Feline Leukemia (FeLV) Information

Feline Leukemia Virus (FeLV), is a virus that attacks the immune system of a cat. It isn't a form of cancer, but is a virus that weakens the immune system. FeLV can cause a variety of diseases in addition to leukemia. Like all viruses, FeLV is a tiny microorganism that can only replicate itself inside living cells. FeLV is specific to members of the cat family and does not pose a risk to other species of animals or people.

How common is FeLV?

The FeLV infection is found worldwide. In general, around 1-2% of the cat population is persistently infected with this virus, and many more are exposed.

How is FeLV transmitted?

Direct contact between cats is the most frequent method of FeLV infection. The virus is fragile and cannot survive longer than a few hours outside of the cat. A cat with FeLV sheds a large quantity of the virus in its saliva, as well as in other bodily fluids such as nasal secretions, urine and feces. However, FeLV is not a highly contagious virus, and transmission generally requires a prolonged period of close contact between infected and susceptible cats. Close contact activities include mating, mutual grooming, and sharing of litter trays and food bowls. Cat bites by an infected cat can readily transmit infection.

Is FeLV contagious?

FeLv is only contagious to other cats. For this reason we require adopters to keep their FeLV+ cats indoors only. FeLV+ cats should only cohabitate with other FeLV+ cats as the virus is spread from cat to cat via saliva (sharing food bowls, grooming each other, etc.), urine, blood, and from mother cat to kittens during pregnancy. Feline leukemia is species specific so other animals such as dogs cannot contract the virus. The virus itself is not airborne and dies rapidly in the environment so you won't have to worry about carrying the virus on clothes when you leave the house or have friends over.

How is FeLV diagnosed?

The screening for FeLV is generally an ELISA snap test (often in combination with the feline immunodeficiency [FIV] test). All KHS cats available for adoption were tested for FeLV via this method. False positives do occasionally occur with these tests, so adopters may retest the cat at a later date or submit blood via their personal veterinarian for further laboratory diagnostics. Cats older than 1 year of age who test negative tend to remain negative, even with exposure, due to natural resistance to infection at that age.

Are the FeLV+ cats available for adoption sick?

No, The FeLV+ cats KHS has available for adoption are not displaying any signs of illness from this virus. But because their immune systems are suppressed, they have an increased risk of getting sick. This makes protecting them from stress, feeding a high quality diet, taking them to the vet regularly, and addressing health problems as soon as they arise is absolutely critical. You wouldn't know a cat had FeLV by just looking at it, and many people have FeLV+ cats in their home and don't even know it because they have never had them tested.

Do FeLV+ cats need special medication or care?

No, not while they are healthy. When they do eventually get sick they will usually become sick very quickly and may need more care than a normal cat as their immune system does not work as well. Some vet clinics recommend keeping FeLV+ cats on anti-viral drugs to help keep the virus from replicating. We recommend checking with your personal veterinarian regarding preventative measures for these cats.

Is there any treatment for FeLV infection or disease?

There is currently no specific treatment for FeLV-infected cats. There is no treatment to eliminate the virus from the body. Most FeLV-infected cats will eventually die or require humane euthanasia due to diseases related to their infection. However, many cats showing FeLV-related disease will improve with symptomatic treatment, at least temporarily. For example, if FeLV is causing immunosuppression and the patient develops secondary infections, the secondary infections may be treatable, leading to clinical improvement.

Can FeLV-positive cats have a good life?

FeLV-positive cats can live perfectly happy lives. People who have FeLV-positive cats just need to be aware that those cats may usually have a shorter life span and that they should be taken to a veterinarian as soon as a problem is noticed. Many people who adopt and care for FeLV-positive cats describe it as a positive, deeply rewarding experience, and that they would gladly do so again.

Why do you hear such a negative stigma regarding Feline Leukemia?

There are many myths out there about feline leukemia. As a result, it is often difficult to find people willing to adopt or foster FeLV+ cats. However, the Kentucky Humane Society knows that Feline Leukemia is a very manageable virus and with the proper routine care, these cats can live normal lives for prolonged periods of time. We know that these cats are a population at risk in other shelters and we believe we can make a difference in their lives by placing them in loving homes that view them as furever family members.

I'm still not sure. Can you give me more information?

Yes, we would be more than happy to talk to you about the FeLV+ cats at KHS and about the disease. If you would like more information, please email foster@kyhumane.org and let them know you are interested in more information on FeLV+ cats.

Post Adoption

After you adopt a Feline Leukemia positive cat, we recommend you schedule an appointment with you regular veterinarian to establish a relationship with your new kitty. Your veterinarian can recommend any preventative measures they feel your new family member would benefit from. If you do not have a veterinarian that you currently see, we have included a list of local veterinarians on the next page who are familiar with Feline Leukemia.

What medical issues should I look for post-adoption?

Moving into a new home can be stressful for cats since they thrive on familiarity and consistency. Be aware that cats are generally very skilled at hiding their pain and discomfort. Prolonged stress can, in turn, lead to illness. If you adopt a FeLV+ cat, it’s important to be aware of the symptoms of common stress-related illnesses that can appear post-adoption.

Local Resources (Louisville Area)

The following list includes a few local veterinarians who have experience treating and caring for cats with Feline Leukemia.

Stony Brook Animal Hospital

Dr. Kimberly Siegwald

4600 Taylorsville Rd

Louisville, KY 40220

(502) 491-9096

Banfield Louisville SW

Dr. Stephanie Siegwald

4601 Outer Loop

Louisville, KY 40219

(502) 969-3066 

Shively Animal Clinic & Hospital PSC

2401 Dixie Hwy

Louisville, KY 40216

(502) 778-8317

VCA Fairleigh Animal Hospital

1212 Bardstown Road

Louisville, KY 40204

(502) 451-6655

VCA Shelden Animal Hospital

6017 Bardstown Road

Louisville, KY 40291

(502) 384-6888

Lyndon Animal Clinic

1000 Lyndon Lane

Louisville, KY 40222

(502) 425-5834