What is Feline Leukemia?

A Manageable Disease!

Feline leukemia virus (FeLV) is a retrovirus, so named because of the way it behaves within infected cells. All retroviruses, including feline immunodeficiency virus (FIV) and human immunodeficiency virus (HIV), produce an enzyme, reverse transcriptase, which permits them to insert copies of their own genetic material into that of the cells they have infected.

How common is the infection?

In the United States, approximately 2 to 3% of all cats are infected with FeLV. Rates rise significantly 13% or more in cats that are ill or very young. (In the last decade these numbers have been on the decline thanks to more cats staying inside, spay/neutered or vaccinated.)

How is FeLV spread?

Cats persistently infected with FeLV serve as sources of infection. Virus is shed in very high quantities in saliva and nasal secretions, but also in urine, feces, and milk from infected cats. Cat-to-cat transfer of virus may occur from a bite wound, during mutual grooming, and (though rarely) through the shared use of litter boxes and feeding dishes. FeLV doesn't survive long outside a cat's body - probably less than a few hours under normal household conditions.

What cats are at greatest risk of infection?

Cats at greatest risk of infection are those that may be exposed to infected cats, either via prolonged close contact or through bite wounds. Such cats include:

Cats living with infected cats or with cats of unknown infection status
Cats allowed outdoors unsupervised, where they may be bitten by an infected cat
Kittens born to infected mothers

Kittens are very susceptible to infection but as they grow older, most cats develop an increasing resistance to FeLV infection.

What does FeLV do to a cat?

Feline leukemia virus is the most common cause of cancer in cats, it may cause various blood disorders, and it may lead to a state of immune deficiency that hinders the cat's ability to protect itself against other infections. Secondary infections are responsible for many of the diseases associated with FeLV.

What are the signs of disease caused by FeLV?

During the early stages of infection, it is common for cats to exhibit no signs of disease at all. However, over time, the cat's health may progressively deteriorate or be characterized by recurrent illness interspersed with periods of relative health. Signs can include:

Loss of appetite	Persistent fever
Poor coat condition	Persistent Diarrhea
Enlarged lymph nodes	A variety of eye conditions
Pale gums and other mucus membranes	Inflammation of the gums & mouth
Infections of the skin, urinary bladder, and upper respiratory tract	Seizures, behavior changes, and other neurological disorders
Slow but progressive weight loss, followed by severe wasting late in the disease process

I understand there are two stages of FeLV infection. What are they?

Primary viremia, an early stage of virus infection. During this stage some cats are able to mount an effective immune response, and halt progression of the disease.
Secondary viremia, a later stage characterized by persistent infection of the bone marrow and other tissue. If FeLV infection progresses to this stage, the overwhelming majority of cats with secondary viremia will be infected for the remainder of their lives.

How is infection diagnosed?

Two types of FeLV blood tests are in common use. Both detect a protein component of the virus as it circulates in the bloodstream.

ELISA (enzyme-linked immunosorbent assay) detect both primary and secondary stages of viremia.
IFA (indirect immunofluorescent antibody assay) tests detect secondary viremia only, so the majority of IFA positive-testing cats remain infected for life.

How can I keep my cat from becoming infected?

The only sure way to protect cats is to prevent their exposure to FeLV-infected cats

Keep cats indoors, away from potentially infected cats that might bite them.
Adopt only infection-free cats into households with uninfected cats.
House infection-free cats separately from infected cats, and don't allow infected cats to share food and water bowls or litter boxes with uninfected cats.

Consider FeLV vaccination of uninfected cats. (FeLV vaccination of infected cats is not beneficial.) Discuss the advantages and disadvantages of vaccination with your veterinarian.

I just discovered that one of my cats has FeLV. What should I do about my other cats?

Unfortunately, many FeLV-infected cats are not diagnosed until after they have lived with other cats. In such cases, all other cats in the household should be tested for FeLV. Ideally, infected and non-infected cats should then be separated to eliminate the potential for FeLV transmission.

How should FeLV-infected cats be managed?

Confine FeLV-infected cats indoors to reduce their exposure to other infectious agents carried by animals, and to prevent the spread of infection to other cats.
Spay or neuter FeLV-infected cats.
Feed nutritionally complete and balanced diets.
Avoid uncooked food, such as raw meat and eggs, and unpasteurized dairy products
Schedule wellness visits with your veterinarian at least once every six months. Your veterinarian should pay special attention to the health of the gums, eyes, skin, and lymph nodes. A complete blood count, serum biochemical analysis, and a urine analysis should be performed at every examination. Additionally, your cat's weight should be accurately measured and recorded, as weight loss if often the first sign of deterioration.
Closely monitor the health and behavior of your FeLV-infected cat. Alert your veterinarian to any changes in your cat's health immediately.

There is no scientific evidence that alternative, immuno-modulator, or antiviral medications have any positive benefits on the health or longevity of healthy infected cats.

How long can I expect my FeLV-infected cat to live?

It is impossible to accurately predict the life expectancy of a cat infected with FeLV. With appropriate care and under ideal conditions, infected cats can remain in apparent good health for many months, although most succumb to a FeLV-related disease within two or three years after becoming infected. If your cat has already experienced one or more severe illnesses as a result of FeLV infection, or if persistent fever, weight loss, or cancer is present, a much shorter survival time can be expected.

All info is from internet sources including Best Friends Pet Care FAQs and is for general informational purposes only. It is not intended as medical advice. C.A.R.E. is not a veterinary facility. Consult a licensed veterinarian if your pet exhibits any unusual symptoms or behavior.

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