogs for CAV and 1 in every 1,000 dogs for CPV-2 [EB4].
Serological Testing to Determine the Duration of Immunity (DOI) Antibody tests can be used to demonstrate the DOI after vaccination with core vaccines. It is known that a large majority of dogs maintain protective antibody against CDV, CPV-2, CAV-1 and CAV-2 for many years and numerous experimental studies support this observation [bib_ref] Serum antibody titres to canine parvovirus, adenovirus and distemper virus in dogs..., Bohm [/bib_ref] [bib_ref] Duration of serologic response to five viral antigens in dogs, Mouzin [/bib_ref] [bib_ref] Duration of immunity for canine and feline vaccines: a review, Schultz [/bib_ref] [bib_ref] Duration of serological response to canine parvovirus-type 2, canine distemper virus, canine..., Mitchell [/bib_ref] [EB1]. Therefore, when antibody is absent (irrespective of the serological test used) the dog should be revaccinated unless there is a medical reason for not so doing, even though some will be protected by immunological memory. Antibody determinations to other vaccine components are of limited or no value because of the short time period these antibodies persist (e.g. Leptospira products) or the lack of correlation between serum antibody and protection (e.g. Leptospira and canine parainfluenza) [bib_ref] Humoral immune response of dogs after vaccination against leptospirosis measured by an..., Hartman [/bib_ref] [bib_ref] Duration of immunity in dogs vaccinated against leptospirosis with a bivalent inactivated..., Klaasen [/bib_ref] [bib_ref] A review of canine parainfluenza virus infection in dogs, Ellis [/bib_ref] 
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The VGG recognizes that at present such serological testing might be relatively expensive. However, the principles of 'evidencebased veterinary medicine' suggest that testing for antibody status (for either puppies or adult dogs) should be better practice than simply administering a vaccine booster on the basis that this would be 'safe and cost less'.

## Passive immunization
While vaccination (i.e. active immunization) dominates infectious disease prevention, passive immunization continues to be used in the treatment of infectious disease in many countries.
Although virus infections trigger both cellular and humoral immunity, it is mainly the antibody response that contributes to the reduction of viral load and recovery. In many virus infections, antibody levels are therefore taken as correlates of protection. During viraemia, pre-existing or injected antibodies directed against surface structures of virions bind to the particles, neutralize their infectivity and prepare them for removal. Therapeutically, most serum or immunoglobulin preparations used in passive immunization are injected subcutaneously (because they are from a different animal species) and quickly reach the circulation. Not unexpectedly, intravenous infusions of plasma or serum (from the same species) have been found to work as well. In local infections, such as those initiated by the bite of a rabid carnivore, post-exposure antibody prophylaxis has also proven invaluable in human medicine. Human rabies immune globulin provides rapid protection when given on the first day of the post-exposure prophylaxis regimen. As much as possible of the preparation is infiltrated into and around the wound, and may be given intramuscularly at a site distant from the rabies vaccine, which is applied simultaneously.
In companion animal practice, preventive active immunization is so commonplace that serum prophylaxis/therapy is considered only under exceptional circumstances (e.g. when a dog is presented with distemper or a cat is presented with panleukopenia, or during a disease outbreak in a kennel/cattery). There is still a market for serum and immunoglobulin products, and companies producing them exist in the USA, Germany, the Czech Republic, Slovakia, Russia and Brazil. The preparations are either of homologous or heterologous (e.g. horse) origin, are polyvalent (directed against several viruses) and consist of sera or their immunoglobulin fraction.
Despite the availability of such products, the VGG recommends that they be used conservatively, and only after careful consideration. In the case of an outbreak of CDV infection in a kennel, it is much safer and more effective to vaccinate all dogs with CDV vaccine rather than give immune serum (see below and [fig_ref] Table 7: Use of Serological Testing in a Shelter Infectious Disease Outbreak [/fig_ref] [bib_ref] Effect of vaccination with recombinant canine distemper virus vaccine immediately before exposure..., Larson [/bib_ref] [EB1]. In such a situation it has previously been recommended that MLV vaccines be administered intravenously (off-label) rather than subcutaneously or intramuscularly, but there is little evidence that this practice provides more effective or rapid protection than subcutaneous or intramuscular injection. Administration of CDV vaccines by any of those routes will provide protection from severe disease and death immediately or very Journal of Small Animal Practice - Vol 57 - January 2016 -  2016 WSAVA E11 shortly after vaccination. In this instance the vaccine does not prevent infection, but instead it protects from severe disease (especially from neurological disease) so the animal will survive and will subsequently be immune for life.
In the case of a cattery outbreak of FPV infection, or a kennel outbreak of CPV-2 infection, a recent study has shown that if immune plasma is given after clinical signs appear, there is no benefit in reduction of morbidity or mortality [bib_ref] Clinical evaluation of a single dose of immune plasma for treatment of..., Bragg [/bib_ref] [EB1]. However, this work has been criticised because only a small volume (12 ml) of immune plasma was given to each puppy in this study. Much larger volumes (66-11 ml/kg) are routinely used by researchers and practitioners and these large doses are believed by some experienced clinicians and investigators to have efficacy [bib_ref] Immune plasma for treatment of parvoviral gastroenteritis, Dodds [/bib_ref] [EB4]. In order to have a maximal beneficial effect, immune serum or plasma must be given after infection, but prior to the onset of clinical signs. In this case administration of immune serum or plasma is best provided within 24-48 hours after infection and a large amount of high titred serum or plasma is required. The serum or plasma must be given parenterally (e.g. subcutaneously, intravenously or intraperitoneally) and not orally. There is no benefit from oral administration even when treatment is started prior to infection.
An important consideration in a shelter situation is the relative cost of these commercial products. An alternative practice that is sometimes used in a shelter situation is to collect serum or plasma from animals in the shelter that have survived disease or have been recently vaccinated. However, this practice carries risk as the serum will not necessarily have been screened for transmissible pathogens (e.g. haemoparasites or feline retroviruses). Serological testing provides a more effective approach to controlling disease outbreaks in a shelter situation (see below and [fig_ref] Table 7: Use of Serological Testing in a Shelter Infectious Disease Outbreak [/fig_ref].

## An update on new canine vaccines
Since publication of the 2010 WSAVA guidelines, newly introduced vaccines include a Bordetella bronchiseptica vaccine for oral administration [bib_ref] Evaluation of efficacy of oral administration of Bordetella intranasal vaccine when used..., Hess [/bib_ref] [bib_ref] How well do vaccines for Bordetella bronchiseptica work in dogs? A critical..., Ellis [/bib_ref] and, globally, an increased range of Leptospira vaccines containing multiple, geographically relevant serogroups [bib_ref] The evolution of One Health: a decade of progress and challenges for..., Gibbs [/bib_ref] [bib_ref] European consensus statement on leptospirosis in dogs and cats, Schuller [/bib_ref]. These products are described in .
A vaccine against canine influenza virus (CIV) infection is licensed only in the USA [bib_ref] Evaluation of the efficacy of a canine influenza virus (H3N8) vaccine in..., Deshpande [/bib_ref] [bib_ref] Efficacy of the canine influenza virus H3N8 vaccine to decrease severity of..., Larson [/bib_ref]. The influenza A subtype H3N8 has been well recognized as a cause of respiratory disease in North American dogs that are housed together [bib_ref] Transmission of equine influenza virus to dogs, Crawford [/bib_ref] [bib_ref] Influenza A virus (H3N8) in dogs with respiratory disease, Payungporn [/bib_ref] [bib_ref] Canine H3N8 influenza virus infection in dogs and mice, Castleman [/bib_ref] , but to date only sporadic outbreaks have been recognized and reported elsewhere [bib_ref] Transmission of equine influenza virus to dogs, Crawford [/bib_ref] [bib_ref] Transmission of equine influenza virus to English foxhounds, Daly [/bib_ref] [bib_ref] Influenza virus transmission from horses to dogs, Kirkland [/bib_ref] [bib_ref] A population prevalence study on influenza infection in dogs in Southern Italy, Pratelli [/bib_ref] [bib_ref] Prevalence of canine influenza virus A (H3N8) in dogs in Germany, Schulz [/bib_ref]. The CIV vaccine contains inactivated virus and is administered to pups from 6 weeks of age with a second dose 2-4 weeks later and then annual revaccination. Immunity develops approximately 7 days after the second dose. The vaccine is considered non-core and is recommended only for at-risk dogs in North America that are likely to be exposed as part of their lifestyle [bib_ref] Prevalence of and exposure factors for seropositivity to H3N8 canine influenza virus..., Anderson [/bib_ref] [EB1]. At the time of writing, a local outbreak of canine influenza attributed to virus of the H3N2 subtype was reported from the Chicago and Wisconsin region of the USA and a conditionally licensed vaccine against this subtype has been released.
The first canine immunotherapeutic vaccine for malignant melanoma was licensed in 2010. This product comprises the human tyrosinase gene incorporated into a plasmid (a 'naked DNA' vaccine) that is repeatedly delivered by use of a high-pressure transdermal injection device. The vaccine is used as an adjunctive treatment in dogs with oral melanomas and induces an immune response to this melanoma target antigen. Initial studies showed that the median survival time of dogs with grade II-IV melanoma increased to 389 days (from an expected survival of 90 days) [bib_ref] Development of a xenogeneic DNA vaccine program for canine malignant melanoma at..., Bergman [/bib_ref] , but more recent studies have shown a lesser effect [bib_ref] Safety and efficacy of a xenogeneic DNA vaccine encoding for human tyrosinase..., Grosenbaugh [/bib_ref] [bib_ref] A retrospective analysis of the efficacy of Oncept vaccine for the adjunct..., Ottnod [/bib_ref] [EB1]. The vaccine is also available in Europe and, as in the USA, is limited to use by recognized veterinary oncology specialists.
Two licensed vaccines for canine leishmaniosis were until recently available in Brazil, where leishmaniosis is a disease of major importance to the canine and human populations. The first of these is a subunit product containing GP63 of Leishmania donovani (also known as the 'fucose mannose ligand'; FML) in saponin adjuvant. It is considered to induce antibody that blocks the transmission of the organism from the dog to the sandfly vector by preventing binding of Leishmania to the midgut of the sand fly and has been extensively evaluated in immunological and epidemiological field studies [bib_ref] Decrease of the incidence of human and canine visceral leishmaniasis after dog..., Palatnik-De-Sousa [/bib_ref] [bib_ref] One health: the global challenge of epidemic and endemic leishmaniasis, Palatnik-De-Sousa [/bib_ref] [EB1]. However, this product has been recently withdrawn from the Brazilian market. The second Brazilian vaccine contains the A2 antigen from L. donovani in saponin adjuvant. This vaccine is reported to induce similar protective effects in vaccinated dogs (i.e. with respect to seroconversion, prevention of infection and clinical signs and transmission to the vector) to the FML vaccine, when both were compared in a natural exposure field trial in an endemic area over an 11 month period. Dogs vaccinated with the A2 vaccine developed a lesser humoral immune response but showed a greater frequency of adverse events post vaccination .
A European Leishmania vaccine for dogs was introduced in 2011 [bib_ref] Vaccination with LiESP/QA-21 (CaniLeish) reduces the intensity of infection in Phlebotomus perniciosus..., Bongiorno [/bib_ref]. This vaccine contains excretory-secretory antigens of Leishmania infantum in adjuvant. The vaccine is used in seronegative dogs from 6 months of age as three primary doses administered 3 weeks apart with an annual booster. Vaccinated dogs will seroconvert, but the product datasheet describes a discriminatory serological test. Evidence for a cell-mediated immune response is also suggested. The vaccine claims to reduce the likelihood of infection and reduce the severity of clinical signs in infected dogs, but makes no public health claim for an effect on human disease prevalence [EB2].

