My 3 year-old cat, Princess, just tested positive for the feline leukemia virus. She seems healthy. She is playing, eating and acting normally. What does this test result mean and what can I expect?
The feline leukemia virus (or FeLV) is one of the most important viruses affecting cats. It is found in every region of the country with a nationwide prevalence of 3-4%. In other words, three or four out of every 100 cats have FeLV.
The virus is spread in one of three ways. Most commonly it is spread by direct contact between infected and non-infected cats. FeLV is shed in large amounts in the saliva, as well as other bodily fluids such as nasal secretions, urine and feces. Cats with prolonged close contact, such as cats that live in the same area, share litter pans or food bowls, mate or groom one another are at highest risk for virus transmission.
Kittens can also be infected by the queen (mother cat) in utero during pregnancy. A less common method of transmission is via infected blood.
Once a cat is infected with the leukemia virus, it may be possible for the cat to mount an immune response that clears the virus from the body. However, only about 30% of adult cats infected with FeLV are able to clear the virus. The remaining 70% of cats will become permanently infected.
A confirmatory test submitted to a special reference lab can help assess if the infection may possibly be cleared. I recommend that you ask your veterinarian to run this test (FeLV antigen IFA test).
There may be a period of months or even years between when a cat is infected with FeLV and when she starts showing any clincal signs. So it is not unusual the Princess is still acting normally. Unfortunately, 85% of FeLV-infected cats die withing three years of diagnosis.
The virus invades cells, especially cells of the immune system and bone marrow. Over time, mush like HIV in people, the immune system becomes suppressed. This weakening of the immune system makes the cat susceptible to a wide variety of other infections that she would normally be able to fight off without difficulty.
The virus can also alter the genetic make-up of a cell. When the genetic code is changed, these abnormal cells may then result in a variety of cancers such as lymphoma, leukemia or other tumors.
It is important to carefully monitor your cat for any problems such as: loss of appetitie or decrease in drinking, vomititng, diarrhea, mouth sores, pale or bleeding gums, weakness, weight loss, infected wounds, dull or matted hair coat or any unexplained behavioral changes. If any of these signs are noted, you should contact your veterinarian immediately.
Regular visits to your veterinarian for exams and laboratory testing while your cat is acting normally should also be performed. These visits and tests may detect subtle changes not evident at home. Often early detection of a problem can lead to interventions or therapy changes that may prolong your cat’s life.
There is a vaccine available to help protect cats from contacting FeLV infection. The American Association of Feline Practitioners currently highly recommends FeLV vaccination series in all kittens, with annual boosters for adult cats at risk for exposure. Also, all cats should be tested for FeLV before bringing them into a household.
By watching your cat closely for any changes in condition or behavior, and by working closely with your veterinarian, you can provide your cat with a good quality of life for as long as possible.