Immunization of adults: Canadian Immunization Guide
Introduction
Prevention of infection by immunization is not just for children; adults require immunization to restore waning immunity against some vaccine preventable diseases and to establish immunity against other diseases that are more common in adults. In addition, immunization of adults prevents infection and, therefore, subsequent exposure of young children and others at increased risk of vaccine preventable diseases. For example, adults who are in contact with infants should be prioritized to receive pertussis and influenza vaccination to reduce the risk of transmission of these infections to infants who are too young to be fully protected. Some vaccines are needed by all adults and other vaccines may be required due to individual risk resulting from occupation, travel, underlying illness, lifestyle or age.
In recent years, new vaccines such as herpes zoster and human papillomavirus have become available for adults. Despite these advances, the vaccination rates of adults in Canada are low, with the result that many adults remain vulnerable to vaccine preventable diseases.
Common reasons for incomplete immunization in adulthood include:
- lack of recognition of the importance of adult immunization
- lack of recommendations from health care providers
- lack of health care provider's knowledge about adult immunization and recommended vaccines
- misrepresentation and misunderstanding of the risks of vaccine and benefits of disease prevention in adults
- lack of understanding of vaccine safety and efficacy
- missed opportunities for vaccination in health care providers' offices, hospitals and nursing homes
- lack of publicly funded vaccine and reimbursement to vaccine providers
- lack of coordinated immunization programs for adults
- lack of regulatory or legal requirements
- fear of injections
- lack of availability of up-to-date records and recording systems
Adult immunization is an emerging issue that has seen an increasing emphasis in clinical care and health professional training programs.
Health care provider responsibilities
Health care providers have a responsibility to ensure that adults under their care have continuing and updated protection against vaccine preventable diseases through appropriate immunization. When considering immunization, the person's medical history will help to determine whether other immunizations are needed in addition to routinely recommended vaccines. Refer to  and  in Part 3 for further information on how health conditions may modify vaccine recommendations.
Health care providers should provide adults under their care with factual information about immunization, including:
- information about vaccines
- expert recommendations regarding the use of vaccines
- benefits and risks of vaccination
- cost of the vaccine if it is not publicly funded
- possible consequences of declining a vaccine
- where vaccine can be obtained if the health care provider is unable to provide the vaccine
When more than one dose of a vaccine is required for optimal protection, the health care provider should arrange follow-up to encourage completion of the vaccine series.
Strategies to improve vaccine uptake in adults
All adults should be counselled concerning their immunization status. Opportunities for general immunization counselling of adults include:
- new patient encounters
- periodic health examinations
- pregnancy and the immediate post-partum period
- visits for chronic disease management
- assessment of new immigrants
- parents attending their child's vaccination visits
- hospitalization, especially when diagnosed with a chronic disease
- management protocols on admission to nursing homes, long-term care institutions, and acute care institutions
- management protocols on admission to health professional training programs
- new employee assessments in day care, health care and health care-related facilities
- persons requesting specific vaccination(s)
- persons with evidence of risk taking behaviour, such as illicit drug use or a sexually transmitted infection
- individuals requesting advice concerning travel
Health care providers should regularly review individuals under their care to ensure that the person's immunization status is up to date and that they have been made aware of new vaccines that are or may be indicated for them. Practitioners should routinely audit immunization records during clinical encounters; scheduling record audits on a set birthday, for example, to coincide with a mid-decade birthday (i.e., 25, 35 years of age, etc.), is one effective reminder strategy. Health care institutions should have policies addressing immunization issues for patients and personnel.
Additional effective strategies for increasing the uptake of immunization by adults include patient and health care provider education about indicated prevention practices, and increasing accessibility to immunization through immunization clinics and greater engagement of non-physician staff in the execution of immunization programs. A sample adult immunization record and information resources for adult immunization are available on the  website.
Recommended immunization for adults
All adults in Canada without contraindications should be routinely immunized against vaccine preventable diseases. Routinely recommended adult immunizations are summarized in . Recommended immunization schedules for adults who have no record or an uncertain immunization history are available in  in Part 1.
In addition to routinely recommended immunization, certain vaccines are recommended for adults in specific risk situations. These recommendations are summarized in . International travellers and workers in specific risk situations require assessment of immunization status, completion of routinely recommended vaccine series, and booster doses as necessary. Refer to , ,  and  in Part 3; and  in Part 4 for additional information.

