Interim guidance on continuity of immunization programs during the COVID-19 pandemic
Preamble
 As a public health emergency of international concern, the coronavirus disease 2019 (COVID-19) pandemic (caused by the novel SARS-CoV-2 virus) has already impacted many aspects of healthcare delivery. Within Canada, all provinces and territories have initiated a range of public health measures to mitigate the transmission of SARS-CoV-2 and reduce the impact of the outbreak on healthcare systems; in some cases, this includes deferral of non-essential medical visits.  Immunizations, particularly in infants and toddlers, are essential. If capacity is not sufficient to maintain all routine programs, emphasis should be put on the  and booster doses for children aged less than two years.
 Disruption of immunization services, even for short periods, will result in an accumulation of susceptible individuals, and a higher likelihood of vaccine-preventable disease (VPD) outbreaks. Such outbreaks may result in VPD-related deaths and an increased burden on healthcare systems already strained by the response to the COVID-19 outbreak.  Moreover, once COVID-19 public health measures are relaxed and international borders are re-opened, risk for VPDs may increase as people start to travel or congregate again in settings where diseases are readily transmitted. 
 There is evidence that some individuals who miss routine immunizations at the scheduled time might not catch up later. Those who do seek catch-up immunization will add to increased volumes and pressures on the healthcare system during extended pandemic recovery phases, when other clinic visits will be resuming more actively.  In addition, those seeking catch-up immunization could be subject to prolonged wait times and vaccine availability issues. 
 Some of the risks of COVID-19 transmission at immunization visits can be mitigated by  to protect both healthcare providers and the public.  These include child and parent screening prior to visits,  for parents, physical distancing between patients at the clinic, scheduling considerations, and personal protective equipment for healthcare providers in ambulatory settings according to provincial, territorial or national guidelines which may change with transmission risk over the course of the pandemic. Immunization clinics for healthy individuals can occur early in the day, before appointments for sick patients, or having healthy child and sick child visits at separate locations.  Vaccines should not be administered by health professionals without training, as this could result in immunization errors.
 This guidance was prepared by the Public Health Agency of Canada in consultation with the National Advisory Committee on Immunization and the Canadian Immunization Committee, and should be considered in concert with provincial and territorial policies on continuity of immunization programs during the COVID-19 pandemic, and as routine services begin to resume.
Defer immunizations in symptomatic individuals
 Immunization settings should consider COVID-19 screening prior to appointments in order to reduce risks to healthcare providers and other patients.

# Those with symptoms of an acute respiratory infection:
 During the COVID-19 pandemic, individuals with symptoms of acute respiratory infection, including minor symptoms such as sore throat or runny nose, should defer routine immunization until they have recovered because they can pose an unnecessary risk to the public and healthcare providers if they have COVID-19. 

# Individuals with suspected, probable or confirmed COVID-19
 Individuals with suspected, probable, or confirmed COVID-19, and those who are close contacts of a case, should not attend scheduled immunization appointments during their period of isolation. Please visit the  updated guidance on discontinuation of isolation specific to your province or territory.  
Post-exposure prophylaxis (PEP) for VPDs
 If PEP with vaccine or antibody products is required (e.g., measles, hepatitis A, hepatitis B, rabies, meningococcus, varicella), it should be given without delay.  If PEP is required for someone with suspected, probable, or confirmed COVID-19, or a close contacts of a case, this should be given without delay using appropriate .
Infants and toddlers
Prioritize primary immunization series: Infants and toddlers without symptoms of acute respiratory infection should continue to receive their routine vaccines on schedule as recommended by their province or territory. While some jurisdictions may defer the 18-month visit based on their COVID-19 epidemiological situation, PHAC suggests that immunizations given at 18 months of age-month still be provided when possible.
Children
 All children who have not completed their primary series and who do not have symptoms of acute respiratory infection should be prioritized for immunization. 
 The 4-6-year boosters can be deferred within this age range. However, the administration should be prioritized before school entry.  School entry may vary depending on the epidemiological situation and pandemic public health measures across the country. 
School-based immunization programs
 Many provinces and territories are currently implementing extended school closures in order to prevent the spread of COVID-19. When school-based immunization programs are restarted, students can either initiate or complete their immunizations at that time. Re-starting a series is never necessary for routine immunization programs. Eligibility criteria should ensure that students who missed immunizations due to COVID-19 school closures remain eligible for the recommended vaccines. 
