Feline Leukemia Virus a Serious Problem

Feline leukemia virus (Felv) can cause many different diseases in domestic cats - from an immuno suppressive syndrome to cancer. While many cats are able to resist the infection or show minimal side effects, about one-third of infected cats become sick and die.

About one to five per cent of the cats that are allowed to roam free will be lifetime carriers of the virus. Carrier cats shed the virus in their saliva, urine and feces. Also, cats can transmit the disease when they fight, bite and groom each other. The virus is usually introduced to indoor populations through the inadvertent introduction of a healthy appearing Felv carrier cat.

Diseases like chronic mouth and gum infections, skin and ear infections, and chronic respiratory disease can indirectly be a result of Felv. Tumors, anemia, feline distemper and reproductive disorders are directly caused by feline leukemia virus.

Identification of Felv infected cats is made by detection of the virus in a blood sample. Veterinarians will recommend retesting 12 weeks after the original blood test to determine whether the infection is in a primary or secondary stage.

Cats found to be positive should be isolated from the negative cats (if any) and the household premises should be cleaned with a commercial detergent or disinfectant. Litter boxes and food bowls should be thoroughly cleaned or replaced.

Cats initially testing negative should be retested twice over the next eight to 12 months and during this period a quarantine should be established. No new cats should be introduced to the household. In order for the household to be considered free of Felv, all resident cats should text negative for Felv on two tests performed at least three months apart. Oral medications and routine monitoring of blood counts and Felv status is important in the treatment.

As a preventive measure, kittens are given two vaccinations three to four weeks apart and they are vaccinated annually. These vaccines have been shown to be effective in laboratory and clinical studies.