Can a Cat Spread Leukemia to Others?

Although human leukemia is not contagious, the disease works differently in cats. That's because feline leukemia is caused by a virus known as FeLV or feline leukemia virus. This virus belongs to the same family as the HIV virus that affects humans. Although the virus causes leukemia -- blood cancer -- in many cats, it can also cause other diseases, including bone marrow cancer or respiratory disease.

Feline leukemia can be passed on to other cats -- but not humans or other pets -- through bodily fluids. Getting into a fight and drawing blood might spread the virus from one cat to the next. So can two cats grooming each other or drinking from the same water bowl, as the virus can be transmitted through saliva. Even sharing a litter box can be trouble.

Because the virus is not airborne, you don't have to worry about leukemia spreading in your home -- as long as you keep the cat who tested positive separated from the others. As soon as the cats get together, however, the risk of contagion is very high. Pregnant cats can pass the virus to the kittens.

There's a vaccine available to prevent infection from the virus. Since leukemia in cats is always caused by the virus, preventing infection will prevent the development of the disease. There's no effective treatment for the FeLV virus. Although vets can help provide palliative care to help improve life quality, there's no cure for it. Also keep in mind that cats can carry the virus for years without showing any symptoms and can still pass on the virus to other cats during that time.