Feline Leukemia Virus

Causes, Prevention and Treatment of the FeLV Retrovirus in Cats

Jul 19, 2008

Feline leukemia is a major cause of illness and death among cats. It can cause anemia and several types of cancer, as well as suppressing the immune system.

Despite its name, feline leukemia or FeLV is a viral infection rather than a cancer. Outdoor cats and those living in multicat households are more likely to be infected with the feline leukemia virus, which is passed from one cat to another through mutual grooming, sharing litter boxes and food dishes, and nose-to-nose contact.

The virus may also be transmitted by nursing mothers to their kittens, and via bite wounds when cats fight. Young kittens are even more likely to develop the disease than adult cats. Cats cannot transmit the virus to people.

Disorders Caused by Feline Leukemia

Because FeLV suppresses the immune system, cats may suffer from a variety of infections. In addition, the feline leukemia virus can cause other medical problems, including:

Tumours, such as lymphoma, a common cancer in cats that requires chemotherapy treatment
Reproductive difficulties, including spontaneous abortion and infertility, as well as giving birth to live kittens infected with the virus
Intestinal Inflammation, which causes depression, loss of appetite, diarrhea and vomiting
Nervous system problems, which though less common can have serious symptoms, including loss of bladder control and paralysis of the hind limbs

Prevention

There are a number of precautionary strategies you can use to protect your cats from feline leukemia infection:

Keep cats indoors – an estimated 1-2% of all stray urban cats that appear healthy have the virus, and this prevalence is even higher among sick cats
Have kittens tested for the virus during their first veterinary check-up
When adopting a new cat, have her tested for the virus before bringing her home
Have resident cats tested before bringing home a new cat
Have all cats that are at risk for the disease vaccinated against it

If you have a cat that is infected with the virus, keep that cat separated from your other cats, even if they have been vaccinated. The disease is highly infectious and may eventually be transmitted even to vaccinated cats through regular contact. Also, be sure to wash your hands after handling the FeLV-infected cat to prevent transmitting the infection to the other cats.

Treatment

In a best case scenario, the virus is identified early and the infection eliminated before other diseases occur. Early identification is more likely in cats that receive regular veterinary check-ups. However, most cats have had the virus for quite some time when it is discovered, and so treatment involves controlling the disease rather than eliminating it.

Controlling the feline leukemia virus once the cat has been infected can help to prevent the formation of tumours and other health problems. With good supportive care, infected cats may live free of illness for many years.

Caring for a Cat with Feline Leukemia

The most important aspects of caring for a cat that is infected with the feline leukemia virus are to prevent the cat from suffering stress and remove potential sources of secondary infection. The latter can be done by:

Changing water daily
Removing uneaten food at least once a day
Cleaning cat dishes very thoroughly
Keeping the cat indoors at all times

Cats with feline leukemia should have veterinary check-ups every six months, even when they are not showing symptoms of other illnesses, and their vaccinations should be kept up to date, with the exception of the feline leukemia vaccine. Once the cat has been infected, feline leukemia vaccinations are not given as they are ineffectual in cats that already have the virus.