FeLV spreads through close contact such as mutual grooming, shared food bowls, and bite wounds. Kittens are especially vulnerable. Some cats clear the virus naturally, while others become persistently infected and can shed the virus for life. Testing involves a simple blood test (ELISA) at any veterinary clinic. There is no cure, but supportive care, indoor-only living, and regular veterinary checkups can help FeLV-positive cats live comfortably for years. Vaccination is recommended for cats with outdoor access or exposure to untested cats. Keeping FeLV-positive cats separated from negative cats prevents household spread.