# Diphtheria toxoid-, tetanus toxoid-, containing vaccine
All adults in Canada should be immunized against diphtheria and tetanus. Booster doses of diphtheria and tetanus toxoid-containing vaccine are recommended every 10 years. Refer to  and  in Part 4 for additional information.

# Herpes zoster (shingles) vaccine
A two dose series of Recombinant Zoster Vaccine, (RZV) is recommended for adults 50 years of age or older without contraindications, including those who have previously been immunized with Live Zoster Vaccine (LZV), or who have had a previous episode of herpes zoster (HZ). Re-immunization with RZV may be considered at least one year after LZV or at least one year after an episode of HZ. In immunocompetent adults in whom RZV is contraindicated or when the vaccine is unavailable or inaccessible, LZV may be considered. Adults aged 50 years and older who are known to be *varicella zoster virus- seronegative should receive univalent varicella (chickenpox) vaccine, rather than herpes zoster (shingles) vaccine. Routine testing of adults aged 50 years and older for *varicella zoster virus- antibody prior to immunization is not recommended. Refer to -vaccine.html) in Part 4 for additional information.

# Human papillomavirus vaccine
Bivalent or quadrivalent or nonavalent human papillomavirus (HPV) vaccine is recommended for women up to and including 26 years of age and may be administered to those 27 years of age and older who are at ongoing risk of exposure. Quadrivalent or nonavalent HPV vaccine is recommended for men up to and including 26 years of age and may be administered to men 27 years of age and older who are at ongoing risk of exposure. Refer to  in Part 4 for additional information.

# Influenza vaccine
Seasonal influenza vaccine is recommended annually for all adults without contraindications, with particular focus on individuals who are at high risk of influenza-related complications or hospitalization, who are capable of transmitting influenza to those at high risk, who provide essential community services and who are in direct contact during culling operations with poultry infected with avian influenza. Refer to  in Part 4 for additional information.

# Measles-mumps- rubella vaccine
Combined measles-mumps-rubella (MMR) vaccine is recommended for vaccination of adults born in or after 1970 susceptible to one or more of these viruses. Although adults born before 1970 are assumed to have acquired natural immunity, those at the greatest risk of measles or mumps exposure, such as travellers, health care workers, students in post-secondary educational settings, and military personnel, may require immunization. If MMR vaccine is indicated for a pregnant woman, it should be provided after delivery, preferably prior to discharge from hospital. Refer to ,  and  in Part 4 for additional information including criteria for determining susceptibility/immunity to measles, mumps and rubella.

# Meningococcal vaccine
Healthy adults up to and including 24 years of age should receive meningococcal vaccine if it was not received in adolescence. Either a meningococcal conjugate monovalent or a meningococcal conjugate quadrivalent vaccine, depending on local epidemiology and programmatic considerations, is recommended for young adults, even if they have previously been vaccinated as an infant or toddler. In addition, multicomponent meningococcal vaccine may be considered on an individual basis to protect against invasive meningococcal disease caused by relevant serogroup B strains. Adults with specific risk conditions (refer to  ) are recommended to receive meningococcal conjugate quadrivalent vaccine, multicomponent meningococcal vaccine or both vaccines, depending on the risk situation. Refer to  in Part 4 for additional information.

# Pertussis-containing vaccine
All adults (18 years of age and older) should receive one dose of acellular pertussis-containing vaccine (tetanus, diphtheria  in Part 4 for additional information.

# Pneumococcal vaccine
Pneumococcal polysaccharide 23-valent (Pneu-P-23) vaccine is recommended for all adults 65 years of age and older. For additional information about the immunization of adults at highest risk of invasive pneumococcal disease refer to ,  in Part 4, and  and  in Part 3.