## Feline vaccination guidelines

## Vaccination of individual cats
The Basic Immunization Schedule Guidelines and recommendations for core (recommended), non-core (optional) and not recommended vaccines for cats visiting the general veterinary practice are given in [fig_ref] Table 3: WSAVA Feline Vaccination Guidelines Core [/fig_ref]. The core vaccines for the cat are those that protect against feline panleukopenia (FPV), FHV-1 and FCV. A particular example of a vaccine that may be considered core in only some countries is that against rabies virus. In a geographical area in which this infection is endemic, the VGG recommends that all cats should be routinely vaccinated for the protection of both the pet and human populations. In some countries, mandatory rabies vaccination is a legal requirement (although this does not always include cats) and rabies vaccination is also required for international pet travel.
In terms of feline core vaccines it is important to realize that the protection afforded by the FCV and FHV-1 vaccines will not match the immunity provided by FPV vaccines. Thus the feline core respiratory disease vaccines should not be expected to give the same robust protection, nor the duration of immunity, that is seen with canine core vaccines. FCV vaccines have been designed to produce cross-protective immunity against multiple strains of FCV; however, it is still possible for infection and disease to occur in vaccinated adult animals [bib_ref] An isolated epizootic of hemorrhagic-like fever in cats caused by a novel..., Pedersen [/bib_ref] [bib_ref] An epizootic of highly virulent feline calicivirus disease in a hospital setting..., Schorr-Evans [/bib_ref] [EB1]. There is no FHV-1 vaccine that can protect against infection with virulent virus and infection may lead to the virulent virus becoming latent with the possibility of reactivation during periods of severe stress [bib_ref] Clinical, virological, and immunological parameters associated with superinfection of latently with FeHV-1..., Richter [/bib_ref] [EB1]. The reactivated virus may cause clinical signs in the vaccinated animal or the virus can be shed to susceptible animals and cause disease in them. The VGG recommends triennial revaccination of low-risk cats for FHV-1 and FCV on the basis of a published study showing a minimum duration of partial, but clinically significant, immunity of 7.5 years for these core vaccines [bib_ref] Long-term immunity in cats vaccinated with an inactivated trivalent vaccine, Scott [/bib_ref]. A more recent study of a MLV FHV-1/FCV vaccine seemed to show much less substantial, partial protection against FHV-1 at 3 years post vaccination; although the FCV partial protection was comparable to that shown by Scott and Geissinger in1999 [bib_ref] Three-year duration of immunity for feline herpesvirus and calicivirus evaluated in a..., Jas [/bib_ref]. . The VGG recommends that annual revaccination of cats against FHV-1/FCV be carried out in higher-risk situations. A low-risk cat might be defined as a solitary, indoor animal that does not visit a boarding cattery. A higher-risk cat might be defined as an animal that regularly visits a boarding cattery or that lives in a multicat, indoor-outdoor household. Moreover, the VGG encourages practitioners to consider the timing of administration of FHV-1/FCV vaccines to higher-risk, regularly boarding cats. The most robust immunity conferred by these vaccines occurs within the 3-month period after vaccination [bib_ref] Feline herpesvirus, Gaskell [/bib_ref] [EB1], and so administration of these vaccines might best be timed for immediately before a regularly boarded cat is due to make an annual visit to the cattery.
Vaccination against feline leukaemia virus (FeLV) is also often a point of debate amongst experts. The VGG regards FeLV as a noncore vaccine [fig_ref] Table 3: WSAVA Feline Vaccination Guidelines Core [/fig_ref] , but fully appreciates that use of this product must be determined by the lifestyle and perceived exposure risk of individual cats and the prevalence of infection in the local environment. Many feline experts believe that even though the prevalence of FeLV infection is now markedly reduced in many parts of the world due to successful control programmes [bib_ref] The presence of leukaemia (lymphosarcoma) and feline leukaemia virus (FeLV) in cats..., Weijer [/bib_ref] [bib_ref] Control of feline leukaemia virus infection by a removal programme, Weijer [/bib_ref] [bib_ref] Changes in prevalence of progressive feline leukaemia virus infection in cats with..., Meichner [/bib_ref] [EB1], in geographical areas in which FeLV infection remains prevalent, any cat less than 1 year old with an element of outdoor lifestyle (e.g. even living with a cat that goes outdoors) should receive the benefit of protection by routine vaccination with two doses of vaccine given 2-4 weeks apart starting not earlier than 8 weeks of age. This 'risk-benefit' analysis for FeLV should form a routine part of the feline vaccination interview and only FeLV-negative cats should be vaccinated.
The VGG has also reconsidered the FIV vaccine, which in previous iterations of these guidelines has been categorized as 'not recommended'. The basis for this categorization was: (1) questions over the cross-protection between subtypes of virus included in the vaccine and those subtypes and recombinants in the field in different geographical areas [bib_ref] Protection against homologous but not heterologous challenge induced by inactivated feline immunodeficiency..., Hosie [/bib_ref] [bib_ref] Limited efficacy of an inactivated feline immunodeficiency virus vaccine, Dunham [/bib_ref] [bib_ref] Feline immunodeficiency virus pathogenesis and development of a dual-subtype feline-immunodeficiency-virus vaccine, Yamamoto [/bib_ref] [bib_ref] Feline immunodeficiency virus (FIV) vaccine efficacy and FIV neutralizing antibodies, Coleman [/bib_ref] [bib_ref] Neutralising antibody response in domestic cats immunised with a commercial feline immunodeficiency..., Beczkowski [/bib_ref] [EB1], (2) the interference of the vaccine with antibody testing used for diagnosis of FIV infection [bib_ref] Vaccine protection against feline immunodeficiency virus: setting the challenge, Hosie [/bib_ref] [EB1], and (3) the fact that this is an adjuvanted vaccine that must be given repeatedly (a primary course of three injections and annual revaccination) to a species susceptible to injection site sarcoma. The VGG is aware that in some parts of the world, there remains a significant prevalence of FIV seropositivity and/or infection [bib_ref] Prevalence of antibody to feline immunodeficiency virus in some cat populations, Bennett [/bib_ref] [bib_ref] Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus in..., Hosie [/bib_ref] [bib_ref] Feline immunodeficiency virus: prevalence, disease associations and isolation, Friend [/bib_ref] [bib_ref] Prevalence of feline immunodeficiency virus and feline leukemia virus infections in random-source..., Glennon [/bib_ref] [bib_ref] Prevalence of feline immunodeficiency virus and other retroviral infections in sick cats..., Bandecchi [/bib_ref] [bib_ref] Prevalence of feline immunodeficiency virus in submissions of feline serum to a..., Hitt [/bib_ref] [bib_ref] Prevalence of feline leukemia virus and antibodies to feline immunodeficiency virus in..., Ueland [/bib_ref] [bib_ref] The prevalence of feline immunodeficiency virus infection in hyperthyroid cats, Jones [/bib_ref] [bib_ref] Prevalence of antibodies to feline parvovirus, calicivirus, herpesvirus, coronavirus, and immunodeficiency virus..., Hofmann-Lehmann [/bib_ref] [bib_ref] Prevalence of FIV and FeLV infections in cats in Istanbul, Yilmaz [/bib_ref] [bib_ref] Prevalence of feline leukemia virus infection and serum antibodies against feline immunodeficiency..., Lee [/bib_ref] [bib_ref] Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus and..., Muirden [/bib_ref] [bib_ref] Prevalence of feline immunodeficiency virus infection in domesticated and feral cats in..., Norris [/bib_ref] [bib_ref] Prevalence of feline immunodeficiency virus and feline leukaemia virus among client-owned cats..., Gleich [/bib_ref] [bib_ref] Naturally acquired feline immunodeficiency virus (FIV) infection in cats from western Canada:..., Ravi [/bib_ref] [bib_ref] Prevalence and risk factors of feline leukaemia virus and feline immunodeficiency virus..., Bande [/bib_ref] [bib_ref] A door-to-door prevalence study of feline immunodeficiency virus in Australia, Fung Martel [/bib_ref] [bib_ref] Prevalence of viral infections in cats in southwestern Poland in the years, Rypula [/bib_ref] [EB1]. There are now discriminatory serological tests [bib_ref] Serological differentiation of FIV-infected cats from dual-subtype feline immunodeficiency virus vaccine (Fel-O-Vax..., Kusuhara [/bib_ref] [bib_ref] Differentiation of feline immunodeficiency virus vaccination, infection, or vaccination and infection in..., Levy [/bib_ref] [bib_ref] Determining the feline immunodeficiency virus (FIV) status of FIV-vaccinated cats using point-of-care..., Westman [/bib_ref] and more robust polymerase chain reaction (PCR) testing for the diagnosis of FIV infection [bib_ref] Evaluation of a novel nested PCR for the routine diagnosis of feline..., Arjona [/bib_ref] [bib_ref] Dual-emission fluorescence resonance energy transfer (FRET) real-time PCR differentiates feline immunodeficiency virus..., Wang [/bib_ref] [bib_ref] Validation of real-time polymerase chain reaction tests for diagnosing feline immunodeficiency virus..., Morton [/bib_ref] [EB1]. In many countries, it is most unlikely that cat owners will be persuaded to keep their cats indoors, away from the major risk of FIV transmission (bites by infected cats). Disease progression in FIV-infected cats has recently been shown to be impacted by housing conditions and number of cats in the household [bib_ref] Contrasting clinical outcomes in two cohorts of cats naturally infected with feline..., Beczkowski [/bib_ref]. Given that this vaccine has been shown to have efficacy in some studies, but not in others, and might benefit some at-risk populations of cats, the VGG has reclassified the product as a non-core vaccine. Kitten Vaccination and the 6-or 12-Month Booster As discussed for puppies, most kittens are protected by MDA in the first weeks of life. However, without serological testing, the level of protection and the point at which the kitten will become susceptible to infection and can respond immunologically to vaccination are unknown. This is related to the level of maternal antibody and variation in uptake of MDA between litters and individuals. In general, MDA will have waned by 8-12 weeks of age to a level that allows an active immunological response; however, kittens with poor MDA may be vulnerable (and capable of responding to vaccination) at an earlier age, while others may possess MDA at such high titres that they are incapable of responding to vaccination until sometime after 12 weeks of age. The VGG has reviewed recent studies suggesting that up to one third of kittens may fail to respond to a final core vaccine given at 16 weeks of age and that a proportion of kittens may still have blocking MDA at 20 weeks of age [bib_ref] Prevalence of serum antibody titers against feline panleukopenia virus, feline herpesvirus 1,..., Digangi [/bib_ref] [bib_ref] Vaccination against feline panleukopenia: implications from a field study in kittens, Jakel [/bib_ref]. The VGG notes that one of these studies was of a relatively low number of animals, dominated by one breed, within a cattery setting, and suggests that the data may not be fully applicable to the wider feline population. Nevertheless, the VGG has increased the recommended age for the final vaccination in the series of primary core vaccinations from 14-16 weeks of age to 16 weeks or older .
The VGG recommendation for the core vaccination of kittens is therefore in line with the schedules proposed for puppies above: beginning at 6-8 weeks of age and then repeating vaccination every 2-4 weeks until 16 weeks of age or older. Therefore the number of kitten primary core vaccinations will be determined by the age at which vaccination is started and the chosen revaccination interval. Possible schedules are outlined in [fig_ref] Table 5: weeks, 13 weeks, 17 weeks then 26 or 52 weeks [/fig_ref]. By this recommendation, when vaccination is started at 6 or 7 weeks of age, a course of four primary core vaccines would be administered, but only three would be required with an 8-or 9-week start.
An integral part of core vaccination of kittens is the 'booster' vaccine that has traditionally been given either at 12 months of age or 12 months after the last of the primary series of kitten vaccines. The main aim of this vaccine is to ensure that a protective immune response develops in any cat that may have failed to respond to any of the three vaccines in the primary core series, rather than necessarily 'boosting' the immune response. The delivery of this vaccine at 12 months of age is likely to have been chosen historically as a convenient time to request the owner to attend the practice for a first annual health check. This therefore implies that should an individual kitten fail to respond to any of the three primary core vaccinations, that kitten may be unprotected until it receives this 12-month vaccine. This might account for occurrences of infectious disease in a proportion of vaccinated kittens at less than 12 months of age. The VGG has re-evaluated this practice and now suggests that veterinarians might wish to reduce this possible window of susceptibility by bringing forward this vaccine from 52 weeks to 26 weeks of age (or indeed at any time point between 26 and 52 weeks of age; however, 26 weeks of age provides a convenient timing). This practice will require that pet owners clearly understand why this is recommended, because as indicated in [fig_ref] Table 5: weeks, 13 weeks, 17 weeks then 26 or 52 weeks [/fig_ref] , adopting such a protocol will mean that vaccination started in a 6 or 7 week old kitten, might now entail up to five vaccine visits in the first 6 months of life. For core vaccines, after a 26 week 'booster', another core vaccine would not be required for at least another 3 years (for a low-risk cat). As for puppies, adoption of the 26 week vaccination approach would not preclude a first annual health check at 12 or 16 months of age.

