Feline leukemia virus (Felv) is the number one infectious disease killer of cats. Owning a cat can be a great experience and we would like to make it as wonderful as possible. That is why you should know about this deadly virus. Prevention of feline leukemia is possible with a vaccine.

Feline Leukemia Virus:

Feline leukemia is a virus which belongs to the same family (Retro virus) as the virus that causes AIDS in humans. Although cats cannot contract the AIDS virus and humans cannot become infected with Felv, these two viruses have similar effects on their victims. Felv attacks and weakens a cat’s immune system. This leaves a cat more susceptible to a bacterial, viral, or fungal infection that a healthy immune system could normally fight off. Cats infected with Felv are also very prone to developing certain blood disorders called anemia and lymphosarcoma (cancerous tumors). All of these work to dramatically shorten the life of your cat.

How Is It Spread?

The virus is found in saliva, urine, blood and feces. Prolonged intimate contact between cats such as grooming, biting, sharing of litter pans and food and water bowls can pass the virus. Infected mothers can spread the virus to their unborn kittens in the womb and to kittens who are nursing. The virus is easily killed by even the most mild of disinfectants. It only survives outside the body for a
short time. After contracting the virus it travels to the cats’ lymph nodes to try and set up an infection. It is here where a large percentage of cats stop the infection and kill the virus. These cats will test negative. Of the cats that test positive for Felv, 30% will become permanently infected and eventually develop a disease related to the virus. 85% of these positive tested cats will die within 3 years, and almost half of them die within the first 12 months.

What Disease Does The Virus Cause?

The virus can affect all body systems. Therefore the infected cat can become sick with any symptom. Examples include: vomiting, diarrhea, weight loss, weakness, decreased appetite, sneezing, coughing, etc. The infected cat often shows no symptoms early in the disease.

Who Are Most At Risk?

Cats that come into contact with other cats such as cats that go outdoors, even for a short period of time.

Diagnosis

Two tests now exist for detection of the virus.

1. ELISA test
Can be run in the clinic.

2. Fluorescent Antibody Test
(FA Test)
Must be sent to a laboratory
equipped to run the test.
Results take 1 - 2 days.

In our practice, we use the ELISA test as a quick screening test and the FA test to confirm cases when there is a question about the results- i.e. in an otherwise healthy cat that tested positive.

Treatment

There is no effective treatment or cure for feline leukemia, only supportive care for the symptoms present.

Prevention Program:

1. Test all new cats or kittens before they are introduced into the household.

2. After a cat or kitten has tested negative, vaccinate them against the feline leukemia virus.

3. If your cat tests positive, ask your veterinarian to advise you.