Feline Leukemia Transmission to Humans

Feline leukemia (FeLV) is a serious infection that weakens a cat's immune system and leaves her prone to other serious infections. It was first discovered in the 1960s and has been an ongoing threat to the health of pet cats in the United States.

Like the feline immunodeficiency virus that causes feline AIDS, FeLV is a retrovirus that targets a cat's immune system. Retroviruses tend to be host-specific, which means that it's impossible for a person to contract feline leukemia from a cat.

How Feline Leukemia Is Transmitted

Cats can contract FeLV in several ways. The most common method of transmission is when an infected cat bites another cat and passes the virus in saliva to the other cat's bloodstream. This most commonly occurs when outdoor-only males cats fight.

A second transmission route is when an infected female cat gives birth to a litter of kittens. Some kittens become infected during birth, while others may catch the disease from drinking their mother's milk.

The virus can also be shed in blood or feces, which makes it important for you to protect your cat from exposure to other cats whose FeLV status is unknown. A simple blood test can determine a cat's FeLV status.

No cure currently exists for FeLV, but supportive treatments are available to improve your cat's quality of life after she becomes ill. Cats with FeLV must be separated from other cats for the health and safety of all the animals.

Vaccination can help protect your cat from becoming infected with the virus. The vaccination is especially recommended for outdoor cats due to their increased risk of exposure to the virus. Altered indoor-only cats have a much lower chance of contracting FeLV, so make sure to keep your cat indoors at all times and have your pet spayed or neutered.

Signs of Feline Leukemia

FeLV passes through two stages-primary and secondary viremia-after a cat has been exposed to the virus. Most cats can fight off the primary phase of the disease, but by the time the secondary stage takes hold, the cat's immune system is weakened, which leaves your cat prone to secondary infections.

Clinical signs of FeLV infection can include anemia, appetite and weight loss, eye problems, fever, gum and mouth inflammation, neurological problems, pale oral tissues, persistent diarrhea, poor coat quality, reproductive problems, seizures, skin infections, swollen lymph nodes and weakness.

Other Diseases You Can Catch from Your Cat

While it's impossible to contract FeLV from your cat, you can still catch other zoonotic diseases (those that can pass between people and animal species) from your cat, including cat-scratch dicsease, roundworms, hookworms, ringworm, cryptosporidiosis, Giardia, toxoplasmosis and rabies.

To reduce the chances of contracting a disease from your cat, follow a few simple precautions, including

  • Washing your hands thoroughly with soap and running water after touching cat feces or cleaning a litter box
  • Keeping your cat indoors to reduce her risk of being exposed to disease
  • Avoiding being bitten or scratched
  • Washing any scratches or bites you do receive with soap and water
  • Vaccinating your cat against rabies