Companion animal vaccinations and informed consent guidance
Vaccination is an essential, cost-effective way of controlling certain important infectious diseases in companion animals. It is performed extensively and is considered relatively low risk.
Vaccination recommendations can be a complex and sometimes controversial issue. However, there are a variety of sources (e.g. Restricted Veterinary Medicine (RVM) Product labels and international guidelines) providing evidence-based information that supports the veterinarians’ decisions.
Adverse events associated with vaccines can happen, although this is rare (Moore et al 2023 1). Veterinarians must therefore consider the risks associated with vaccination, balanced with the significant benefits vaccination provides for the patient and the community it lives in.
Gaining informed consent is important when administering any medicine, including vaccines. Owners who present their pets to be vaccinated should be fully informed by the veterinarian about the purpose, risks, and expected outcomes of each vaccination before they give consent and before the product is administered. Owners must have the opportunity to discuss and raise any questions and concerns. This allows them to make an educated decision about the needs of their pet and fosters a team approach to its care. This team approach can help improve compliance, adherence and strengthen veterinary-client relationships (Spitznagel et al 2; Maddison et al 3).
More information about the process of gaining informed consent and documenting it can be found in the Code of Professional Conduct here, and in Vet Council guidance here.
Immunisation, along with sanitation and clean drinking water (Rodrigues et al 2020 4), is one of the most effective health interventions in the world for saving lives and preventing significant illness
All approved veterinary vaccines used in Aotearoa New Zealand are registered under the Agricultural Compounds and Veterinary Medicines (ACVM) Act and have been assessed for safety and efficacy.
It is important to discuss the most appropriate vaccine and the frequency of administration for the pet. These will be influenced by several considerations that should include species; breed; age; risk of exposure to diseases; timing of the last vaccination; and geographical location.
The cost of an animal vaccination can vary. Factors affecting the cost include the type of vaccine needed and the age and breed of the pet. Some vaccines also require multiple doses to achieve efficacy, which adds to the total cost.
The decision to vaccinate, even with core vaccines, should be based on a risk-benefit assessment for each pet and each vaccine antigen. The benefits of vaccination should be balanced against the risk of adverse events, likelihood of exposure to disease, and disease severity. Every effort should be made to ensure that the pet is healthy before vaccination. However, concurrent illness (including retroviral infections) does not necessarily preclude vaccination5.
An adverse event is defined as any observation in an animal that is unfavourable and unintended following the use of a veterinary medicine. It includes side effects; lack of protection; human exposure; toxicity; or hypersensitivity reactions whether or not the event can be directly attributed to the vaccine. Most adverse reactions are mild, transient and self-limiting. The most severe forms of adverse reactions are very rare, such as injection site tumours, anaphylaxis and autoimmune dysfunction.
We occasionally hear from veterinarians who are concerned that some recommendations from guidelines contradict information in product leaflets or datasheets. Some worry that if they adopt guideline recommendations they might be criticised. For example, if they revaccinate adult animals less frequently than suggested in the product leaflet, or if they give additional doses of vaccine to animals between 12 and 20 weeks of age.
This is not usually the case. Selecting the most appropriate vaccine and how often it’s administered depends on the considerations listed earlier in this guidance, such as age and breed and may include other context specific aspects. Veterinarians are expected to use their professional judgement, as well as current knowledge and guidance (based on scientific evidence), when selecting an appropriate vaccination regime. The WSAVA Vaccination Guidelines 6 and the NZVA vaccination guidelines 7 provide useful advice on vaccinations for cats and dogs.
It is essential for pet owners to understand the importance of animal vaccination in preventing diseases. Not only does vaccination protect the health and wellbeing of their animals, but it also contributes to public health by reducing the spread of contagious diseases between animals.
Addressing common misconceptions about animal vaccination is an important part of educating pet owners. Some people may have concerns about the safety and effectiveness of vaccines, so it is essential to provide accurate information and evidence-based facts to address these concerns.
Encouraging responsible vaccination practices involves promoting regular check-ups with veterinarians and following recommended vaccine schedules for pets. This includes ensuring that pets receive their core vaccinations as well as any additional vaccines based on their lifestyle, environment, and potential exposure to specific diseases.
The product leaflet/data sheet is a legal document that forms part of the ACVM product registration package for a vaccine. This document provides details about the safety and efficacy of the product and states the minimum Duration of Immunity (DOI) that can be expected after appropriate vaccination administration.
Guidelines are based on all available evidence about DOI by vaccines for cats and dogs, not just the minimum data generated by manufacturers.
Some New Zealand guidelines may recommend vaccinating every three years or less with core vaccine products, even if it has a one-year DOI claim in some countries. Although the advice from guidelines sometimes differs from information in the product leaflet, veterinarians can generally use a vaccine according to recognised guidelines (and therefore the most current scientific evidence) by obtaining informed owner consent for administration that may vary from the product’s registered use (i.e. “off-label use”).
At the time of vaccination, the following information should be recorded in the patient’s 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
· Anatomical site and route of vaccine administration.
Any adverse events should be recorded in a way that will alert practice staff during future visits, such as using popups in the patient management platform.
Informed consent must be documented in the patient’s medical record to show relevant information was provided to the client and that they consented to the procedure (for both on-label and/or off-label use of vaccines). At the very least, the note in the clinical record should indicate that a discussion about risks and benefits took place before the vaccination.
1 Moore GE, Morrison J, Saito EK, Spofford N, Yang M. Breed, smaller weight, and multiple injections are associated with increased adverse event reports within three days following canine vaccine administration. J Am Vet Med Assoc. 2023 Jul 14;261(11):1653-1659. doi: 10.2460/javma.23.03.0181. PMID: 37451674.
2 Spitznagel MB, Carlson MD. Caregiver Burden and Veterinary Client Well-Being. Vet Clin North Am Small Anim Pract. 2019 May;49(3):431-444. doi: 10.1016/j.cvsm.2019.01.008. Epub 2019 Mar 4. PMID: 30846380.
3 Maddison, Jill & Cannon, Martha & Davies, Rebecca & Farquhar, Robyn & Faulkner, Brian & Furtado, Tamzin & Harvey, Gareth & Leathers, Fiona & Snowden, Austyn & Wright, Ian. (2021). Owner compliance in veterinary practice: recommendations from a roundtable discussion. Companion Animal. 26. S1-S12. 10.12968/coan.2021.0029.
5 2020 AAHA/AAFP Feline Vaccination Guidelines
6 2024 guidelines for the vaccination of dogs and cats – compiled by the Vaccination Guidelines Group (VGG) of the World Small Animal Veterinary Association (WSAVA)
7 NZVA MTN: Vaccine use in New Zealand cats and dogs