Friday, September 30, 2016 | NHS Animal Medical Department
Feline Leukemia Virus (FeLV) is a viral infection of cats that can result in immunosuppresion and malignant neoplasia (cancer). Conditions that have been associated with FeLV infection include - but definitely are not limited to - lymphoma, leukemia, anemia, upper respiratory tract infections (URI) and stomatitis (inflammation of the oral cavity).
FeLV is most commonly transmitted from cat-to-cat through saliva during grooming or playing activities, through the sharing of food and water bowls, or through bite wounds. Transmission can also occur through blood-to-blood contamination (i.e. transfusions). Kittens are at an increased risk of exposure since mothers can transmit FeLV to their kittens during pregnancy, through nursing, and via frequent grooming.
Not all cats exposed to FeLV become persistently infected. Healthy cats with a strong immune system are often able to mount a full immune response and eliminate the infection. Some cats appear to have an inherent resistance to FeLV infection but this resistance develops with age. Kittens less than 4 months-of-age are at the greatest risk for infection. Additional risk factors for FeLV infection include living in multi-cat households, living in catteries, or frequent exposure to free-roaming or infected cats.
Currently, there is no treatment available to eliminate FeLV infections so the goal of treatment is to control the symptoms caused by any secondary infections (i.e. URI) or conditions (i.e. anemia). Since there is no cure, preventing infection is critical. The mainstays of prevention include minimizing or eliminating potential exposures to infected cats, appropriate testing, and vaccination.
There are a few different tests utilized to diagnosis FeLV, however, the most frequently used test is an ELISA blood test. This is a simple, rapid test that can be performed at a veterinary clinic and provides results within a few minutes.
If a cat has been recently exposed to FeLV or if a recent exposure to FeLV cannot be ruled out, more than one FeLV test should be performed before introducing this cat to any new cats. Most cats that have been exposed to FeLV and are going to become persistently infected will have a positive ELISA test result within 28 days of exposure. Ideally, any potentially exposed cat should be retested at least 90 days after their potential exposure to FeLV before they are introduced to any new cats.