# Poliomyelitis vaccine
All adults in Canada should be immune to polio. For previously unimmunized adults, a primary series of inactivated poliomyelitis vaccine (IPV) should be provided at the time of immunization with a tetanus and diphtheria toxoid-containing vaccine. For adults that have previously received a primary series of tetanus and diphtheria toxoid-containing vaccine, IPV-containing vaccine can be provided at the time of routine tetanus and diphtheria toxoid-containing vaccine booster immunization. Unimmunized or incompletely immunized adults at increased risk of exposure should complete a primary series of IPV-containing vaccine; previously immunized adults at increased risk of exposure should receive a single lifetime booster dose of IPV-containing vaccine. Refer to  and  in Part 4 for additional information.

# Varicella (chickenpox) vaccine
Univalent varicella vaccine is recommended for susceptible adults 18 to 49 years of age. Refer to  in Part 4 for additional information. For adults 50 years of age and older refer to -vaccine.html) in Part 4.
- Booster dose every 10 years
- 50 years of age and older previously received LZV - 2 doses RZV, at least 1 year after immunization with LZV
- 50 years of age and older previous episode of HZ - 2 doses RZV, at least 1 year after episode of HZ
- immunocompetent individuals 50 years of age and older where RZV is contraindicated, unavailable or inaccessible - 1 dose LZV
- Men up to and including 26 years of age - HPV4 or HPV9 vaccine
- Born before 1970 - consider immune
- Adults who will be in close contact with young infants should be immunized as early as possible
- One dose of Tdap vaccine should be administered in every pregnancy, ideally between 27 and 32 weeks of gestation.
- If vaccine is indicated, pregnant women should be immunized after delivery
- Known seronegative adults 50 years of age and older - 2 doses - routine testing is not advised
HPV
human papillomavirus
HPV2
human papillomavirus bivalent vaccine
HPV4
human papillomavirus quadrivalent vaccine
HPV9
human papillomavirus nonavalent vaccine
LZV
live zoster vaccine
RZV
recombinant zoster vaccine
- who are long-term travellers to high prevalence countries (in exceptional circumstances as noted above)
- Consider use for prevention of travellers' diarrhea in adults:
	+ with chronic diseases at risk for complications
	+ at increased risk of acquiring travellers' diarrhea
	+ who are immunosuppressed
	+ with a history of repeated severe travellers' diarrhea
- malignant hematologic disorders
- HIV
- anatomic or functional asplenia or hyposplenism
- solid organ transplant recipients
- cochlear implant recipients
- who are immigrants from HA endemic areas
- who are household or close contacts of children adopted from HA endemic countries
- in communities or populations at risk of outbreaks or in which HA is highly endemic
- who are household or close contacts of proven or suspected cases of HA
- with occupational or lifestyle risk for exposure
- with chronic liver disease from any cause, including those infected with hepatitis B and C
- receiving plasma-derived replacement clotting factors
- who are household or sexual contacts of acute HB cases and HB carriers, including close contacts of children adopted from HB endemic countries if the adopted child is HBsAg positive
- with occupational or lifestyle risk for exposure
- travelling to HB endemic areas
- in communities or populations in which HB is highly endemic
- who are residents of institutions for the developmentally challenged or inmates of correctional facilities
- with chronic liver disease, including those infected with hepatitis C
- with chronic renal disease, including patients on chronic dialysis
- hemophiliacs and other people who receive repeated infusions of blood or blood products
- who have undergone hematopoietic stem cell transplantation or are awaiting solid organ transplant
- who have congenital immunodeficiencies
- who are HIV-infected
- Bivalent HPV vaccine may be considered for women 27 years of age and older at ongoing risk of exposure
- capable of transmitting influenza to individuals at high risk
- who provide essential community services
- in direct contact during culling operations with poultry infected with avian influenza
- travelling to endemic area(s) during transmission season with specified exposure risks
	+ If susceptible and at increased risk of exposure (travellers to destinations outside of Canada, health care workers, students in post-secondary educational settings, and military personnel) - 2 doses, at least 4 weeks apart.
