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Feline Leukemia

by Lindsay

What is Feline Leukemia? (FeLV)
Feline Leukemia is a contagious viral infection affecting all stages of life in cats. The viral infection can potentially lead up to; anemia, weakened immune systems, and even cancer. The disease worsens over time and in most cases is usually fatal. Feline Leukemia Virus is a common disease that affects about 2% of cats in the United States.


What are the signs of Feline Leukemia? (FeLV)
Clinical signs of Feline Leukemia Virus come from the blood cells being attacked. Initially, some cats may show little signs of infection until the Virus is strong enough to take over more of the immune system. So here are some of the signs to look out for:
Pale Gums (Anemia), Decreased in eating, weight loss, poorly groomed coat, inflamed gums and mouth, fever, enlarged lymph-nodes, and chronic skin, eye, and respiratory infections.

What are the causes of Feline Leukemia? Or How can my feline contract the virus?
Feline Leukemia is spread through various different causes. Close contact within another feline that has the virus like grooming one another, sharing the same food/water bowl, and litter box(es). The feline can even contract the virus through the mothers while pregnant with kittens through the placenta or even nursing. It can even be contracted through a bite wound of a feral cat.

How can a Veterinarian diagnose my cat with leukemia?
A Veterinarian can run a simple blood test to test your cat. One of these tests, called an enzyme-linked immunosorbent assay (ELISA), is usually performed first as a screening tool, and can be run in a veterinarian's office. ELISA-type tests detect the presence of free FeLV particles that are commonly found in the bloodstream during both the early and late stages of infection.

The indirect immunofluorescent antibody assay (IFA) test is usually sent out to a diagnostic laboratory after a positive ELISA test to confirm FeLV infection and determine whether the cat has reached the later stages of infection. IFA tests detect the presence of virus particles within white blood cells, usually an indication of a more advanced infection. The majority of cats that test positive by IFA remain infected for life. In some cases, isolating the whole virus or detecting DNA of the virus using a test called a polymerase chain reaction (PCR) may be recommended to determine whether FeLV has infected the bone marrow.


Always consult with your veterinarian to determine which tests are appropriate for your cat. 


What if my cat tests positive for Feline Leukemia? What can I do?
Some cats diagnosed with FeLV can live normal lives for years, especially if they are kept indoors with minimal exposure to secondary illnesses. The average life span after testing positive for leukemia virus is less than three years. It is also important to prevent any cat interactions, such as fighting. 


Unfortunately, there is currently no definitive cure for FeLV. Veterinarians treating and managing FeLV-positive cats showing signs of disease usually treat specific problems (like prescribing antibiotics for bacterial infections, or performing blood transfusions for severe anemia).

How can I prevent my cat from Feline Leukemia Virus? (FeLV) 

You can minimize the risk of your cat getting the Feline Leukemia Virus by regular vaccination. It is HIGHLY recommended for cats that do go outside to be vaccinated for the annual Leukemia Vaccine. The American Association of Feline Practitioners recommends all kittens be vaccinated within their first year. Young kittens start the vaccine series at 8 weeks of age and receive a booster 3 to 4 weeks later. Cats at-risk should continue regular vaccination each year, while low risk indoor-only cats may discontinue the vaccine after the initial series.


Vaccinated cats will not test positive on feline leukemia snap tests.


If a cat tests positive for feline leukemia, it should not be vaccinated, as it puts excess strain on its immune system.


Any new cat should be tested for feline leukemia and FIV prior to being introduced to other cats in the household.

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