## Revaccination of adult cats
Cats that have responded to vaccination with MLV core vaccines maintain a solid immunity (immunological memory) against FPV for many years in the absence of any repeat vaccination. Immunity against FCV and FHV-1 is only partial . The VGG recommendation for adult 'low-risk' cats is for revaccination with MLV core vaccines at intervals of 3 years or longer. For 'higher-risk' cats (see definitions above) the veterinarian might consider administering FPV vaccine no more frequently than every 3 years, but giving FCV and FHV-1 vaccines annually, with these latter products timed for administration shortly before any regular annual visit to a boarding cattery [EB1]. These recommendations do not generally apply to killed core vaccines (except for rabies) nor to the non-core vaccines, and particularly not to vaccines containing bacterial antigens. Thus Chlamydia (formerly Chlamydophila; [bib_ref] Emendation of the family Chlamydiaceae: proposal of a single genus, Chlamydia to..., Sachse [/bib_ref] and Bordetella products, if their use is deemed necessary, require annual boosters for the limited protection afforded by these products .
Therefore, according to these guidelines, an adult cat may still receive an annual vaccination; however, the components of that vaccination may differ from year to year. Typically, core vaccines (especially FPV) are currently administered triennially with respiratory virus vaccines given according to risk and chosen non-core products being given annually. The VGG is aware that in some countries only multi-component products containing core and non-core combinations are available. The VGG would encourage manufacturers to make a full range of vaccines available wherever possible or, at the very least, make a core-only combination for those not wanting to give any of the non-core vaccines.
An adult cat that received a complete course of vaccination for FPV, FHV-1 and FCV as a kitten (including the 6-or 12-month booster), but may not have been regularly vaccinated as an adult requires only a single dose of MLV core vaccine to boost immunity . An adopted adult cat (or kitten over 16 weeks of age) of unknown vaccination history requires only a single dose of MLV FPV core vaccine to engender a protective immune response to that virus. In contrast, an adopted adult cat of unknown vaccination history should receive two doses of MLV FHV-1/FCV vaccine (2-4 weeks apart) to establish an adequate immune response [EB2].

## Sites of vaccination for cats
Vaccines (of any type) are one class of injectable product that has been linked to the pathogenesis of the feline injection site sarcoma (FISS) and particular attention has focused on the administration of adjuvanted FeLV and rabies vaccines [bib_ref] Epidemiologic evidence for a causal relation between vaccination and fibrosarcoma tumorigenesis in..., Kass [/bib_ref]. FISS has been the subject of much research and there are a number of recent reviews on the subject [bib_ref] Feline injection-site sarcoma: past, present and future perspectives, Martano [/bib_ref] [bib_ref] Comparative vaccine-specific and other injectable-specific risks of injection-site sarcomas in cats, Srivastav [/bib_ref] [bib_ref] Injection site-associated sarcoma in the cat: treatment recommendations and results to date, Ladlow [/bib_ref]. Although the pathogenesis of FISS remains unproven, current belief is that a localized chronic inflammatory reaction initiates malignant transformation of mesenchymal cells and that this process has some genetic basis. Most subcutaneous injections (including of vaccines) have traditionally been given into the interscapular region of the cat, which remains a common site for formation of a FISS. The infiltrative nature of these tumours means that radical surgical resection is often necessary to attempt removal of these lesions although adjunctive treatment modalities are also used [bib_ref] Feline injection-site sarcoma: past, present and future perspectives, Martano [/bib_ref] [bib_ref] Injection site-associated sarcoma in the cat: treatment recommendations and results to date, Ladlow [/bib_ref].
In North America the response to this issue was the recommendation of a protocol whereby the two perceived high-risk adjuvanted vaccines would be administered into distinct anatomical sites that would be more amenable to surgical removal of any FISS that might develop. Accordingly the recommendation 'left leg leukaemia, right leg rabies' suggested that FeLV vaccine should be given as far distal as possible into the left hindlimb, whilst rabies vaccine should be given as far distal as possible into the right hindlimb. This recommendation remains in the current AAFP guidelines [bib_ref] AAFP Feline Vaccination Advisory Panel report, Scherk [/bib_ref] , which also specify administration of the three feline core vaccines into a distal forelimb. One study evaluated the effect of this practice by comparing the anatomical distribution of FISS in cats before the recommendation was made and after the practice was adopted [bib_ref] Temporal changes in characteristics of injection-site sarcomas in cats: 392 cases (1990-2006), Shaw [/bib_ref]. The data showed a significant decrease in the prevalence of interscapular FISS and an increase in prevalence of tumours in the right (but not left) forelimb. More notably, there was also an increase in the number of tumours reported arising in the combined regions of the right hindlimb with right lateral aspect of the abdomen (12.5% to 25.0%) and the left hindlimb with left lateral aspect of the abdomen (11.4% to 13.8%). This was attributed to the difficultly of injecting into the distal hindlimb and these abdominal sites being accidentally injected. This practice has not been widely adopted outside of North America.
Recently, one publication has shown the efficacy of administering FPV and rabies vaccines into the tail of cats [bib_ref] Tail vaccination in cats: a pilot study, Hendricks [/bib_ref]. Adult cats from a community trap-neuter-return programme were given trivalent MLV core vaccine (FPV, FHV-1, FCV) into the distal third of the dorsal tail with inactivated rabies vaccine administered 2 cm distal to the site of the trivalent vaccination. Seroconversion occurred in all cats to FPV and all but one cat for rabies virus. Tail vaccination was reported to be well tolerated by the cats in this small study. In the 2010 WSAVA vaccination guidelines, the VGG proposed the alternative of delivering vaccine into the skin of the lateral thorax, or better, the lateral abdomen [bib_ref] Guidelines for the vaccination of dogs and cats, Day [/bib_ref]. Tail injection may prove to be a safer alternative than distal limb injections or lateral body wall injections, but further studies of tail vaccination will be required.
This remains a confusing and contentious area and individual practitioners must decide for themselves which approach is practical for their own practice setting. However, the following principles should still be applied:
- Any risk of FISS is outweighed by the benefit of protective immunity conferred by vaccines. Current estimates of the prevalence of FISS are 1 in every 5,000 to 12,500 cats vaccinated [bib_ref] World Wide Web-based survey of vaccination practices, postvaccinal reactions, and vaccine site-associated..., Gobar [/bib_ref]. - Non-adjuvanted vaccines should be administered to cats wherever possible. - Vaccines (particularly adjuvanted products) or other injectables should not be administered into the interscapular region. - Vaccines (particularly adjuvanted products) should be administered into other subcutaneous (and not intramuscular) sites. The choice of these sites should be based on a balance between the ease of surgical resection of any FISS that might develop and acceptable safety for the vaccinator (i.e. to avoid accidental self-injection during difficult restraint of the animal). - Vaccines should be administered into a different site on each occasion. This site should be recorded in the patient's record or on the vaccination card by use of a diagram indicating which products were administered on any one occasion. The sites should be 'rotated' on each occasion. Alternatively, a practice might develop a group policy that all feline vaccinations are administered to a specific site during one calendar year and this site is then rotated during the following year. - The VGG encourages all cases of suspected FISS to be notified via the appropriate national reporting route for suspected adverse reactions or to the vaccine manufacturer.

## Serological testing
Since the publication of the 2010 guidelines, one commercial in-practice rapid test for determination of serum antibody to FPV, FCV and FHV-1 has become available. This test has now been validated and applied in a series of published investigations [bib_ref] Evaluation of an in-house dot enzyme-linked immunosorbent assay to detect antibodies against..., Mende [/bib_ref]. This test kit may be used for the determination of the presence of protective antibody against FPV as there is excellent correlation between the presence of such antibody and resistance to infection [bib_ref] Use of serologic tests to predict resistance to feline herpesvirus 1, feline..., Lappin [/bib_ref] [EB1]. The FPV test kit is reported to have 89% specificity and 79% sensitivity [bib_ref] Evaluation of an in-house dot enzyme-linked immunosorbent assay to detect antibodies against..., Mende [/bib_ref] The correlation between circulating serum antibody and protection against FCV and FHV-1 infection is less robust than the presence of adequate local mucosal immunity and cell-mediated immunity, respectively. For that reason, a negative test result for FCV or FHV-1 antibody would not necessarily indicate lack of protection in a particular cat [bib_ref] Use of serologic tests to predict resistance to feline herpesvirus 1, feline..., Lappin [/bib_ref] [EB1]. These tests can be applied in practice as described above for the dog: for determination of protection of kittens following FPV vaccination, for determination of protection against FPV in adult cats (in order to inform decisions about revaccination) and for use in the shelter situation in the control of outbreaks of FPV infection. It should be emphasized that antibody testing for FIV is used to diagnose disease and is of no value in determining immunity to FIV, but as discussed above, where FIV vaccine is used and FIV infection is suspected, diagnosis should be made using a discriminatory serological test or, preferably, a validated PCR test.

