Position Statements

Vaccination of Animals

May 1, 2019

Position

The Canadian Veterinary Medical Association (CVMA) supports the use of vaccines by veterinarians to control and prevent infectious disease in animals, including domestic animals, poultry, fish and wildlife. Vaccine protocols including antigen selection and revaccination intervals should be individualized at the animal or group level as part of a comprehensive veterinarian-supervised preventative health care plan.

Summary

  • Vaccines play an important role in supporting the health and welfare of both animals and humans.
  • Vaccines registered for use in Canada have been tested for safety and efficacy, and can be administered with confidence when used in accordance with label instructions and veterinary advice.
  • The vaccination needs of every patient or group of patients should be assessed regularly by a veterinarian as part of a comprehensive preventative health care strategy.
  • Adverse effects, if any, should be reported.

Background

  1. Vaccines have an important role in animal and human health (1,2) by:
    • protecting animals from infectious diseases;
    • protecting human health in the case of vaccinating animals for zoonotic diseases (e.g., rabies, leptospirosis);
    • contributing to animal health and welfare by helping to control disease, and thereby reducing disease suffering and mortality;
    • helping to reduce the need for antimicrobials and associated risks from the development of antimicrobial resistance (3);
    • controlling disease in wildlife populations including baiting with approved wildlife vaccines (4).

  2. In Canada, veterinary biologics, including vaccines, are regulated by the Canadian Food Inspection Agency (CFIA). Vaccines licensed for use in Canada have been tested for purity, potency, safety and efficacy when used in the target species according to the manufacturer's label recommendations (5).
  3. In addition, autogenous biologics may be developed and used under certain regulatory criteria. Such vaccines play an important role in food animal medicine for emerging or other diseases, and may be exempted from efficacy requirements.  They may be used in certain cases when a licensed vaccine is not effective or is not available. Autogenous vaccines are produced in approved licensed facilities, and are used under the supervision of a veterinarian (6).
  4. In all cases, vaccine manufacturers’ instructions should be carefully followed. The required labeled dosage of a particular vaccine is the volume of that vaccine that has been determined to be necessary to produce an adequate and protective immune response in the patient, and should not be adjusted based on the size or weight of the patient.
  5. The vaccination needs of every patient or group of patients should be assessed regularly by a veterinarian as part of a comprehensive preventative health care strategy. The decision to administer a particular vaccine should be based on a risk assessment that considers the likelihood of exposure to a disease agent, transmissibility of disease in question, the health status on the patient(s); severity of the disease and human health risks; and other relevant factors (7).
  6. Veterinarians should exercise their best professional judgment on a case-by-case basis when designing and implementing vaccination protocols, including evaluating the need for vaccination by applying current scientific information on infectious diseases. Vaccination protocols may vary depending on the age, breed, health status of animals, environmental factors, lifestyle of owners and animals, travel, regional variation in disease prevalence of agents present in a given geographic area, susceptibility of the patient(s), etc. (7-10).
  7. Measurement of serum antibody titres may provide baseline information to monitor immunity, and help veterinarians in advising their clients about certain vaccination decisions. Titres may not always be predictive of an individual patient’s immune status, and results may vary among tests and between laboratories. Veterinarians should remain cautious in interpreting serological data, with respect to minimum protective titres (4).
  8. The CVMA acknowledges that the use of vaccines is associated with certain risks, including adverse reactions. Most adverse reactions are transient, mild, and occur infrequently. However, more serious adverse events can occur such as sarcomas (12), or a reaction to the vaccine itself (13). Veterinarians should make clients aware of both the potential risks, as well as the benefits of vaccination.
  9. It is strongly recommended that veterinarians report adverse events using established protocols in order to provide regulators, manufacturers, and the veterinary community with the best possible information on vaccine safety (14).
  10. The CVMA supports surveillance for infectious diseases to provide veterinarians with the best information available to make informed decisions regarding vaccination protocols within a preventative health care plan.

References

  1. Roth J. Veterinary Vaccines and Their Importance to Animal Health and Public Health. Procedia in Vaccinology 2011;5:127-136, Available from: https://www.sciencedirect.com/science/article/pii/S1877282X11000270  Last accessed August 24, 2018.
  2. Monath T. Vaccines against diseases transmitted from animals to humans: A one Health Paradigm. Vaccine 2013;31:5321-5338. Available from: https://doi.org/10.1016/j.vaccine.2013.09.029  Last accessed August 24, 2018.
  3. Vallat B. Vaccination as a tool to reduce antimicrobial resistance worldwide Engineering Conferences International ECI Digital Archives Vaccine Technology VI Proceedings 6-16-2016; Available from: http://dc.engconfintl.org/cgi/viewcontent.cgi?article=1033&context=vaccine_vi  Last accessed August 24, 2018.
  4. Rabies in wildlife. Government of Ontario. Available from: https://www.ontario.ca/page/rabies-wildlife#section-4  Last accessed August 24, 2018.
  5. Canadian Food Inspection Agency. Veterinary Biologics. Available from: http://www.inspection.gc.ca/animals/veterinary-biologics/licensed-products/eng/1305488042307/1320704013875  Last accessed February 25, 2019.
  6. Guidelines for Use of Autogenous-Biologics. AVMA. Available from: https://www.avma.org/KB/Policies/Pages/Guidelines-for-Use-of-Autogenous-Biologics.aspx  Last accessed August 24, 2018.
  7. Vaccination Principles. AVMA 2018. Available from: https://www.avma.org/KB/Policies/Pages/Vaccination-Principles.aspx  Last accessed August 24, 2018.
  8. Development of New Canine and Feline Preventive Healthcare Guidelines Designed to Improve Pet Health. J Am Animal Hospital Assoc 2011;47:306-311. Available from: https://www.aaha.org/public_documents/professional/guidelines/aaha-avma_preventivehealthcareguidelines.pdf  Last accessed August 24, 2018.
  9. Vaccinations. Available from: http://www.cathealthy.ca/wp-content/uploads/2014/07/CatHealthyProtocols_6.pdf  Last accessed August 24, 2018.
  10. AAHA Canine Vaccination Guidelines 2018. Available from: https://www.aaha.org/guidelines/canine_vaccination_guidelines.aspx  Last accessed August 24, 2018.
  11. To titer or to revaccinate. JAVMA News 2016. Available from: https://www.avma.org/News/JAVMANews/Pages/160701a.aspx  Last accessed August 24, 2018.
  12. Hartmann K, Day MJ, Thiry E, Lloret A, Frymus T, Addie D, et al. Feline injection-site sarcoma: ABCD guidelines on prevention and management. J Feline Med Surg 2015;17:606-13. Available from: https://www.ncbi.nlm.nih.gov/pubmed/26101312 Last accessed February 25, 2019.
  13. Valli JL. Suspected adverse reactions to vaccination in Canadian dogs and cats. Can Vet J 2015;56:1090-1092. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4572830/  Last accessed August 24, 2018.
  14. Canadian Food Inspection Agency. Veterinary Biologics Guideline 3.15E: Guideline for Reporting Suspected Adverse Events Related to Veterinary Biologics. Available from: http://www.inspection.gc.ca/animals/veterinary-biologics/guidelines-forms/3-15e/eng/1328599858279/1328600476085  Last accessed August 24, 2018.