FIV Vaccine Recommendations

FIV or feline immunodeficiency virus is a retrovirus that affects the immune system of cats. Once infected, the immune system isn't capable of fighting bacteria and other infections. Cats contract FIV from infected cats through direct contact with the saliva during cat fights that result in bites or wounds. Cats suffering from FIV are more susceptible to illnesses such as lymphoma, respiratory diseases, gastrointestinal disorders, neurological disorders and skin infections. FIV positive cats can survive for several years and become carriers of the disease. In order to prevent the spread of diseases to other pets, a vaccine for FIV is now available. Although it doesn't provide total resistance to the disease, it provides a certain amount of protection.

Vaccine Recommendations:

  • Cats that roam outdoors frequently and come in contact with other cats.
  • Cats that are housed with a FIV positive pet.
  • Cats that are known to get into fights.
  • Cats that live in close proximity to FIV positive pets in the neighborhood.

Administration of the FIV Vaccine

The vaccine should be given to all pet's that are at risk of contracting FIV. The vet will first perform an FIV test to check if the cat is FIV positive or negative. The vaccine is given to pets in a series of 3 shots at intervals of 3 weeks. Once vaccinated, pets will test positive for FIV due to the presence of antibodies. Pet owners that prefer to vaccinate cats have to administer the vaccines at the scheduled time in order to prevent any risks.

Concerns Regarding the FIV Vaccine

Although the vaccine is recommended for cats in the high risk group, the effectiveness of the vaccine is not 100 percent and pets that are tested for FIV after vaccination will always test positive. This matter is of great concern to pet owners as lost cats that are found FIV positive are euthanized. In addition, diagnostic tests that are performed before vaccination also reveal several false negatives particularly when tested with PCR tests. Studies also reveal that kittens test positive for FIV if they obtain antibodies from an infected queen (mother). However, kittens that test positive should be retested at intervals in order to confirm if they are really FIV positive.

Vaccine Associated Sarcoma

Apart from questions concerning the tests for FIV and its vaccine, pet's that receive the vaccine are susceptible to vaccine associated sarcoma (VAS). The FIV vaccine is a killed vaccine that contains adjuvants. These adjuvants increase the risk of developing granulomas, skin lesions and malignant tumors. Cats that develop VAS have to be treated with surgical extraction of the tumor and radiation therapy.

Efficacy of the Vaccine

Although the risk factors of vaccinating pets for FIV are controversial, laboratory studies show a high percentage of efficacy in those cats that are vaccinated in comparison with control groups of unvaccinated pets. Since FIV manifests itself in 5 subtypes, it's important to determine the subtype of FIV in infected cats and perform re-tests to rule out false positives.

Pet owners should discuss with the vet, the best approach to protect their pet's from FIV. The vaccine is a non-core vaccine and is useful particularly for pet's that roam outdoors.