## Vaccination of dogs and cats in the shelter environment
An animal shelter is a holding facility for animals usually awaiting adoption, rescue or reclamation by owners. In general, animal shelters are characterized by a random source population with a mostly unknown vaccination history, high population turnover and high infectious disease risk. The term 'shelter' encompasses situations ranging from sanctuaries that possess a stable population, to facilities that admit hundreds of animals per day, to rescue and foster homes that care for multiple individuals or litters at any given time. Just as vaccination strategy varies with each individual pet, there is no one-size-fits-all strategy for vaccinating shelter animals. The likelihood of exposure and the potentially devastating consequences of infection necessitate a clearly defined shelter vaccination program.
Shelter medicine differs from individual care in that clinicians have to practice in an environment where eradication of infectious disease cannot be attained. It is possible, however, to minimize the spread of infections within a high-density, high-risk population and maintain the health of not-yet-infected individuals. When the overall purpose is to place healthy pets into welcoming homes, the time and effort dedicated to controlling infectious disease is only one of many variables in the complex shelter medicine and husbandry equation. The recommendations provided here attempt to address some shelter-unique issues as they pertain to vaccination and disease control.
Guidelines and recommendations for vaccines to be used in shelters are given in Tables 2 and 4. In these updated guidelines, we have standardized the recommendations for puppies and kittens entering a shelter to indicate that core vaccination may be started as early as 4-6 weeks of age, and (where funding permits) revaccination should be every 2 weeks until the animal reaches 20 weeks of age, if it remains in the shelter until that time . Recent US studies have shown that cats entering shelters may be seropositive for vaccine-preventable infectious disease agents. [bib_ref] Prevalence of serum antibody titers against feline panleukopenia virus, feline herpesvirus 1,..., Digangi [/bib_ref] reported seropositivity for FPV (60.2%), FHV-1 (89%) and FCV (63.4%) and [bib_ref] Response of feral cats to vaccination at the time of neutering, Fischer [/bib_ref] reported seropositivity for FPV (33%), FHV-1 (21%), FCV (64%) and rabies virus (3%). Seropositivity to CDV (41.2%) was less than for CPV (84.3%) in dogs entering one US shelter [bib_ref] Prevalence of positive antibody test results for canine parvovirus (CPV) and canine..., Litster [/bib_ref] and in another study 35.5% of dogs were seropositive to both CDV and CPV, 7.7% to CDV only, 31.5% to CPV only and 25.3% to neither virus [bib_ref] Prevalence of protective antibody titers for canine distemper virus and canine parvovirus..., Lechner [/bib_ref]. If unambiguous documentation of vaccination is provided for an adult animal at the time of admission to a shelter, there is no reason to revaccinate with canine core vaccines, but feline core vaccines, specifically FCV and FHV-1, may be of value in boosting immunity.
The VGG discriminates between a shelter and a boarding kennel/cattery. The latter are facilities where fully vaccinated animals may be temporarily boarded for relatively short periods of time (e.g. when owners are on vacation). It should be a requirement of entry to any such facility that the individual dog or cat is fully vaccinated with core products given according to the guidelines presented herein. In dogs, the use of non-core vaccines against respiratory infections is also appropriate under these circumstances. The VGG is aware that in some countries vaccination protocols for animals entering a boarding kennel/cattery are formulated by local authorities and may be contrary to current guidelines (e.g. insistence on annual revaccination). The VGG encourages such authorities to reconsider these recommendations in light of current scientific thinking and product availability and encourages the veterinary profession and national associations to lobby for such change.
Since publication of the 2010 guidelines, the availability of rapid in-house serological test kits has had major impact on the management of outbreaks of CDV, CPV or FPV in animal shelters . The approach to use of these kits in such situations is outlined in [fig_ref] Table 7: Use of Serological Testing in a Shelter Infectious Disease Outbreak [/fig_ref].

## General considerations comprehensive individual care beyond vaccination
In the past, veterinary practice has benefited from the annual administration of vaccines. By encouraging owners to bring their pets yearly for vaccination, veterinarians were able to recognize and treat disease earlier than might otherwise have been the case. In addition, the annual visit provided an opportunity to inform clients of important aspects of canine and feline health care.
Unfortunately, many clients have come to believe that vaccination is the most important reason for annual veterinary visits. Veterinarians have been concerned that a reduction in vaccination frequency will cause clients to forgo the annual visits and that the E16 Journal of Small Animal Practice - Vol 57 - January 2016 -  2016 WSAVA quality of care will diminish. It is therefore essential that veterinarians stress the importance of all aspects of a comprehensive individualized health care program. Emphasis should be placed on detailed history taking; thorough physical examination performed in the presence of the client, and individualized patient care. The importance of dental care, proper nutrition, appropriate diagnostic testing and the control of parasites and of zoonotic diseases should be addressed during evaluation of each pet. Behavioural concerns should be discussed, as well as the necessity for more frequent, tailored examination of young and geriatric animals and animals of particular breeds with well characterized disease predispositions. Discussion of vaccination is simply one part of the annual health check visit.
During regular (usually annual) health checks, clinicians should assess the need for core and non-core vaccines for that particular year. The practitioner should explain to the client the types of vaccines available, their potential benefits and risks, and their applicability to the particular animal, given its lifestyle and risk of exposure. While an animal might not receive core vaccination every year, most non-core vaccines require annual administration -so owners will continue to see their animal vaccinated annually. The regional incidence and risk factors for various infectious diseases should also be discussed. Ways to reduce the impact of acquired disease (e.g. avoiding overcrowding, improving nutrition, and restricting access to infected animals) should also be reviewed.
Vaccinations should be considered as only one component of a comprehensive preventive health care plan individualized based on the age, breed, health status, environment (potential exposure to harmful agents), lifestyle (contact with other animals) and travel habits of the pet.
Age has a significant effect on the preventive health care needs of any given individual. Puppy/kitten programs have traditionally focused on vaccinations, parasite control and neutering. Today, opportunity exists to incorporate behaviour counselling and zoonotic disease management. For the ageing pet, senior care programs are becoming increasingly popular. Nutritional, dental disease and parasite control assessment and counselling should take place on an individualized basis throughout the life of the pet. There is no evidence that older dogs and cats, which have been fully vaccinated as pups or kittens, require a specialized programme of core vaccination [bib_ref] Guidelines for the vaccination of dogs and cats, Day [/bib_ref] [bib_ref] Vaccination protocols for companion animals: the veterinarian's perspective, Horzinek [/bib_ref]. Experimental evidence shows that older dogs and cats have persisting immunological memory to core vaccines, as detected by measurement of serum antibody, and that this may be readily boosted by administration of a single vaccine dose [bib_ref] Guidelines for the vaccination of dogs and cats, Day [/bib_ref] [EB1]. In adult animals, decisions about revaccination with most core products (CDV, CAV and CPV and FPV) may be made via serological testing. Practitioners who offer this alternative to vaccination report that it is greatly appreciated by owners who may have concerns about vaccination frequency and offering this alternative acts as a 'practice builder'. By contrast, aged animals may not be as efficient at mounting primary immune responses to novel antigens that they have not previously encountered [bib_ref] Guidelines for the vaccination of dogs and cats, Day [/bib_ref] [EB1]. Studies of UK dogs and cats vaccinated for the first time against rabies for pet travel have clearly shown that more aged animals fail to achieve the legally required antibody titre [bib_ref] Factors influencing the antibody response of dogs vaccinated against rabies, Kennedy [/bib_ref] [EB1].
The environment in which a pet resides can profoundly affect its health status and should be assessed during annual health care visits in order to define risk factors and develop appropriate preventive measures.
By estimating the extent to which dogs and cats come into contact with other animals in unobserved circumstances, veterinarians can assess the need for non-core vaccinations. Dogs that visit kennels, grooming salons, common areas and wooded, tick-infested areas are potentially at greater risk from certain infectious diseases than dogs that do not frequent these areas.
Just as the human population has become more mobile, so has the pet population, resulting in potential exposure to infectious agents, parasites and environmental hazards not found where the animal normally lives. Determining past and anticipated future travel during each visit allows for greater individualization of preventive care and diagnostic testing plans.

## Medical record documentation
At the time of vaccine administration, the following information should be recorded in the patient's permanent medical record:
- date of vaccine administration - identity (name, initials or code) of the person administering the vaccine - vaccine name, lot or serial number, expiry date and manufacturer - site and route of vaccine administration.
The use of peel-off vaccine labels and stamps that imprint the medical record with the outline of a pet facilitates this type of record keeping which is mandatory in some countries. Adverse events should be recorded in a manner that will alert all staff members during future visits. Informed consent should be documented in the medical record in order to demonstrate that relevant information was provided to the client and that the client authorized the procedure (e.g. 'off-label' use of products as discussed above). At the very least, this notation should indicate that a discussion of risks and benefits took place prior to vaccination.
VGG recommends that vaccination certificates be designed to include not just the dates on which vaccines were administered, but also a field for the veterinarian to state the date on which vaccination is next recommended. This will help diminish confusion in the minds of pet owners and kennel/cattery proprietors. Annually or more often in very high-risk animals not protected by annual booster. Non-core. B. bronchiseptica is available as a single product or in combination with CPiV or with both CPiV and CAV2. Transient (3-10 days) coughing, sneezing, or nasal discharge may occur in a small percentage of vaccinates. Intranasal or oral vaccines MUST NOT be delivered by parenteral injection as this may lead to severe adverse reactions, including death.
Bordetella bronchiseptica (killed bacterin, parenteral Bordetella bronchiseptica (cell wall antigen extract, parenteral)
Administer one dose at 6-8 weeks and one dose at 10-12 weeks of age. Two doses 2-4 weeks apart.
Annually or more often in very high-risk animals not protected by annual booster. Non-core. Intranasal or oral products are preferred to the killed parenteral to provide local protection [EB4]; however, a review published at the time of compilation questions this advantage [bib_ref] How well do vaccines for Bordetella bronchiseptica work in dogs? A critical..., Ellis [/bib_ref] In Australia there is a monovalent vaccine containing serogroup australis and in New Zealand monovalent serogroup icterohaemorrhagiae vaccines are available.
Initial dose at 8 weeks of age or older. A second dose is given 2-4 weeks later. Two doses 2-4 weeks apart.
Annually. Non-core. Leptospira vaccines have been developed to account for the known circulating pathogenic serogroups in different geographical areas. Note that Leptospira serogroups may include multiple serovars. There is often confusion with the use of the terms 'serogroup' and 'serovar'. Vaccination should be restricted to use in geographical areas where a risk of exposure has been established or for dogs whose lifestyle places them at risk. This vaccine is known to provide protection that is less robust and may be of shorter duration, and therefore these products must be administered annually [EB1].
In the past, Leptospira bacterin vaccines have been suggested to be linked to a higher prevalence of allergic adverse events -particularly in small breed dogs. Administer one dose at time of admission (from 6-8 weeks of age) and a second dose 2 weeks later.
Two doses 2 weeks apart are recommended. Parenteral vaccination is recommended only when it is not possible to administer an intranasal or oral vaccine. Canine respiratory disease complex ('kennel cough') is not a vaccine-preventable disease and the vaccine should only be used to help manage the disease.

