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Feline Leukemia Virus (felv)

Nov 4, 2011 · Updated Feb 2, 2012 · ·
  1. Anne

    What is FeLV?

    Feline Leukemia Virus (FeLV) not only causes leukemia (blood cell cancer), as its name implies. This virus is in fact responsible for various manifestations of disease.

    FeLV is a retrovirus that, much like FIV, may damage the cat's immune system and lead to a multitude of serious and often fatal medical conditions. In fact, according to the American Veterinary Medical Association (AVMA), FeLV is associated with the death of more cats than any other pathologic condition.

    Not all cats that are exposed to FeLV are infected. Of those infected, about a third will gain full recovery within weeks and will not be further affected; another third will become carriers of FeLV, but may remain in this state for many years; and only one-third will immediately get the active form of the disease.

    Who's at Risk?

    FeLV can be transmitted between cats via body fluids. Blood, saliva, mucus, urine, and feces can all be a source of infection.

    Cats that come in contact with other cats that are FeLV positive (whether carriers or sick) may contract the disease through mutual grooming, bites, and even sharing feeding bowls or litter trays.

    FeLV is more common among cats living in multiple cat households, but cats that are allowed to free roam outside may come in contact with FeLV positive cats and are therefore also at risk.

    Symptoms of FeLV

    Clinical signs are extremely diverse but include fever, lethargy, poor appetite, weight loss, anemia, jaundice, diarrhea or constipation, enlarged lymph nodes, respiratory distress, and excessive drinking and urination.

    Since FeLV damages the cat's immune system, severe, chronic illness may also indicate FeLV. Cancer, in the form of lymphoma or leukemia (cancer of blood cells), occurs in some FeLV-infected cats.

    Diagnosis can be made using either of two tests -
    • The Elisa test is a rapid screening test for FeLV. It can be performed in the vet's clinic using a saliva sample.
    • The IFA test is a lab test that detects the virus in a blood sample.
    Since FeLV usually has more than one stage, it is sometimes necessary to have both tests performed.

    Treatment of FeLV

    Unfortunately there is no cure for FeLV. Infected cats are treated according to their specific symptoms. Proper care of secondary infections may help to extend the cat's life span and improve its general well being.

    Prevention of FeLV

    There are several FeLV vaccinations available that can enhance the cat's ability to fight off any future FeLV infections, but they do not ensure total prevention. It is important to take the necessary precautions against FeLV even if your cat is vaccinated.

    Some safety measures against FeLV:
    • Vaccinate your cat against FeLV. This vaccine is as safe as any other common vaccine for cats.
    • Do not overcrowd cats in one household. Overcrowding cats increases their risk of exposure to FeLV. It also increases stress levels for the cats and makes them more susceptible to disease.
    • Be careful when introducing a new cat into your household. Make sure that the cat is FeLV negative before letting it join your other healthy cats. The cat must be tested for FeLV twice in the space of several weeks. During that time it must be quarantined.
    • Keep your cats indoors at all times. Cats should be let outside only under your direct supervision. You should make sure they avoid contact with other cats.

    Comments? Leave them using the form below. Questions? Please use the cat forums for those!

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  1. kassandranoriega
    Today I took in my two year old cat to a specialist after a month of trying to figure out what was wrong with her. Her current veterinarian did all the testing she could to tell me my cat’s results were all negative. She had swollen lymph nodes, a fever and was very mellow. After antibiotics she went 85% back to normal then fell ill again two weeks later but this time her weight was declining and had to be put on wet food. We got a second opinion at the ER and they said the same thing and both her current veterinarian and the ER referred me to the specialist. He did more blood work to tell me she had a “faint positive” of leukemia and I fell apart. My baby is the sweetest soul and I felt like I was gonna lose my baby right then and there. Tomorrow morning we go for a biopsy to get a for sure answer and hope to find out Wednesday or Thursday. How did some of y’all process this? I’ve been crying so much. I don’t wanna leave her side and it’s hard when I’m a full time college student and working part time Monday- Friday. All I wanna do is be with her every second. Any advice?
    1. Furballsmom
      Hi Kassandranoriega!
      I know you started a thread about your cat and by doing so received a lot of input support and suggestions from members who participate in active forums. I hope that she and you are ok!
  2. sukeyforcats
    I trapped and tried to rescue a stray cat after feeding her for 9 months. My veterinarian told me she was FeLV positive. I have 4 adult cats at home, two are FiV positive. I had to make a decision that minute at the veterinarian office. I asked the vet to euthanize my this stray I love. Maybe i didn't understand my choices. I do not have much room so separating all the cats cannot be guaranteed. I have a large cage for the stray, but she wouldn't be in it all the time. One unexpected door opening and all the cats would face each other. Sweetie, my stray had a clipped ear. She had been TNR'ed and wouldn't they have found FeLV  at that time if she had it? Does that mean she was bitten as an adult? Somewhere in the conversation about bringing my 4 cats to be tested and vaccinated i think the doctor said we should re-test Sweetie in 3 weeks to see if she had a false positive. I mis her so fiercely today i am doubting my decision. Did I euthanize a cat who had a chance at a comfortable life. When the veterinarian told me her condition I got overwhelmed with his suggestions and thought at the time i couldn't manage to bring her into my home. Now I think I asked them to take away a cat who had a chance, I just didn't give her the chance.
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