Introduction

Feline leukemia virus (FeLV) is a naturally occurring retrovirus associated with cancerous and non-cancerous diseases. It is one of the most common viruses seen in cats. The disease occurs worldwide in domestic and some wild felids. FeLV is contagious, it can lie dormant in the bone marrow for a long time, and it can be prevented by vaccination. FeLV is capable of producing a wide variety of associated diseases and symptoms. Many cats suffer from suppression of their immune system and other illnesses such as chronic respiratory infections, chronic gingivitis and stomatitis, feline infectious peritonitis, delayed healing of wounds and abscesses. FeLV is extremely unstable once outside the cat and is rapidly inactivated by most household disinfectants and detergents.

Transmission

Transmission occurs primarily through the exchange of secretions: saliva, blood, and fluids. It is primarily spread by the saliva during cat fights, grooming, mating, licking, sneezing, and sharing of food and water bowls. The virus is most concentrated in the saliva, and is less likely to be spread by urine, feces, and fleas. FeLV positive mothers pass the infection in utero and by licking or nursing the kittens. Male tomcats are at a higher risk because they tend to defend their territory and thus get into more fights.

Clinical Signs

Generally fepends on the virus type and disease stage, during the early stages of the disease many cats exhibit no clinical signs. After several weeks or months the cat's health will start to deteriorate. Examples include anemia, decreased appetite, persistent fever, diarrhea, and jaundice. Lethargy and decreased appetite are the most common clinical signs that prompted owners to seek veterinary care.

Diagnostic Testing

The preferred test is the ELISA as it is quick and readily available in veterinary clinics. Vaccination for FeLV does not affect test results since the tests look for viral antigens, not antibodies. Kittens can be tested at any age because maternal immunity does not interfere with testing. A cat with contradictory test results should be considered a potential source of infection. Cats with an expected or known exposure to a FeLV positive cat should be tested, but no sooner than 90 days after the exposure because the incuabation period of the virus may cause a false negative results. Ideally all cats should be tested for FeLV especially before a new cat is introduced into the home.

Treatment

At this time there is no provem regimen of drug treatment that directly eliminates the FeLV virus. Treatment consists of the management of secondary diseases the cats may be exhibiting. These treatments usually expand the life of a FeLV positive cat for less than a year. Because the virus is not affected by the treatment, the cat will always remain infected with FeLV.

Prevention

The best protection against any infection is by preventing any potential exposure to the virus. Besides preventing contact with a known FeLV positive cat, vaccination is another way an owner can help to prevent FeLV. The vaccine will not cause the cat to test positive for the virus. On average the FeLV vaccines commercially available are able to prevent infection in about 80 - 90 percent of cats. New cats should be tested before being introduced to a home. If you have a FeLV positive cat do not allow it to roam freely outside, as it increases it's possibility to infect other cats or to contract opportunistic infections. Infected and non infected cats should not live together. If this can not be arrange then separate quarters, food bowls, water bowls, and litter boxes should be provided.