## Rabies
A single dose should be administered at the time of discharge from the facility.
A single dose should be administered at the time of discharge from the facility. The administration of rabies vaccine will be determined by whether the shelter is in a country in which the disease is endemic, and by local statute.
In the USA, the CIV vaccine is often used in the shelter situation when two doses can be given 2 weeks apart. Many of the recommendations for shelters are different for use of the same vaccines for owned pet dogs in the practice situation. These recommendations take into account the potential for high infectious disease pressure in the shelter environment.

## E20
Journal of Small Animal Practice - Vol 57 - January 2016 -  2016 WSAVA MLV preparations are preferable. Use of intranasal FPV vaccines is not recommended in the shelter environment [bib_ref] A commentary on parvovirus vaccination, Schultz [/bib_ref]. Use of intranasal FCV/FHV-1 MLV vaccines may be preferable when rapid onset (48 hrs) of immunity is important. Post-vaccinal sneezing, more commonly seen following administration of intranasal FCV/FHV-1 vaccine is impossible to distinguish from active infection.

## Rabies
A single dose should be administered at the time of discharge from the facility.
A single dose should be administered at the time of discharge from the facility.
The administration of rabies vaccine will be determined by whether the shelter is in a country in which the disease is endemic and vaccination is required by law.
The VGG does not recommend the use of other feline vaccines in the shelter situation. provides examples of possible vaccination schedules for puppies and kittens where vaccines are given either every 3 or 4 weeks, as would normally be done in veterinary practice for owned pet animals. Although revaccination every 2 weeks might be used in areas of high infectious disease pressure in some geographical areas, such a protocol is not shown for simplicity of presentation. After the 26 or 52 week booster vaccine; vaccinate with core products no more frequently than every 3 years (with the exception of feline respiratory virus vaccines for higher risk cats).

## Table 6. vaccine husbandry: key points for veterinary practitioners
- Vaccines have an optimum storage temperature that is usually between 2-8C (domestic refrigerators should be maintained at 4C). These products should not be frozen or positioned adjacent to the freezer compartment of the refrigerator, and refrigerator temperature should be monitored regularly.
Vaccines transported into the field should also be subject to continuation of the 'cold chain'.
- Freeze-dried vaccines should be reconstituted immediately before use with appropriate diluent or liquid vaccine given simultaneously (as per manufacturer's recommendations). It is bad practice and contraindicated to make up the vaccines anticipated to be used during the day first thing in the morning. Some vaccine components (e.g. CDV, FHV-1) are particularly labile in this regard and so these vaccines may not induce adequate immunity if not reconstituted just before use.
- Vaccines should only be mixed together in the same syringe if this is specified as acceptable in the manufacturer's data sheets.
- Syringes and needles for vaccines should not be re-utilized.
- Vaccine injection sites should not be sterilized with alcohol or other disinfectant as this may inactivate infectious (MLV) vaccines.
- Vaccines should be 'in date' and precise details of batch numbers, components and site of injection should be noted in the animal's medical record.
[From]. Seropositive animals These are protected and will not become infected or die. These should be separated from the non-or low-responder animals.
Seronegative animals These should be separated from the seropositive animals. These animals are susceptible and should not be adopted out of the shelter until after the incubation period for the infection (i.e. at least 2 weeks for CPV, at least 6 weeks for CDV). These animals should be vaccinated and retested to confirm seropositivity after the incubation periods above.
Animals outside of a shelter needing to be admitted in the face of a disease outbreak in the shelter Seropositive animals These may safely enter the shelter as they are protected from disease.

## Seronegative animals
These animals should be vaccinated and sent to foster homes until after they have seroconverted. They should not be allowed to enter the shelter until they are seropositive.

## Adverse events
Adverse events are defined as any side effects or unintended consequences (including lack of protection) associated with the administration of a vaccine product. They include any injury, toxicity or hypersensitivity reaction associated with vaccination, whether or not the event can be directly attributed to the vaccine. Adverse events should be reported, whether their association with vaccination is recognized or only suspected. A vaccine adverse event report should identify the product(s) and animal(s) involved in the event(s) and the individual submitting the report. Reporting field observations of unexpected vaccine performance is the most important means by which the manufacturer and the regulatory agency are alerted to potential vaccine safety or efficacy problems that may warrant further investigation. The purpose of pre-licensure safety studies is to detect relatively common adverse events. Rare or delayed adverse events will be detected only by postmarketing surveillance through analysis of reported adverse events. Adverse events should be reported to the manufacturer and/or the local regulatory authority. In many countries governmental surveillance schemes are not available and reactions should therefore be notified to the manufacturer. The VGG recognizes that there is gross under-reporting of vaccine-associated adverse events, because of the passive nature of reporting schemes, which impedes knowledge of the ongoing safety of these products . The VGG would actively encourage all veterinarians to participate in such surveillance schemes.
If a particular adverse event is well documented, reporting serves to provide a baseline against which future reports can be compared. In addition, reported adverse events can lead to detection of previously unrecognized reactions, detection of increases in known reactions, recognition of risk factors associated with reactions, identification of vaccine lots with unusual events or higher numbers of adverse events, and can further stimulate clinical, epidemiological or laboratory studies. Therefore, veterinarians are encouraged to report any clinically significant adverse event occurring during or after administration of any licensed vaccine. Reporting a vaccine adverse event is not an indictment against a particular vaccine; it facilitates review of temporally associated conditions and adds to the safety database of the product.

# Acknowledgments
The work of the Vaccination Guidelines Group has been generously sponsored by MSD Animal Health and the WSAVA. The VGG is an independent group of academic experts who have formulated these guidelines without consultation with industry. Representatives of the sponsoring company do not attend VGG meetings and the company does not have the right of veto over VGG recommendations.
The VGG again acknowledges the important work undertaken by the American Animal Hospital Association (AAHA) Canine Vaccine Task Force, the American Association of Feline Practitioners (AAFP) Feline Vaccine Advisory Panel in developing recommendations for the vaccination of dogs and cats (respectively) in North America. The VGG also acknowledges the work of the European Advisory Board on Cat Diseases (ABCD) in formulating recommendations for feline vaccination from the European perspective. E27 APPENDICES FACT SHEET: CANINE PARVOVIRUS TYPE 2 (CPV-2) VACCINES Types of Vaccines Available Modified Live Virus (MLV) Vaccines: There are three contemporary variants of CPV-2, which are referred to as CPV-2a, CPV-2b and CPV-2c. The original CPV-2 variant is rarely isolated nowadays, although it is still present in some modified live vaccines and can be shed from vaccine recipients. The most recent variant to emerge is CPV-2c and this genotype is recognized in North and South America, Europe, Africa and Asia [bib_ref] Canine parvoviruses in New Zealand form a monophyletic group distinct from the..., Ohneiser [/bib_ref]. All genotypes are antigenically related; challenge studies have shown that vaccination of dogs with current CPV vaccines containing either CPV-2 or CPV-2b will provide protective immunity against all the other variants, including CPV-2c [bib_ref] Canine parvovirus type 2 vaccine protects against virulent challenge with type 2c..., Spibey [/bib_ref] [bib_ref] Canine parvovirus -a review of epidemiological and diagnostic aspects with emphasis on..., Decaro [/bib_ref]. Conversely, there is one report of an outbreak of CPV-2c infection in vaccinated adult dogs [bib_ref] Evidence for immunisation failure in vaccinated adult dogs infected with canine parvovirus..., Decaro [/bib_ref]. These dogs had been vaccinated at 42, 57 and 90 days of age and the adults had received annual boosters. Inactivated (Killed) Vaccines: Only a few killed CPV-2 vaccines are available; they are less effective and take much longer to induce an immune response when compared with the MLV vaccines [bib_ref] Dog response to inactivated canine parvovirus and feline panleukopenia virus vaccines, Pollock [/bib_ref]. They are not recommended for routine use. Killed vaccines may provide some benefit in wild and exotic species or pregnant bitches, where some MLV vaccines are not recommended. However, killed CPV-2 vaccines have not been tested for safety or efficacy in these situations.

## Mechanisms and duration of immunity (doi)
- DOI after natural infection/disease is thought to be life-long in the majority of dogs. - DOI after vaccination with MLV vaccines is 9 years or longer, based on challenge and serological studies ). - DOI after vaccination with killed vaccines is 3 years or longer. - MDA interferes with active immunization for varying periods of time in the puppy, depending on the titre of colostral antibody and the amount of antibody absorbed after birth, as well as the specific vaccine [bib_ref] Maternally derived immunity to canine parvovirus infection: transfer, decline, and interference with..., Pollock [/bib_ref]. - The 'window of susceptibility' is defined as the period of time during which a pup can be infected by field virus, but vaccines cannot immunize. For highly effective MLV vaccines (i.e. high titre, low passage) the 'window of susceptibility' is as short as 2 weeks or less, while for less effective MLV vaccines, the window of susceptibility is as long as 10-12 weeks [bib_ref] Immuonogenicity of a low-passage, high-titer modified live canine parvovirus vaccine in pups..., Hoare [/bib_ref]. - After completing the puppy series at 16 weeks or older and vaccinating again at 26 or 52 months of age, revaccination need not be done more often than every 3 years. - In the absence of MDA, MLV vaccines provide immunity as early as 3 days after vaccination.
- The presence of serum antibody, regardless of titre, in an actively immunized dog over the age of 20 weeks is correlated with protection.

## Precautions
- MLV vaccines should not be used in wildlife species.
- MLV vaccines should not be used in pregnant bitches unless specifically indicated.
- Puppies younger than 4-6 weeks of age should not be vaccinated with MLV products.

## Disease facts
- After infection, it takes 3-7 days for signs of disease to appear.
- CPV-2 faecal shedding rarely persists for >2 weeks.
- Dogs persistently infected for >4 weeks have not been reported and one can expect the animal to die or clear the virus in that period of time. - In the environment, the virus can remain infectious for 1 year or more. Therefore, all facilities where infected animals have been present must be considered infected. tory disease associated with CAV-2 infection. They are exceptionally effective and will not cause the adverse reaction commonly seen with CAV-1 vaccines known as allergic uveitis or 'blue eye' [bib_ref] The 'blue eye' phenomenon, Curtis [/bib_ref]. In addition to parenteral MLV CAV-2 vaccine preparations there are combination or monovalent products to protect against the canine infectious respiratory disease complex (CIRDC), which includes Bordetella bronchiseptica and canine parainfluenza virus (CPiV) and CAV-2. The intranasal product that contains CAV-2, CPiV and Bordetella can be used to decrease the severity of CIRDC, but should not be used as the only vaccine to prevent ICH; for this purpose, the parenteral MLV-CAV-2 should also be given. Inactivated (Killed) Vaccines: Inactivated (killed) CAV-1 and CAV-2 vaccines are sold in some countries, but they are not recommended when MLV products are available, as they are less effective.

