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What Are the Key Facts About Cat Leukemia?

By October 14, 2019Pet Care, Pet Health
What Are the Key Facts About Cat Leukemia?


The term leukemia is constructed as follows: white blood cells (leukocytes) within the blood (emia). The feline leukemia virus (FeLV) causes the white blood cell count to be drastically abnormal – either much higher or much lower in number than is usual. This abnormality in white blood cells leads to overwhelming infections and tumors. Leukemia-caused tumors are responsible for approximately one-third of feline cancer deaths.

How Do Cats Get the Feline Leukemia Virus?

FeLV commonly infects kittens below four months of age. The virus is usually transmitted to these kittens by their mothers (via the mother’s placenta, saliva or milk) or through contact with other infected cats. The virus affects individual kittens differently. The more fortunate ones will clear the virus from their systems and never become ill. Others will be permanently infected but will not show any evidence of disease for several years. In general, older cats with robust immune systems are resistant to infection.

How Do White Blood Cells (WBCs) Work in Cats?

The scientific term for a WBC is leukocyte (leuko means white and cyte means cell). WBCs serve the essential function of combating infections that cats are exposed to. There are five different types of WBCs: lymphocytes, monocytes, neutrophils, basophils, and eosinophils. With cat leukemia, it’s the lymphocytes and/or neutrophils that are usually affected. WBCs protect cats from infections in two ways:

  1. They engulf and kill foreign invaders (phagocytosis).
  2. They produce antibodies that attack viruses and bacteria in the bloodstream.

How Common Is Feline Leukemia?

The good news is that although all cats are susceptible to feline leukemia, few develop the disease (approximately one or two cats out of every hundred). Mature cats are unlikely to develop cat leukemia with the following exceptions:

  • Cats with poorly functioning immune systems.
  • Cats in high-stress situations (e.g., over-crowded living conditions).
  • Cats who already have a severe illness.
  • Highly inbred cats.
  • Cats who have received transfusions of infected blood or an injection with a needle previously used on a FeLV-positive cat.
  • Male cats that roam outdoors are more likely to carry the virus than female cats or male cats that live indoors.
  • Cats living for years with an infected cat will sometimes become infected.

What Are the Symptoms of Cat Leukemia?

Once infected, some cats are able to clear the virus from their bodies. Some quickly show symptoms of illness and die within months; others may live two to three years. Symptoms of FeLV include the following:

  • Pale gums.
  • Yellow coloration in the whites of the eyes or mouth.
  • Enlarged lymph nodes.
  • Upper respiratory, bladder, or skin infections.
  • Poor appetite and weight loss.
  • Deteriorating coat condition.
  • Progressive lethargy and weakness.
  • Fever.
  • Diarrhea.
  • Breathing problems.
  • Reproductive issues, e.g., sterility in unspayed females.
  • Stomatitis – painful inflammation of the mouth and gums.

Is There a Cure for Feline Leukemia?

Unfortunately, there is currently no cure for FeLV infection. However, if you have an infected cat, regular veterinary check-ups combined with good health care can help your pet feel well for some time and assist in protection from secondary infections. And, if your cat experiences any kind of emergency situation and you live in the Columbia SC area, bring him to CVETS for the very best in emergency care.