Pet parents often ask me whether their dog needs to continue to receive booster vaccinations throughout their senior years. Vaccinations help pets build natural antibodies to specific viral and bacterial invaders, so they protect pets from the severe illnesses these bugs can cause. When we vaccinate our pets, we can also help protect others’ pets from illness by reducing disease spread. In some cases antibodies protect pets for many years! In other cases antibodies dwindle, so their protection lasts for only a short time. This is why pets need some vaccination boosters sooner than others.
So my short answer to this question is usually yes—most senior dogs still need vaccinations! Whether your senior dog can skip vaccinations depends on the type of vaccination and your dog’s health status, lifestyle, risk of becoming infected, and antibody level.
Checking antibody levels before vaccination
Titers are blood tests that measure antibodies to infectious bugs or other harmful agents. Your veterinarian can use these tests to check your dog’s immunity to canine distemper virus, parvovirus, and adenovirus, which dogs are routinely vaccinated against. The results help your veterinarian determine whether your dog needs these booster vaccinations. You can ask your veterinarian about the pros and cons of titer testing for your dog and the costs. Titer tests are most often used for dogs who have:
- a history of a serious allergic reaction to vaccination,
- immunocompromise related to illness or immunosuppressive therapy,
- a history of poor response to vaccination (for example, getting sick with parvovirus despite being fully vaccinated against it),
- an unknown vaccination history, or
- pet parents who are hesitant about vaccinating their dog.
If the titer results indicate that your dog has sufficient antibodies to canine distemper, parvovirus, and adenovirus, your pet may not need those boosters. If the results show that your dog's antibodies are low, your dog’s immune system is unlikely to protect against those infections, so boosters are probably needed. In any case, your veterinarian will evaluate your dog's risk factors for infection and suggest the best vaccination plan.
If your dog's titer results show that your dog has sufficient antibodies to canine distemper, parvovirus, and adenovirus and you decided to forgo those booster vaccinations, your groomer, boarding facility, or landlord may still require proof of current vaccination. In that case, ask your veterinarian to provide an exemption letter or waiver that states your dog is not due for those vaccinations based on their health status. Even with an exemption letter, your dog may be considered as not current on their vaccinations and be refused access to some facilities.
Titer test limitations
Titer test results can’t help us check for protection against every type of infection or insult. For example, the results don’t tell us whether a pet has sufficient immunity to protect against leptospirosis, canine influenza, kennel cough, Lyme disease, or rattlesnake venom. But vaccinations against these agents are not routinely given unless dogs have an increased risk of exposure. Your veterinarian can recommend whether your dog should receive these vaccinations based on your dog’s lifestyle and geographic location.
Keep in mind that titer test results don’t give a 100% guarantee that your dog’s antibodies will (or won’t) protect against illness, and vaccinations may still be required for certain types of activities such as boarding or for travel.
Rules regarding rabies
Rabies vaccinations for pets and given at specific intervals are required by law because rabies is a highly fatal virus to people and other animals. Infected mammals can transmit it through their saliva, and people usually become infected by having close contact with or being bitten by a rabid animal. So even if you ask your veterinarian to run a titer test for rabies antibodies and your pet’s result indicates adequate immunity, this result alone is not an accepted reason for exemption from rabies vaccination or booster in any state.
A few states allow rabies vaccination exemption only if vaccination poses a serious health threat to the pet (note: senior age alone is not typically considered a sufficiently serious health threat), but most states do not allow a health threat exemption. And each state’s laws differ, so dogs who do have rabies vaccination exemptions may not be allowed to have contact with other animals in some settings, such as at boarding facilities or dog parks.
Also be aware that if your dog has been exempted from rabies vaccination but has potentially been exposed to rabies or has bitten someone, your dog will still be subject to the same rules for rabies quarantine, observation, and revaccination that apply to unvaccinated dogs.
More about caring for your older pup:
"it's Never Long Enough: A practicle guide to caring for your geriatric dog"
Geriatric Dog Health & Care Journal
References and suggested reading
American Animal Hospital Association. Rabies vaccinations: titers, exemptions, and protocols. American Animal Hospital Association. Accessed January 28, 2022.
American Animal Hospital Association. Top 10 things you need to know about AAHA’s Canine Vaccination Guidelines. Accessed January 31, 2022. https://www.aaha.org/aaha-guidelines/vaccination-canine-configuration/resources/top-10-things-you-need-to-know/
Burns K. To titer or to revaccinate. American Veterinary Medical Association. June 15, 2016. Accessed January 28, 2022. https://www.avma.org/javma-news/2016-07-01/titer-or-revaccinate
Nelson SC, Moore SM. Dog and cat vaccines and titer testing. Kansas State University Diagnostic Laboratory. Accessed January 31, 2022. https://ksvdl.org/laboratories/rabies-laboratory/dog-cat-vaccines-titer-testing.html