- At the same time, other cats exposed to the Feline Leukemia Virus can go months or years without experiencing any symptoms. Interestingly, some cats are able to defeat the virus without any medical attention. The cats immune system is strong enough to fight it off on its own. This is also why it is more likely for older cats that have pre-existing conditions to get serious effects from FeLV.
During the early stages of infection, it is common for cats to exhibit no signs of disease at all. Over time, however, (weeks, months, or even years) an infected cat's health may progressively deteriorate or he/she may experience repeating cycles of illness and relative health.

- Testing should be repeated if results conflict with clinical signs, when risk factors persist, or if the cat is very young. In some situations, a fluctuating viral load may require multiple evaluations to confirm infection status. Consulting a veterinarian ensures accurate interpretation and proper timing for any necessary retesting. Early and accurate detection helps guide decisions on vaccination, quarantine, and supportive care. Feline Leukemia Virus (FeLV) and Feline Immunodeficiency Virus (FIV) both weaken a cats immune system by attacking infection-fighting cells, but they differ in transmission and progression.

Feline leukemia in cats: Know the symptoms and explore treatment options with trusted vet advice from (). Learn how to protect your cat!
