Cats and Feline Leukemia

From Pet Talk | College of Veterinary Medicine and Biomedical Sciences, Texas A&M University
August 24, 2005

If cats do have nine lives, it may be a good thing: there are a lot of diseases out there that head straight for Felix and Morris.

One ailment that strikes fear more than any other, however, is probably the feline immunodeficiency virus, commonly called FIV. Simply put, it's a killer and one disease cat owners should be familiar with and try to prevent, says Dr. John August, a professor at Texas A&M University's College of Veterinary Medicine and Biomedical Sciences.

FIV is in the same family of diseases as feline leukemia, another deadly disease, and is a cousin of the HIV virus that affects humans. FIV is classified as a lentivirus, or "slow virus," similar to those that cause pneumonia in sheep, infectious anemia in horses, encephalitis in goats and acquired immunodeficiency syndrome (AIDS) in humans.

"The FIV virus in cats can be found worldwide," says August. In the United States, as many as 3 percent of healthy cats may have FIV, an alarming number considering there are an estimated 60 million cats nationwide. The disease cannot be passed to humans.

Among cats that are sick and are suffering from other diseases, that figure rises up to 15 percent, adds August.

Cats most likely to get FIV are males, especially those that like to roam wide areas. They tend to come into contact with more cats and acquire the disease.

Indoor cats are much less likely to acquire FIV, August explains.

The most common way a cat acquires FIV is through a bite from an infected cat, August says. "That's why a male cat that roams a lot and may get into fights with other cats is especially prone to the disease," August says.

"We know that the disease can be passed from an infected female cat to its newborn, but this is relatively rare," August adds.

"There is currently no universally effective vaccine to protect a cat from acquiring FIV infection," he continues. "The best way to prevent infection is prevent exposure to infected cats. This means keeping your cat indoors to avoid fighting with roaming cats and testing new additions to your household before bringing them into contact with your current resident cats."

What symptoms should a cat owner look for?

"Many cats with FIV infection will remain apparently healthy for a lifetime, unlike humans with HIV," August explains. "If symptoms associated with the infection do develop, the cat may develop a high fever, and loss of appetite is common. Frequent infections in the bladder and urinary tract can be a possible sign of FIV, as can skin infections and inflammations in the mouth. Some cats also develop severe diarrhea. Many cats also experience significant weight loss particularly in the later stages of the disease."

Cats that are infected with FIV are at a much higher risk of acquiring certain types of cancer, such as lymphoma.

"But many of these symptoms do not show up for years after the animal has acquired FIV," August says. "The cat may look and act perfectly healthy, but it has FIV in its system."

How can FIV be treated?

The disease is diagnosed by an FIV antibody test, August says. If the results are confirmed positive, it means that the cat has FIV probably for its lifetime and can transmit the disease to other cats.

No cure for FIV is available, August says.

"The best thing to do is to keep your cat away from other cats, because if they have other diseases, your cat can acquire them and weaken its condition severely," he explains.

"As with HIV in humans, there are some drugs that help control FIV, but nothing yet can cure it. And there is no vaccine that can prevent FIV reliability in all cats.

"Drug companies are trying very hard to come up with a cure for FIV, but just as the AIDS virus in humans, it is a very tough and complex disease to fight. If you suspect your cat might have FIV, you should immediately have it examined by a veterinarian and he or she can come up with a treatment plan for the disease."

Pet Talk is a service of the College of Veterinary Medicine and Biomedical Sciences, Texas A&M University.