FeLV & FIV


FeLV & FIV
FeLV/FIV Testing

CATS-R-US.org does not routinely test cats or kittens for feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) prior to adoption. FeLV and FIV are uncommon viruses that can be transmitted between felines. FeLV and FIV testing will be limited to cats or kittens with health concerns that are associated with FeLV and FIV, cats with known exposure, or if otherwise recommended by a veterinarian. The decision to not routine test for FeLV and FIV has been made for several reasons:
  • A very small percentage of cats are affected by these diseases. In the United States, 2.3-2.5 % of the total cat population is affected by each disease. In the United States, there are an estimated 30-40 million community cats living in feral colonies, the streets or wooded areas and 90 million companion cats living in human households.
  • Cats who were recently exposed to FeLV or FIV may incorrectly test negative (false negatives). Any cat with recent exposure will test negative,  giving a false sense of security. This occurs because the virus or the cat’s immune response has not had time to develop to a level that can be detected by the test. Many rescue cats have an unknown or incomplete background that could involve recent exposure to FeLV or FIV, including stray cats, indoor-outdoor cats, or multi-cat households. 
  • Cats who have been vaccinated against FIV or FeLV may test positive although they do not have either disease.
This policy will allow us to make more informed medical decisions for each cat and kitten based on new guidance from the American Association of Feline Practitioners. Adopters are encouraged to follow up with their veterinarian for an initial wellness visit and to determine care for their newly adopted cat. We advise adopters to keep existing cats separated from newly adopted cats until they are seen for their first wellness visit. We also recommend that any cats or kittens who are symptomatic or may have been exposed to FeLV or FIV already in the adopter’s home are tested prior to introducing the cat or kitten,.

WHAT IS FELV AND FIV?

Both FeLV and FIV are contagious, viral diseases that affect cats only. Although there are some similarities between the two diseases, each has its own distinct characteristics. FIV is primarily transmitted by bite wounds. Other methods of infection, such as queen-to-kitten or sexual transmission, are possible but unlikely. FIV positive cats living in stable households (i.e. households without cats fighting) with FIV negative cats are unlikely to transmit this disease. Once a cat is infected with FIV, the virus makes DNA copies of itself that are inserted into cat’s own genetic material. Following this primary stage, most cats remain asymptomatic for years. Eventually, the immune system becomes progressively dysfunctional and predisposes the cat to infection by other diseases. There is no cure for FIV. Survival time varies but FIV positive cats often live long, healthy lives.

FeLV is most commonly transmitted from an infected queen (mother cat) to her kittens and between cats living closely in the same environment. FeLV may be transmitted in saliva, milk, urine, and feces. Once infected, the cat’s immune system can respond in a few different ways. Some cats that are initially exposed to the virus can eliminate the infection. Others can control the infection, preventing illness for some time. Another set of cats will become what’s referred to as “progressively” infected, meaning their immune system cannot fend off the virus. These cats may develop significant health problems and a shortened life span.

WHAT SYMPTOMS ARE ASSOCIATED WITH DISEASES?

Some of the main symptoms associated with FeLV and FIV include delayed healing from infections (including wounds and upper respiratory infections), diarrhea, neurologic disease, weight loss, and severe gingivitis. It is important to keep in mind that several other diseases can also cause these symptoms so the presence of one or more of these symptoms does not automatically mean that your cat has FeLV or FIV.

IS THERE A CURE FOR FELV OR FIV?

Currently, there is no cure for either disease. With FeLV, some cats may naturally clear infection in the early stages of disease. Treatment is aimed at maintaining an otherwise healthy cat and addressing symptoms associated with the diseases, such as dental disease and delayed healing from wounds, early. A good, nutritional diet, keeping your cat indoors, and taking your cat for regular veterinary exams are essential to promoting a strong immune system, prevention of secondary illness, and catching any signs of illness early on.

SINCE MY NEW CAT MAY NOT BE TESTED PRIOR TO ADOPTION, WHAT SHOULD I DO NEXT?

We recommend that you establish a relationship with a veterinarian to determine the best testing strategy. Due to the complexity of diagnosis and limitations of point-in-time testing, more than one test may be required to determine a cat’s disease status. Until this testing is performed, we recommend keeping your newly adopted cat separate from your resident cats.

WHAT ABOUT CATS IN FOSTER HOMES? WILL OUR FOSTERS’ RESIDENT CATS BE AT RISK? 

For both FeLV and FIV, the risk of transmission between adult cats is very low unless crowding or immunosuppression is present. There is a small possibility that a kitten would transmit FIV or FeLV to an adult cat. If foster parents are concerned, they may consider separating foster cats from their resident cats and use normal hand washing techniques.

SHOULD I ADD AN FELV OR FIV POSITIVE CAT TO MY HOUSEHOLD?

Many FeLV and FIV cats can have happy, healthy lives for many years. We recommend that all FeLV and FIV positive cats receive routine preventative veterinary care, including annual exams. Your veterinarian may provide additional recommendations to optimize your cat’s health, including dental care and routine blood work.
If you already have cats in your household, there is a risk that your resident cats could become infected with the disease. For both FeLV and FIV, the risk of transmission between adult cats is low unless crowding or immunosuppression is present. Cats develop age-related immunity to FeLV in particular and published studies demonstrated that there was no spread of FIV between cats when housed together in a rescue home over a period of months to years. However, FeLV positive cats do carry some risk of transmitting the disease to other cats, especially if any other cats in the household have underlying disease, are very old or very young.

CAN I GET FELV OR FIV FROM MY CAT?

No, fortunately neither of these diseases can be transmitted to humans, dogs, or other species.

WHERE CAN I GET ADDITIONAL INFORMATION ON THESE DISEASES?

Your primary care veterinarian is an excellent resource on this topic and can help you develop a personalized health plan for your cat(s). Here are links to more detailed information on FeLV and FIV:
  • https://catfriendly.com/feline-diseases/felv/
  • https://catfriendly.com/feline-diseases/fiv/