How can post-vaccinal serological screening verify the success of the initial puppy or kitten immunization series?

The AAHA and World Small Animal Veterinary Association (WSAVA) recommend that puppies receive core vaccines, first at six to eight weeks of age, then every two to four weeks until 16 weeks of age or older. This is traditionally followed by a booster, either at 12 months of age or 12 months after completion of the puppy series.

The rationale for the booster is that it will result in a proper adaptive immune response in puppies whose humoral adaptive immune response is still absent or incomplete. Potential reasons listed in the current WSAVA guidelines are residual maternal antibody, inadequate antigenicity of vaccine components or the failure of the animal’s immune system to respond to one or more core vaccines.

A vulnerability of this approach is that it can leave a puppy inadequately protected for an extended period of time if there were an inadequate response to the puppy shots. Therefore, it would be reassuring to both owners and veterinarians to verify that a puppy properly responded to the series of three to four core vaccine shots by testing the serum antibody levels four weeks after completion of the “puppy shot” series. This would typically be around 20 weeks of age.

An overview of this approach and the decision making associated with it is presented in the WSAVA’s “Guidelines for the Vaccination of Dogs and Cats.”

How does post-vaccination serological screening help with the decision to revaccinate?

Regarding viral vaccines, current practice often combines clinical judgment and client wishes to determine the need for additional serological viral screening between vaccinations. The MSU VDL offers screening of titers against viral vaccine components to assist with these re-vaccination decisions.

In Michigan and many regions, the prevalence of canine leptospirosis warrants consideration of routine leptospiral vaccination. In contrast to the long duration of immunity for the core viral vaccines, the duration of protective immunity for leptospirosis vaccines is less clear and there is little information in the literature to assist with the decision of how frequently to vaccinate. In addition, owners and veterinarians remain concerned regarding potential for adverse reactions associated with use of leptospiral vaccines.

Therefore, veterinarians request advice regarding the frequency of vaccination in order to balance the risks of leptospiral vaccination with the clinical benefits of protection. As a unique service, the MSU VDL offers screening of leptospirosis titers to assist veterinarians in making the decision to revaccinate for leptospirosis. MSU VDL scientists have performed vaccination/infection trials in puppies to support our recommendations and an individual interpretation for each animal is provided.

What testing formats are available?

The MSU VDL offers vaccine serology screens for both dogs and cats. Serum (2 mL) is requested for these tests and this testing can be done in combination with other tests sent to the laboratory, e.g. thyroid function tests.

Our Service

The MSU VDL offers a full range of testing for vaccine-induced antibodies and offers unique services in the interpretation of leptospirosis vaccine titers.

Canine Vaccine Antibody Panel (80101) includes:

  • Canine Distemper Virus (CDV) VN (80050)
  • Canine Adenovirus-2 (CAV-2) VN (80047)
  • Canine Parvovirus-2 (CPV-2) HI (80054)

Canine Vaccine Panel + Lepto (95996) includes the above plus Leptospirosis (95055).

Revaccination is recommended for dogs with a CDV titer below 32, a CPV-2 titer below 80, and a CAV-2 titer below 16. An interpretation of the leptospirosis titers is provided based on challenge data in vaccinated dogs.

Feline Vaccine Screen (80102) includes:

  • Feline Herpesvirus-1 (FHV-1) VN (80031)
  • Feline Calicivirus (FCV) VN (80066)
  • Feline Panleukopenia Virus (FPV) HI (80035)

We recommend revaccination for cats with an FHV-1 titer below 16, an FCV titer below 32, and an FPV titer below 40.

Collecting and Submitting Samples

Details regarding turnaround time, collection protocol, and requirements for specimens and shipping are available for each test in our catalog. For samples that need to be kept cold during shipment, we recommend using an MSU VDL insulated mailer with pre-paid overnight UPS delivery.

For more information, please contact the Virology Laboratory at 517.353.1683.