American Association of Feline Practitioners

Veterinary professionals passionate about the care of cats


When to Test

  • As soon as possible after they are acquired

  • Following exposure to an infected cat or a cat of unknown infection status
  • Prior to vaccination against FeLV or FIV
  • Whenever clinical illness occurs, regardless of previous testing status

Both Viruses Together

  • A single testing protocol is difficult to recommend for all cats.
  • Infected cats may not present with signs of disease.
  • ALL sick cats should be tested.
  • It is not always possible to determine infection status with single test.
  • Repeat tests using different methods may be necessary.


Testing for FeLV: Interpreting Results

  • Results of FeLV testing may be discordant.
  • Abortive infection: negative on the POC test.
  • Progressive infection: positive on the POC test 30+ days after exposure.
  • Regressive infection: negative OR positive on the POC test.
  • PCR testing may be positive in both progressively and regressively infected cats.
  • Other testing results (microwell, IFA, etc.) may be positive depending on stage and class of infection.


Testing for FIV: Interpreting Results

  • A positive POC for FIV test indicates the presence of FIV antibodies.
  • Infected cats will be positive for FIV antibodies 60+ days post-infection.
  • If the patient test is negative, the patient should be retested for FIV in 60 days.
  • Confirmatory testing is ideal and may include a different manufacturer’s POC test, a PCR test, or a Western Blot test.

About FIV Vaccinates

  • FIV vaccine is no longer available in North America since 2015. 
  • Vaccinated cats may retain antibodies against FIV for 7+ years post vaccination.
  • FIV vaccinates may be positive for FIV antibodies.
  • Vaccinated cats may continue antibody positive on some POC tests for 7+ years.
  • Cats testing positive still need to be assessed for previous vaccination.
  • Some POC tests are able to differentiate between antibodies of truly infected versus vaccinated cats. See AAFP Retrovirus Guidelines


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© American Association of Feline Practitioners, 2020