- Recommended for adults born before 1970 if:
	+ non-immune military personnel or health care workers - 2 doses, at least 4 weeks apart
	+ non-immune travellers - 1 dose
	+ non-immune students - consider 1 dose
- who are travellers:
	+ for whom meningococcal vaccine is recommended or required, including travellers to sub-Saharan African and pilgrims to the Hajj in Mecca, Saudi Arabia
	+ to an area with a hyperendemic strain or an outbreak that is known to be caused by a serogroup that can be prevented by the vaccine
- at high risk of meningococcal disease due to medical conditions:
	+ anatomic or functional asplenia or hyposplenism (including sickle cell disease)
	+ congenital complement, properdin, factor D or primary antibody deficiencies
	+ acquired complement deficiency due to receipt of the terminal complement inhibitor eculizumab
	+ should be considered for adults who are HIV-infected
- who are close contacts of a case of invasive meningococcal disease caused by a vaccine preventable serogroup
- who are at increased risk of IPD due to lifestyle factors:
	+ persons with alcoholism
	+ smokers
	+ persons who are homeless
	+ should be considered for individuals who use illicit drugs
- who are at high risk of IPD due to an underlying medical condition:
	+ asthma requiring regular medical care
	+ chronic cerebral spinal fluid leak
	+ chronic neurologic condition that may impair clearance of oral secretions
	+ cochlear implants (including adults who are to receive implants)
	+ chronic cardiac or pulmonary disease
	+ diabetes mellitus
	+ chronic kidney disease
	+ chronic liver disease (including hepatic cirrhosis due to any cause)
- sickle cell disease or other hemoglobinopathies
- congenital immunodeficiencies involving any part of the immune system, including B-lymphocyte (humoral) immunity, T-lymphocyte (cell) mediated immunity, complement system (properdin or factor D deficiencies), or phagocytic functions
- HIV infection
- immunosuppressive therapy including use of long-term corticosteroids, chemotherapy, radiation therapy, post-organ transplant therapy, and biologic and non-biologic immunosuppressive therapies for rheumatologic and other inflammatory diseases
- malignant neoplasms including leukemia and lymphoma
- solid organ or islet cell transplant (candidate or recipient)
- nephrotic syndrome
- following HSCT
- health care workers who have close contact with individuals who might be excreting wild type or vaccine type poliovirus
- members of communities or specific population groups with disease caused by polio
- people who come in close contact with those who may be excreting poliovirus such as people working with refugees, military personnel and people on humanitarian missions in endemic countries
- laboratory workers handling specimens that may contain poliovirus
- family or close contacts of internationally adopted infants who may have been or will be vaccinated with oral polio vaccine (OPV)
For previously unimmunized adults - primary series of IPV-containing vaccine
- with lifestyle risk of exposure
- travelling to high-risk areas with specified exposure risks
- who have ongoing household or intimate exposure to a *S. typhi- carrier
- with occupational risk of exposure
- with occupational risk of exposure
Consider immunization of healthy adults aged 60 years and over if travel to areas with risk of yellow fever transmission cannot be avoided and a high level of protection against mosquito exposure is not feasible.
Based on a case-by-case assessment of benefit versus risk, the use of a one-time booster dose is recommended for certain individuals.
Re-immunization every 10 years is recommended for:- laboratory personnel working with YF virus unless measured neutralizing antibody titre to yellow fever virus confirms ongoing protection
- HIV-positive individuals who are travelling to countries with risk of YF transmission
Choice of meningococcal vaccine(s) varies with risk situation. Refer to  in Part 4 for additional information.
BCG
Bacille Calmette-Guerin
HBsAg
hepatitis B surface antigen
HA
Hepatitis A
HB
Hepatitis B
Hib
*Haemophilus influenzae- type b
HIV
human immunodeficiency virus
HSCT
hematopoietic stem cell transplantation
IPD
invasive pneumococcal disease
IPV
inactivated poliomyelitis vaccine
LZV
live zoster vaccine
OPV
-ral live poliomyelitis vaccine
RZV
recombinant zoster vaccine
TB
tuberculosis
Tdap
tetanus toxoid, diphtheria toxoid (reduced), acellular pertussis (reduced) - containing vaccine