• Chappelle Small Animal Hospital: Fort Collins Vet Services


Client Education Articles

Feline Leukemia Virus and Feline Immunodeficiency Virus

What are they?

Feline Leukemia Virus (FELV) and Feline Immunodeficiency Virus (FIV) are viruses that affect cats.  Both of these viruses can cause immunosuppression in cats, which means that their immune systems don’t work as well as they should. This can lead to other infections, some of which can be life threatening.

How are FELV and FIV transmitted?

FELV is often referred to as the “friendly cat disease.” It can be transmitted through prolonged casual exposure to infected cats. Types of exposure can include grooming, sharing food dishes, and urine/fecal contamination. FIV is often called the “fighting cat disease” as it is mostly transmitted through infected cat bite wounds. Both of these diseases can be passed from the mother to the kittens.

What tests are needed?

Simple blood tests can be used to find out the FELV/FIV status of cats and kittens. It is recommended that all kittens be tested for both FIV and FELV at their initial examination with your veterinarian. Older cats may also be tested depending on their lifestyle and risk factors. It is also common to test for these diseases in sick cats.

How are FELV and FIV prevented?

FELV can be prevented by the use of vaccinations. It is recommended that all kittens receive the FELV vaccination series, regardless of whether they will be indoor or outdoor cats. FIV vaccines are not used as much, particularly due to the fact that current tests cannot discriminate between infected and vaccinated cats. 

To determine the best vaccination protocol, discuss your cat’s lifestyle and potential risk factors with your veterinarian. Together, you can come up with a vaccination protocol, as well as potential lifestyle changes, that will protect your cat against these serious diseases.