As a board-certified small animal veterinarian, Dr. Joel Todd Leroy Prince provides comprehensive care to dogs and cats. Dr. Joel Todd Leroy Prince maintains a particular interest in veterinary cancers and their causal diseases. Feline leukemia virus, or FeLV, is the most common cause of feline cancer as well as feline immunodeficiency. FeLV affects up to 3 percent of all cats that live in US homes with no other cats, though the risk is higher among kittens and cats that live with infected peers. Feline leukemia is often asymptomatic in its earliest stages. As the disease progresses, however, a cat may begin to show symptoms that include appetite loss, weight loss, and enlarged lymph nodes. Owners of cats with feline leukemia may notice problems with the coat, skin, and oral tissues, as well as persistent diarrhea and fever. Confirmation via a blood test typically is necessary for a veterinarian to arrive at a FeLV diagnosis. Once the diagnosis is formalized, the veterinarian may recommend treatment for symptoms related to the disease. With monitoring and symptom mitigation, cats can live an average of 2.5 years with a good quality of life, though there is no cure for the disease itself. The most responsible thing owners can do is to prevent their cats from getting the infection. A vaccination is available, but since it is not 100-percent effective, owners should keep their cats away from potentially infected animals.