## Mechanisms and duration of immunity (doi)
- DOI after naturally-acquired canine infectious hepatitis is thought to be life-long in the majority of dogs.
- DOI after vaccination with MLV vaccines is 9 years or longer in the majority of dogs, based on challenge and serological studies ). - DOI for protection from ICH with killed CAV-1 or CAV-2 vaccines is likely to be shorter than for MLV products. - MDA will block immunization after vaccination with the parenteral product and so the last dose should be given along with the other core viral vaccines (e.g. CDV, CPV-2) when the puppy is 16 weeks of age or older. - After completing the puppy series at 16 weeks or older and vaccinating again at 26 or 52 weeks of age, revaccination need not be done more often than every 3 years. - In the absence of MDA, MLV vaccines protect against ICH as early as 5 days after vaccination.
- The presence of serum antibody, regardless of titre, in an actively immunized dog over the age of 20 weeks is correlated with protection.

## Precautions
- Intranasal CAV-2 vaccine is intended as an aid in the prevention of upper respiratory disease caused by CAV-2 and is not intended to protect against CAV-1 infection.

## Disease facts
- CAV-1 is transmitted primarily through contaminated secretions/excretions such as saliva and urine.
- CAV-1 and CAV-2 are moderately stable, surviving for several days to weeks in the environment.
- After experimental infection with CAV-1, it takes 5 days or longer for signs of ICH to appear.
- The 'window of susceptibility' is defined as the period of time during which a puppy can be infected by field virus, but vaccines cannot immunize. Unlike CPV-2 vaccines, there generally is not a prolonged 'window' for CAV-2 vaccines (i.e. <2 weeks). - CAV-2 is transmitted primarily through the air. - CIRDC has complex pathogenesis involving stress, poor ventilation, dust, ammonia gas in unsanitary facilities and infections with Streptococcus spp., Bordetella bronchiseptica, Mycoplasma spp., CAV-2, CPiV, CIV, canine pneumovirus and canine respiratory coronavirus. - CAV-2 combined with other agents associated with CIRDC can cause respiratory disease in 3-4 days. - As a multifactorial disease CIRDC is not vaccine-preventable. The current vaccines only help in reducing disease severity.

## Fact sheet: canine distemper virus (cdv) vaccines

## Types of vaccines available modified live virus (mlv) vaccines:
These are the most common products. They generally contain the CDV strains Rockborn, Snyder Hill, Onderstepoort, Lederle or others at various titres. There are many pathotypes of CDV [bib_ref] Canine distemper virus strains circulating among North American dogs, Kapil [/bib_ref] [bib_ref] Phylogenetic evidence of a new canine distemper virus lineage among domestic dogs..., Espinal [/bib_ref] which can cause varying clinical signs in a wide variety of species. However, serological differences among the many isolates are insignificant, and vaccination with any one of the current vaccines should provide protective immunity against any pathotype. MLV vaccines must not be used in wildlife species unless there is specific evidence that shows them to be safe. Vectored Recombinant (rCDV) Vaccines: A canarypox virus recombinant product is available in the USA and a few other countries. A specific canarypox vectored recombinant product has also been used in wildlife and exotic species [bib_ref] Comparison of oral and intramuscular recombinant canine distemper vaccination in African wild..., Connolly [/bib_ref].

## Precautions
- The MLV preparations are attenuated (modified and safe) for use in the domestic dog, not for use in wild and exotic species. These vaccines are highly virulent (e.g. in the black-footed ferret and grey fox), causing disease and death [bib_ref] Fatal vaccine-induced canine distemper virus infection in black-footed ferrets, Carpenter [/bib_ref] [bib_ref] Vaccine-induced canine distemper virus in black-footed ferrets, Pearson [/bib_ref] [bib_ref] Vaccine-associated canine distemper infection in a litter of African hunting dogs (Lycaon..., Durchfeld [/bib_ref]. Vaccination of these species with MLV vaccines should not be performed unless there is evidence to support the safety of a specific product. - Puppies younger than 4-6 weeks of age should not be vaccinated with MLV vaccines.

## Disease facts
- Signs of disease appear between 2-6 weeks after infection. - During the incubation period, CDV causes immunosuppression, making the animal more susceptible to microbial infections. These secondary infections may lead to respiratory disease, pneumonia and death, before the more typical signs of distemper virus infection appear. - In the environment, the virus quickly loses infectivity.

## Fact sheet: feline parvovirus (fpv) vaccines

## Types of vaccines available
Modified Live Virus (MLV) Vaccines: These preparations contain attenuated (avirulent) feline parvovirus (feline panleukopenia virus) at various titres, without adjuvant. There are injectable preparations and others for intranasal application, in combination with other vaccinal antigens (e.g. FCV and FHV-1). MLV vaccines are advantageous for their faster onset of action, greater efficacy at overcoming maternal antibody and greater likelihood of conferring sufficient immunity [bib_ref] Feline panleukopenia virus, feline herpesvirus-1 and feline calicivirus antibody responses in seronegative..., Lappin [/bib_ref]. Intranasal FPV combination vaccines should not be used in the shelter environment or if used for FCV/FHV-1 immunity, they should be given simultaneously with an MLV-FPV parenteral product [bib_ref] A commentary on parvovirus vaccination, Schultz [/bib_ref]. Inactivated (Killed) Vaccines: Killed adjuvanted FPV vaccines are available; a single injected dose of some products may induce good antibody responses in naive cats within a relatively short time span. However, all killed FPV products require two doses 2-4 weeks apart and immunity is present only after the second dose. Killed vaccines may be beneficial in wild and exotic species, pregnant queens or retrovirally-infected cats, where MLV vaccines are not recommended.

## Mechanisms and duration of immunity (doi)
- DOI after natural infection/disease is life-long. - DOI after vaccination with MLV vaccines is 7 years or longer, based on challenge and serological studies. - DOI after vaccination with a killed panleukopenia vaccine was demonstrated to last for a minimum of 7.5 years [bib_ref] Long-term immunity in cats vaccinated with an inactivated trivalent vaccine, Scott [/bib_ref]. - While most cases of feline panleukopenia are caused by infection with FPV, variants of canine parvovirus (CPV-2a, CPV-2b and CPV-2c) have emerged that infect cats and may cause disease [bib_ref] Canine parvovirus -a review of epidemiological and diagnostic aspects with emphasis on..., Decaro [/bib_ref]. Certain current FPV vaccines afford some protection against these CPV variants. - Maternally derived antibody (MDA) interferes with active immunization for varying periods of time in the kitten, depending on the titre of colostral antibody and the amount of antibody absorbed during the first hours after birth. - The 'window of susceptibility' is defined as the period of time during which a kitten can be infected by field virus, but vaccines cannot immunize. By analogy with canine parvovirus, an immunity gap is assumed to exist, when antibody levels are too low to protect against natural infection, but still high enough to interfere with vaccination.

## E30
Journal of Small Animal Practice - Vol 57 - January 2016 -  2016 WSAVA
- After completing the kitten series at 16 weeks or older and vaccinating again at 26 or 52 weeks of age, revaccination need not be done more often than every 3 years. - The presence of serum antibody, regardless of titre, in an actively immunized cat over the age of 20 weeks is correlated with protection. - When vaccination is being used to control disease in the face of an outbreak in a shelter situation, the more rapid induction of immunity induced by MLV vaccines is of clinical advantage. - There is a very early onset of protection after vaccination with MLV products [bib_ref] Immunisation against panleukopenia: early development of immunity, Brun [/bib_ref].

## Precautions
- MLV FPV vaccines should not be used in wild animal species unless there is evidence to show that they are safe. - MLV FPV vaccines should never be used in pregnant queens because of the risk of transfer of virus to the fetus and fetal damage.
In some countries, inactivated FPV vaccines are licensed for use in pregnant queens, but in general, unnecessary administration of products to pregnant queens should be avoided. - MLV FPV vaccines should never be administered to kittens less than 4-6 weeks of age, to avoid damage to the cerebellum which is still developing in neonates. - MLV FPV vaccines should not be used in severely immunosuppressed individuals -although the risk appears small, with severe immunosuppression (for example with clinical FIV or FeLV infection or with the use of highly immunosuppressive drugs) failure to control viral replication could potentially lead to clinical signs after vaccination.

## Disease facts
- After infection, it takes 2-7 days for signs of disease to appear.
- Vomiting usually develops 1-2 days after the onset of fever. Diarrhoea may begin later, but is not always present. Dehydration develops rapidly, and an affected cat may sit at a water bowl, obviously thirsty, but without drinking. Terminal cases are hypothermic and may develop septic shock and disseminated intravascular coagulation. - In the environment, the virus can remain infectious for 1 year or more [bib_ref] Canine parvovirus: environmental effects on infectivity, Gordon [/bib_ref] so all facilities where infected animals have been present must be considered contaminated. Mechanisms and Duration of Immunity (DOI) - Protection afforded by FHV-1 (as well as FCV) vaccines is not as complete as that seen with the FPV vaccines. The other two feline core vaccines (FHV-1 and FCV) should not be expected to provide the same robust degree and duration of immunity as seen with the canine core vaccines or FPV. - Assessment of the DOI is difficult. Complete clinical protection is seen only shortly after vaccination, and the degree of protection decreases with time [bib_ref] Feline herpesvirus, Gaskell [/bib_ref]. - Immunity is far from solid after natural infection/disease and is of variable duration. - Persistence of antibody titre after vaccination with a killed FHV-1 vaccine was demonstrated for 3 years [bib_ref] Duration of immunity in cats vaccinated with an inactivated feline panleukopenia, herpesvirus..., Scott [/bib_ref] , but antibody titre for FHV-1 does not correlate well with protection [bib_ref] Feline herpesvirus, Gaskell [/bib_ref]. - Protection from challenge with virulent FHV-1 7.5 years after vaccination with two doses of killed vaccines was not complete, but was similar to protection after 1 year with the killed product [bib_ref] Long-term immunity in cats vaccinated with an inactivated trivalent vaccine, Scott [/bib_ref]. - After completing the kitten series at 16 weeks or older and vaccinating again at 26 or 52 weeks of age, revaccination need not be done more often than every 3 years in cats at low risk; however, cats at higher risk (e.g. those that regularly attend boarding catteries) should be revaccinated more frequently. - If booster vaccinations have lapsed in a previously well-vaccinated cat, a single injection is considered adequate to boost immunological memory. - No herpesvirus vaccine can protect against infection with virulent virus; FHV-1 will become latent and may be reactivated during periods of severe stress. The reactivated virus may cause clinical signs in vaccinated animals [bib_ref] Feline herpesvirus, Gaskell [/bib_ref] ; the virus may be shed, transmitted to susceptible animals and cause disease in susceptible kittens and cats [bib_ref] Feline herpesvirus, Gaskell [/bib_ref].

## E31
- Cell-mediated immunity plays an important role in protection, since the absence of detectable serum antibody levels in vaccinated cats does not necessarily indicate that cats are susceptible to disease. - MDA interferes with active immunization for varying periods of time in the kitten, depending on the titre of colostral antibody and the amount of antibody absorbed after birth. The primary course of vaccination is usually started at around 6-8 weeks of age. MDA interferes less with MLV intranasal (IN) vaccines than parenterally administered MLV products. It would be expected that the IN vaccines will immunize earlier than the parenteral vaccines in kittens with MDA. - In breeding catteries, infections mostly appear in kittens prior to weaning, typically between 4-8 weeks of age, as MDA wanes. In most cases, the source of infection is the queen, whose latent virus is reactivated due to the stress of parturition and lactation.

