Feline Leukemia (FELV) & Feline Aids (FIV)

Feline leukemia (FeLV) & feline aids (FIV) are two common diseases in cats.

They are both caused by viruses that are similar to the human HIV virus. Humans and dogs cannot catch FIV or FeLV through exposure to FIV-positive or FeLV –positive cats. Only cats are susceptible to these diseases. These viruses target the cat’s immune system, much like HIV does in humans.

How do cats get FIV or FeLV?

FIV & FeLV are passed by bodily fluids. Most often this is due to fighting with an infected cat. An infected mother can pass both of these viruses to her kittens before they are born, or while nursing. FeLV can also be spread by contact with saliva, urine, or blood, so cats that share dishes with FeLV positive cats are at high risk for infection.

How do I know if my cat is infected?

A blood test shows whether your cat has these viruses. We recommend doing this test on all kittens and cats as soon as you get them. If your cat has been in a fight or been exposed to a cat that is positive, we recommend testing 2 months after the exposure. These infections can progress slowly, with a long interval between initial exposure and the onset of signs of the disease. Cats diagnosed with FelV/FIV infection may remain free of symptoms for years. Because their immune systems are compromised, these cats often develop illnesses that are unrelated to the virus itself.

Common health problems reported in cats in the chronic stage of FIV infection include

  • Oral-cavity infections
  • Upper-respiratory infections
  • Weight loss
  • Fever of unknown origin
  • Ear Infections
  • Skin infections
  • Low blood cell counts
  • Enlarged lymph nodes
  • Cancers
  • Kidney disease
  • Abortions or stillbirths
  • Eye disease
  • Neurologic disease, such as personality changes, tremors, or seizures

Is there any treatment for FIV or FeLV?

There is no cure for FIV or FeLV infection. Very rarely a cat infected with FeLV may revert back to FeLV-negative status, but most cats are infected for life. Treatment involves focuses on routine examination and testing and treating secondary illnesses that develop as a result of the disease. Some cats may benefit for immune-stimulant treatment to help fight off these illnesses.


The key to preventing these terrible diseases is preventing exposure. Keeping your cat indoors and not exposing it to untested cats is extremely important. If your cat does test positive, your veterinarian can help you decide the best option for them. The bottom line for them is that they should never be allowed around other cats. They must be kept indoors and quarantined. Allowing a FeLV or FIV positive cat to go outside means potentially infecting other cats.