Adolescent immunizations
 In general, routine adolescent vaccines (e.g. Tdap, HPV, Hepatitis B, MenC-ACYW) can be deferred until full health care services are available, and/or when schools re-open. 
Reminders for Deferred Immunizations
 If doses have been deferred, a reminder, recall, or documentation process should be in place to ensure the child, student or adolescent receives the immunizations when full healthcare and/or school resumes. 
Immunizations during pregnancy
 Prenatal care is critically important, and many prenatal visits will still occur in-person.  NACI currently recommends that Tdap vaccine is provided during every pregnancy, ideally between 27-32 weeks gestation. During the pandemic this should continue during one of the routine in-person prenatal visits or through a public health clinic, pharmacy or family physician office.  If not feasible to combine with another visit, a unique visit would still be justified and recommended during the pandemic.
 NACI currently recommends that influenza vaccine is provided during every pregnancy, at any gestational age. In the fall, influenza vaccine should also be given during pregnancy (see below). 
Adult and older adult immunizations
 Older adults are particularly susceptible to severe outcomes of COVID-19 and are at high risk for VPDs such as invasive pneumococcal disease, influenza, and herpes zoster.  Local COVID-19 community transmission risk should be considered when making the decision to have an older adult come to a clinic only for a immunization during the pandemic.  It would be preferable to offer immunization when it can be combined with another medical visit, and offering multiple vaccines if required, to minimize the risk of acquiring COVID-19 and to reduce the number of health care encounters.   
 For adults over 50 years of age who have received the first dose of recombinant zoster vaccine, the second dose can be deferred until the 6-12 month interval (doses are typically recommended 2-6 months apart, and may be considered up to 12 months apart) assuming that COVID-19 risk will be lower by that time. If an interval longer than 6-12 months after the first dose has elapsed, the vaccine series does not need to be restarted; the decision when to complete the series should take into consideration the local COVID-19 community transmission risk, recognizing that individuals may remain at risk of herpes zoster during a longer than recommended interval between doses 1 and 2.  
Special populations
 Individuals who are immunocompromised, including solid organ and stem cell transplant recipients, and those with chronic conditions, may be particularly susceptible to severe outcomes of COVID-19.  Vulnerable populations should not attend clinics solely for the purpose of immunization in regions with ongoing community transmission of COVID-19.  However, these populations remain priority populations for immunization against VPDs, and jurisdictions should consider alternative strategies to ensure opportunities for immunization in settings where these populations are followed for their medical care.
Immunization of workers
 Immunization of workers in sectors at increased risk of exposure to VPDs (e.g. healthcare workers, laboratory workers) should proceed routinely according to the . 
Travellers
 Those individuals who must  need to be aware of the health risks at their destination as well as any  or required immunizations for entry, and should still be immunized according to recommended schedules. Should a traveller require post-exposure prophylaxis (PEP) following exposure during travel (e.g., rabies PEP, measles PEP), this remains a high priority for care. 
Seasonal influenza programs
 Seasonal influenza presents an ongoing disease burden in Canada during the fall and winter months. Influenza vaccine is the most effective way to prevent influenza illness and influenza-related complications, and will be an important component of managing health care system capacity during the next influenza season in the context of an ongoing COVID-19 pandemic.
Traditional influenza vaccine delivery strategies (e.g., indoor mass immunization clinics) will likely need to be adjusted to incorporate additional infection prevention and control measures to prevent the transmission of COVID-19. It would be preferable to offer immunization when it can be combined with another medical visit, and offering multiple vaccines if required, to minimize the risk of acquiring COVID-19 and reduce the number of health care encounters. Countries in the southern hemisphere (e.g. Australia) are currently exploring alternative influenza vaccine delivery solutions such as outdoor and drive-through vaccine clinics, and their experiences may be instructive for Canada. 
Specific guidance on influenza immunization in the context of COVID-19 will be issued as needed.
Resuming normal immunization activities
 As the pandemic progresses, provinces and territories continue to closely monitor the COVID-19 epidemiological situation.  Vaccine providers should follow advice from their provincial/territorial jurisdiction and the Public Health Agency of Canada on when to relax physical distancing measures and how to resume usual provision of healthcare activities in their local region. At that time, a careful assessment of missed doses will be important to ensure that the pandemic does not leave a long-lasting immunization gap in any Canadian communities.