Rabies Serology for Animal Export & FAQS

This information is courtesy of Kansas State Veterinary Diagnostic Laboratory.

How do you measure antibodies to rabies?

Rabies virus neutralizing antibodies are measured using a cell culture method. When antibodies are present in the serum (the clear liquid part of whole blood) of animals or humans, they will prevent rabies virus from infecting cells in culture – this is called neutralizing the virus. The titer or relative concentration of these virus-neutralizing antibodies is measured through specific dilutions of samples added to a standard amount of virus and seeing how many cells get infected. The cells are cultured or grown in incubators for either one or two days depending upon the test method. Both the Rapid Fluorescent Focus Inhibition Test (RFFIT) and the Fluorescent Antibody Virus Neutralization (FAVN) test are methods that measure rabies virus neutralizing antibody titers.c

How long should I wait after my pet has been vaccinated before drawing the sample?

We advise waiting 3-weeks between vaccination and taking a blood sample from your pet to allow them sufficient time to develop an antibody response. However, some countries have different requirements. For example, Sweden requires a 120 day wait period between vaccination and sample draw date. Therefore, we strongly recommend directly contacting regulatory authorities in the country of your destination.

How long does the test take?

Once the sample has been received, the test normally takes about 2-3 weeks to complete. The turn-around time varies according to the demand for testing and holidays. Samples are processed in the order in which they are received. If results are needed on a specific time-line, it is recommended that you contact the laboratory to confirm receipt of the specimen and an estimated time to test result and reporting.

Where is the original FAVN result document?

If the pet is traveling to Hawaii, Guam or any of the Caribbean Islands, the original document has already been sent to the destination.

If the pet is traveling somewhere other than Hawaii, Guam or the Caribbean Islands, we send the original document to the submitting laboratory or clinic. However, if the sample was sent through a reference laboratory (i.e. Antech, Idexx, etc.), the clinic will need to contact the reference laboratory directly to obtain the official FAVN result document. Most destinations will accept a copy of the results. We are available to fax the results directly to government authorities when necessary.

My pet’s rabies titer failed (was <0.5 IU/mL), what’s next?

Most rabies-free countries have extended quarantine periods for pets that don’t meet minimum requirements. Alternatively, the pet can be given another rabies vaccination and have another blood sample submitted. It is best to wait 2-3 weeks after re-vaccination to take a blood sample so that the pet has time to develop a higher antibody response. Please carefully read and interpret the results on the report and contact us if you have questions.

When does the 120 day countdown begin for Hawaii?

The day the sample is received at the K-State Rabies Laboratory begins the countdown. As long as the titer result is at or above the passing level (>0.5 IU/mL) and travel is within 120 days after the received date, the animal will be eligible to enter Hawaii.

Rabies Serology for Vaccine Response

My unvaccinated/overdue pet was bitten by a known/suspected rabid animal. Will a titer test tell me whether my pet has rabies?

Unfortunately, the absence of a titer does not exclude a diagnosis of rabies, since some rabid animals may not have detectable levels of rabies antibodies. Also, the presence of titer may not assure protection from an exposure to rabies. Keep your pet current on its rabies vaccination and contact your veterinarian and local or state health department if you think your pet may have been expose to rabies.

General rabies serology

Does the sample need to be frozen?

No. The sample should be maintained at refrigeration temperature. For shipping, the sample should be sent with coolant packs. Additional shipping instructions are with our submission forms.

Are the results available by the website?

Guardians can search with their animal’s microchip number for the status of the FAVN Test to see if it has been completed but the results cannot be obtained through the internet. The original official FAVN result form is sent to the office of the submitting veterinarian or in some cases to the regulatory authorities where the pet is traveling.