## Precautions
- Modified live parenteral FHV-1 and FCV vaccines retain some pathogenic potential and may induce disease if administered incorrectly (i.e. when accidentally aerosolized or ingested or inhaled from vaccine deposited on the skin/hair). - Upper respiratory disease signs are sometimes seen following intranasal vaccination.

## Disease facts
- Viral excretion starts as soon as 24 hours after infection and lasts for 1-3 weeks.
- Acute disease appears after 2-6 days and resolves within 10-14 days.
- The virus spreads along the sensory nerves and reaches neuronal cell bodies, particularly in the trigeminal ganglia, which are the main sites of latency. Most cats become lifelong latent carriers, shedding the virus periodically, upon stressful events [bib_ref] Feline herpesvirus, Gaskell [/bib_ref]. In contrast, shedding of FCV is continuous for a period of months after infection. Herpesvirus genomic DNA persists in the nucleus of infected neurons without replication. - In the environment, the virus is labile and inactivated by commonly used disinfectants.

## Mechanisms and duration of immunity (doi)
- There is considerable antigenic variability amongst FCV strains. Prior infection with one strain can significantly reduce the acute clinical signs upon exposure to a heterologous strain, and also oral virus shedding. In general, the level of heterologous protection depends on the pair of virus strains examined. - Virus neutralizing antibodies first appear approximately 7 days after infection; their titre correlates well with protection against homologous challenge. Cats may also be protected in the absence of serum antibody, since local secretory IgA antibody and cellular responses have been demonstrated to provide protection in vaccinated cats. - After vaccination with a killed and adjuvanted FCV vaccine, antibody was shown to persist for at least 4 years [bib_ref] Duration of immunity in cats vaccinated with an inactivated feline panleukopenia, herpesvirus..., Scott [/bib_ref]. - Protection from challenge with virulent FCV 7.5 years after vaccination with two doses of killed adjuvanted vaccine was incomplete, but was similar to protection after 1 year with the killed product [bib_ref] Long-term immunity in cats vaccinated with an inactivated trivalent vaccine, Scott [/bib_ref]. - Protection afforded by FCV (as well as by FHV-1) vaccines is not as complete as that seen with the FPV vaccines. The two core respiratory vaccines should not be expected to provide the same robust degree and duration of immunity as seen with FPV or the canine core vaccines. Reinfection with FCV of differing strains is possible in vaccinated cats. - After completing the kitten series at 16 weeks or older and vaccinating again at 26 or 52 weeks of age, revaccination need not be done more often than every 3 years in cats at low risk; however, cats at higher risk (e.g. those that regularly attend boarding catteries) may be revaccinated more frequently. - It is recommended that vaccines that contain the same virus strains be used in the kitten series. - MDA is important for protection during the first weeks of life and may interfere with vaccination. The average half-life of MDA was determined to be 15 days with persistence for 10-14 weeks [bib_ref] Transfer and decline of maternal antibody to feline calicivirus, Johnson [/bib_ref]. In a field study, about 20% of kittens at 6 weeks of age had no detectable antibodies against a widely used vaccine strain [bib_ref] A field trial to assess the effect of vaccination against feline herpesvirus,..., Dawson [/bib_ref]. MDA interferes less with MLV given intranasally than with parenterally administered MLV products. It would be expected that the IN vaccines will immunize earlier than the parenteral vaccines in kittens with MDA.

## Precautions
- Upper respiratory disease signs may be seen occasionally as a complication of intranasal vaccination [bib_ref] Effects of a single dose of an intranasal feline herpesvirus 1, calicivirus,..., Lappin [/bib_ref] [bib_ref] Feline panleukopenia virus, feline herpesvirus-1, and feline calicivirus antibody responses in seronegative..., Lappin [/bib_ref]. - Because of the multitude of antigenically differing viruses circulating in the field, vaccine strain combinations have been chosen to cross-protect against severe clinical disease, but mild disease may still occur in vaccinated cats. - In contrast to FHV-1, which is shed intermittently after stressful events, shedding of FCV is continuous, but usually ceases after several months [bib_ref] Long-term analysis of feline calicivirus prevalence and viral shedding patterns in naturally..., Coyne [/bib_ref]. The impact of vaccination on shedding is controversial, with observations ranging from moderate reduction to extension of the period of virus shedding post infection. Live parenteral FCV vaccine strains can be shed, although infrequently.

## Disease facts
- FCV infection can cause acute oral and upper respiratory signs, but has also been associated with chronic gingivostomatitis, which may be immune-mediated. - The incubation period is 2-10 days. Oral ulceration (particularly of the margins of the tongue), sneezing and serous nasal discharge are the main signs. Acute oral and upper respiratory disease signs are mainly seen in kittens. - A distinct syndrome, the 'virulent systemic feline calicivirus (VS-FCV) disease' is occasionally described [bib_ref] Lethal outbreak of disease associated with feline calicivirus infection in cats, Coyne [/bib_ref]. The incubation period for this infection in cats exposed in shelters and hospitals is 1-5 days; in the home environment it may be up to 12 days. This disease appears to be more severe in adults than kittens. Vaccination with current vaccines does not protect cats against field infections, but some protection has been shown experimentally [bib_ref] Efficacy of a bivalent inactivated non-adjuvanted feline calicivirus vaccine: relation between in..., Poulet [/bib_ref] [bib_ref] A dual-strain feline calicivirus vaccine stimulates broader cross-neutralization antibodies than a single-strain..., Huang [/bib_ref]. This might be due to the inherent characteristics of the hypervirulent strains. There is a killed VS-FCV strain in a vaccine available in the USA that contains both 'traditional' and VS-FCV isolates and is reported to provide protection against homologous VS-FCV [bib_ref] A dual-strain feline calicivirus vaccine stimulates broader cross-neutralization antibodies than a single-strain..., Huang [/bib_ref]. It is not known if this strain of VS-FCV will provide protection against heterologous VS-FCV strains.

## Fact sheet: rabies vaccines

## Inactivated (killed) vaccines:
The use of killed vaccines is the rule for individual dog and cat protection and mass canine vaccination programmes. The killed vaccines are easier to manage than live preparations because of their stability at ambient temperatures, and accidents of self-inoculation do not represent a risk, as would be the case for MLV vaccines.

## Mechanisms and duration of immunity (doi)
- Canine and feline rabies is controlled mostly by the use of inactivated vaccines. However, in the USA and Europe recombinant canary pox vectored rabies vaccine is licensed and widely used in cats because it is not associated with the inflammation at the injection site caused by adjuvanted rabies vaccines ). All initial rabies vaccinations must be followed 1 year later by revaccination. Only after that second vaccination can the interval for revaccination be extended legally to 3 years with a product that has a 3-year DOI label. - DOI after natural infection cannot be assessed, because disease following street virus infection is fatal in the dog and cat. - DOI after vaccination with commercially available inactivated and recombinant products is 3 years, based on challenge and serological studies [bib_ref] Three-year duration of immunity in cats vaccinated with a canarypox-vectored recombinant rabies..., Jas [/bib_ref]. - First vaccination is not earlier than 12 weeks of age with revaccination 1 year later; antibody titres generally reach protective levels 4 weeks after vaccination. Where serological testing is required for legal purposes the interval between vaccination and testing is crucial and may be product-dependent. The product datasheet and legal requirements should be consulted. - Some vaccines are proven to protect against virulent rabies virus challenge for 3 years, but national or local legislation may call for annual boosters. The VGG encourages all legislators to consider scientific advances when formulating policy. Some vaccines (e.g. nationally produced products) may not reliably protect for more than 1 year. - The presence of serum antibody of 0.5 IU/ml in an actively immunized dog over the age of 16 weeks is correlated with protection.
Achieving this concentration (0.5 IU/ml) is also considered a legal requirement for pet travel to some countries which include serological testing post-vaccination in their protocol for movement of pets. Disease Facts - Signs of disease appear between 2 weeks and several months after infection, depending upon the site of infection (transmission is generally by bite or scratch). Any unexplained aggressive behaviour or sudden behavioural change must be considered suspicious. - The disease manifests itself as a 'furious' or a 'dumb' form. Signs of the classical 'furious' form of rabies include reduced palpebral, corneal and pupillary reflexes, strabismus, dropped jaw, salivation, pica, seizures, twitching, tremors, disorientation, aimless pacing, aimless snapping and biting, exaggerated emotional responses (irritability, rage, fear), photophobia, as well as ataxia and paralysis, ultimately followed by coma and death from respiratory arrest. The 'dumb' form of rabies is more common in dogs than cats and presents as lower motor neuron paralysis that progresses from the site of the bite injury to involve the entire central nervous system. The paralysis rapidly leads to coma and death from respiratory failure. - In the environment, the virus quickly loses infectivity, and is readily inactivated using detergent-based disinfectants.

## Frequently asked questions (faqs)
QUESTIONS RELATED TO VACCINE PRODUCTS 1. May I give a MLV product to a wild, exotic species or to a domestic species other than to the ones which the vaccine was licensed to protect? No, never give MLV vaccines unless they have been shown to be safe in that species. Many MLV vaccines have caused disease in animal species other than those for which they had been licensed. Even worse, the vaccine could be shed from the wild animals, regain virulence through multiple passages and cause disease even in the target species for which it had been developed.
A safe and effective vaccine for species that are susceptible to CDV is the canarypox virus-vectored recombinant CDV vaccine that is available as a monovalent product for ferrets or a combination product for dogs. The monovalent vaccine is used in many wild and exotic species susceptible to CDV, but is only available in certain countries.

## May i vaccinate a puppy that is at high risk of getting cdv with a human measles vaccine?
No. Due to an insufficient amount of virus, the human MV vaccine is not immunogenic in the puppy. Measles virus vaccines made specifically for the dog (sometimes combined with CDV and additional viral components) may give temporary protection at an earlier age than a CDV vaccine. At 16 weeks or older, the puppy must be vaccinated with a CDV vaccine, to achieve permanent immunity.

## Can certain vaccines immunize pups having maternally derived antibody (mda) against cdv at an earlier age?
Yes. The heterotypic measles vaccine for dogs will immunize pups about 4 weeks earlier than the MLV-CDV vaccines. Similarly, the canarypox vectored recombinant CDV vaccine will immunize approximately 4 weeks earlier than some MLV vaccines and there are some high titre MLV vaccines (i.e. vaccines containing a greater mass of virus in the vaccine ampoule) which also immunize at an earlier age in puppies with MDA.

## I know that maternally derived antibodies (mda) can prevent active immunization with mlv vaccines -but can they also block immunity to killed vaccines?
Yes. MDA can block certain killed vaccines. If the killed product requires two doses, as is often the case, and the first dose is blocked by MDA, then the second dose will not immunize. In this circumstance, the second dose will prime (if not blocked), and a third dose is required to immunize and boost. This is not true for MLV vaccines, where in the absence of MDA it only takes a single dose to prime, immunize, and boost. Nevertheless two doses are often recommended, particularly in young animals, to be sure one is given when MDA has waned and cannot block. That is why in the puppy or kitten series, the last dose should be given at 16 weeks of age or older. 5. I have been told that certain canine MLV combination core products need only be given twice, with the last dose at an age as young as 10 weeks. Is that accurate?
The VGG is aware that certain canine vaccines are licensed for such an 'early finish' in order to allow pups the benefit of early socialization. The VGG accepts the importance of puppy socialization, but has reservations about the immunological validity of this approach to vaccination. No combination core product currently available will immunize an acceptable percentage of puppies (particularly not against CPV-2) when the last dose is given at 10 weeks of age. The VGG advises that wherever possible the last dose should be given at 16 weeks of age or older, regardless of the number of doses given earlier. The VGG recommends that owners of pups that have not completed a full puppy vaccination series carefully control the exposure of their pup to environments outside of the home and only permit contact with healthy and fully vaccinated dogs.

## For how long can a reconstituted mlv vaccine sit at room temperature without losing activity?
At room temperature, some of the more sensitive vaccines (e.g. CDV, FHV-1) will lose their ability to immunize in 2-3 hours, whereas other components will remain immunogenic for several days (e.g. CPV, FPV). The VGG recommends that MLV vaccines, after reconstitution, should be used within 1 to 2 hrs.

## 67.
If an animal has gone beyond the time that is generally considered to be the minimum DOI for the core vaccine (7 to 9 years for CDV, CPV-2, CAV-2; 7 years for FPV), do I have to start the series of vaccinations again (multiple doses 2-4 weeks apart)?
No. For MLV vaccines, multiple doses are only required for puppies or kittens which have MDA. The VGG is aware that many data sheets do advise re-starting a vaccination series, but does not endorse this practice which is inconsistent with fundamental immune system function and the principles of immunological memory.

## Should i vaccinate a cat infected with felv and/or fiv infection?
A FeLV or FIV positive cat that is clinically well would ideally be housed indoors away from other cats to minimize the risk of exposure to infectious disease. However, if it were deemed necessary to vaccinate with core components (FPV, FCV and FHV-1) expert groups currently recommend that this should be with killed (not MLV) vaccines. Such cats should not be vaccinated against FeLV or FIV. A FeLV or FIV positive cat with clinical illness should not be vaccinated. In some countries there is a legal requirement for rabies vaccination that would also include retrovirus-infected cats.

## Where should i inject vaccine into a cat?
Feline vaccines (particularly adjuvanted products) should not be given into the inter-scapular region. In the USA the practice of giving separate injections of rabies vaccine into the distal right hind limb, FeLV vaccine into the distal left hind limb and core FPV/FCV/ FHV-1 vaccines into a distal forelimb is practiced. Alternative sites for subcutaneous injection are into the distal tail or over the lateral thoracic or abdominal wall. These options are discussed further in the main text of this document. Whichever site is chosen, the vaccine must be administered subcutaneously and not intramuscularly. Importantly, the anatomical site of feline vaccination should be rotated so that vaccines are not given repeatedly to one location. This may be achieved by recording the site of vaccination for each individual on each occasion and rotating between these, or by adopting a practice policy to use one anatomical location each year.

## Does severe nutritional deficiency affect the immune response to vaccines?
Yes. It has been shown that certain severe deficiencies of vitamins and trace minerals (e.g. Vitamin E/Selenium) can interfere with the development of a protective immune response in puppies. Known or suspected nutritional deficiencies should be corrected by appropriate nutritional supplementation and the animals should be revaccinated to ensure there is adequate protective immunity.

## If a puppy or kitten fails to receive colostrum will it have any passive antibody protection from the dam?
Depending on the antibody titre of the dam they will have little or, most likely, no protection as approximately 95% or more of the passive antibody for the newborn puppy and kitten is obtained from the colostrum which is absorbed via the intestine into systemic circulation for up to 24 hours after birth.
72. Should a puppy or kitten that fails to receive colostrum be vaccinated during the first few weeks of life since they will not have maternally derived antibody to block active immunization? No. Puppies and kittens less than 4-6 weeks of age should not be vaccinated with the MLV core vaccines. Certain of the modified live vaccine viruses when given to puppies/kittens less than 2 weeks of age and without MDA can infect the central nervous system and/or cause disease and possibly death of the animal. This occurs because there is little or no thermoregulatory control of body temperature during the first week or more after birth, thus innate and adaptive immunity is significantly impaired.

## How can these colostrum-deprived young animals be protected from the core diseases?
Artificial colostrum can be fed if the puppy or kitten is less than 1 day old. Artificial colostrum is 50% milk replacer (e.g. Esbilac TM or other similar product) and 50% immune serum (preferably from the dam or other well vaccinated animal living in the same environment as the dam). If pups or kittens are older and 1 day of age, serum from a well immunized adult animal (free of infectious disease) can be given subcutaneously or intraperitoneally or citrated plasma can be given intravenously. Depending on size of the animal, approximately 3 to 10 ml of serum or plasma should be administered twice daily for up to 3 days.

## At what age can one stop vaccinating dogs?
For core vaccines, the current recommendation is for lifelong revaccination no more frequently than every 3 years and if non-core vaccines are chosen for use, these are generally given annually. One can use serological testing in any adult dog to confirm protection Journal of Small Animal Practice - Vol 57 - January 2016 -  2016 WSAVA E41 against core diseases (i.e. CDV, CAV and CPV-2) and elect not to revaccinate that animal. Current advice is that serological assessment is performed every 3 years, but in dogs older than 10 years, this should be done annually. In many countries there is also a legal requirement to vaccinate against rabies at particular intervals.

## What protocol is recommended for an unvaccinated adult dog?
Core vaccination with a single dose of MLV vaccine (CDV, CAV-2, CPV-2) plus rabies in endemic areas. There is no need to give two doses. Revaccination (or serological testing for CDV, CAV and CPV-2) no more frequently than every 3 years thereafter. Non-core vaccines should be selected based on a risk:benefit analysis for that individual animal. Non-core vaccines would require two doses given 2-4 weeks apart and then an annual booster.

## For an adult dog with an unknown leptospira vaccination history, what's the recommended vaccination protocol? is it still two doses 2-4 weeks apart as in puppies?
Yes, this dog would require two doses of vaccine given 2-4 weeks apart and then annual revaccination thereafter.

## What protocol is recommended for an unvaccinated adult cat?
For an adult cat that has never been vaccinated, the VGG recommends core vaccination with two doses of MLV vaccine (FPV, FCV, FHV-1) plus one dose of rabies vaccine in endemic areas. Revaccination (or serological testing for FPV) no more frequently than every thereafter for a low-risk cat, or revaccination no more frequently than every 3 years for FPV and annually for FHV-1 and FCV for a high-risk cat. Non-core vaccines should be selected based on a risk:benefit analysis for that individual animal.

## Should a cat be vaccinated if it already has signs of upper respiratory disease?
A cat with current clinical disease should not be vaccinated. Once it has recovered, the cat should have some natural immunity to FCV or FHV (or both if both agents were involved in causing the respiratory disease), but such immunity is never sterilizing (even after vaccination). There is no indication NOT to vaccinate a cat that has recovered from a respiratory viral infection. A trivalent vaccine will protect against FPV and also against the respiratory virus (FHV-1 or FCV) that was not involved in causing the earlier respiratory disease.
79. Power cuts are not uncommon in parts of our country and they can last for 2-3 days. What should one do as regards any vaccine in the fridge at the time -is it OK to use? MLV vaccine that has not been stored at appropriate temperature for 2-3 days should not be used. Some of the components of these vaccines (e.g. CDV) are temperature sensitive and there may have been inactivation of the virus. If you are in any doubt, you should contact the manufacturer for advice.

## Questions about the use of serological testing

## Are serum antibody titres useful in determining vaccine-induced immunity?
Yes. This is particularly the case for CDV, CPV-2 and CAV-1 in the dog, FPV in the cat and (for legal purposes) rabies virus in the cat and dog. Serum antibody titres are of limited or no value for the other vaccines. Assays for CMI are of little or no value for any of the vaccines for various technical and biological reasons. Such factors are less of an issue for serological tests where it is much easier to control many of the variables. However, discrepant results are still obtained, depending on the quality assurance program of the given laboratory.

## How long after cpv-2/cdv vaccination should you wait before measuring protective antibody concentrations using inclinic tests?
This question is most relevant for puppies, because adult dogs are likely already to have serum antibodies present at the time of booster vaccination, regardless of how long an interval there has been since they were last vaccinated. If a puppy receives its final primary vaccine at 16 weeks of age, then it may be tested from 20 weeks of age onwards. Any antibody present at that stage cannot be of passive, maternal origin and therefore indicates that the puppy is actively protected.

## Why don't the vgg recommend routine rabies antibody testing?
For many veterinarians, this question may be of little practical consequence, as regular rabies vaccination of dogs and cats is a legal requirement in many countries, irrespective of any titre results. Rabies antibody testing is only required in certain situations related to international pet travel. The international rabies vaccines are highly efficacious and it is generally considered that there is no need to demonstrate immunity post vaccination.
[fig] FACT: SHEET: FELINE HERPESVIRUS (FHV)-1 VACCINES Types of Vaccines Available Modified Live Virus (MLV) Vaccines: These preparations contain attenuated FHV-1 (feline rhinotracheitis virus, occurring as a single serotype) at various titres, without adjuvant. There are injectable preparations and others for intranasal application, alone or in combination with other vaccinal antigens (always with FCV). Inactivated (Killed) Vaccines: Adjuvanted killed vaccines are available. [/fig]
[table] E17 Table 1: Journal of Small Animal Practice  Vol 57  January 2016   2016 WSAVA WSAVA Canine Vaccination Guidelines Non-core. Use of CPiV (MLV-intranasal) is preferred to the parenteral product as the primary site of infection is the upper respiratory tract. [/table]
[table] Table 2: Where the recommendations in this table are not consistent with those on datasheets [EB2] the level of evidence supporting the recommendation is given.The VGG did not consider the following products that have restricted geographical availability: Crotalus atrox (western rattlesnake vaccine) and Crotalux adamanteus (eastern rattlesnake vaccine) -Conditional USDA License Babesia vaccine (soluble parasite antigen from B. canis in saponin) -EU Licensed Canine herpesvirus vaccine -EU Licensed Leishmania vaccines -licensed in Brazil and the EU WSAVA Guidelines on Canine Vaccination for the Shelter Environment Intranasal or oral vaccine is strongly recommended in the shelter situation. Intranasal or oral vaccines MUST NOT be administered parenterally as this may lead to severe adverse reactions or death. [/table]
[table] Table 3: WSAVA Feline Vaccination Guidelines Core. Only FeLV-negative cats should be vaccinated. FeLV testing must be performed prior to vaccine administration to avoid unnecessary administration of vaccine. Core. Only FeLV-negative cats should be vaccinated. FeLV testing must be performed prior to vaccine administration Journal of Small Animal Practice  Vol 57  January 2016   2016 WSAVA Core. Vaccination is most appropriately used as part of a control regime for animals in multicat environments where infections associated with clinical disease have been confirmed. Inadvertent conjunctival inoculation of vaccine has been reported to cause clinical signs of infection. Where the recommendations in this table are not consistent with those on datasheets [EB2] the level of evidence supporting the recommendation is given. [/table]
[table] Table 4: WSAVA Guidelines on Feline Vaccination for the Shelter Environment [/table]
[table] Table 5: weeks, 13 weeks, 17 weeks then 26 or 52 weeks [/table]
[table] Table 7: Use of Serological Testing in a Shelter Infectious Disease Outbreak [/table]