The words might seem alarming: “Positive for FIV.” Because many people are unfamiliar with feline immunodeficiency virus, it can seem like a daunting diagnosis for potential adopters.

Yet the myths and misconceptions around FIV—such as the mistaken assumption that it is a “death sentence”—might actually be more damaging than the disease itself. That’s because these beliefs can make it harder for FIV-positive cats to find homes or even lead to unnecessary euthanasia based on outdated veterinary advice. Here, five veterinarians answer common questions—and bust myths—about FIV cats.

What is FIV in cats?

FIV is one of the most common infectious diseases among cats. In North America, around 3-5% of healthy cats are FIV-positive. Similar to HIV in humans, the virus can weaken a cat’s immune system, making them vulnerable to other infections.

“Regular infections that might affect a cat, like gum disease or an upper respiratory infection, those can be much more severe in a FIV-infected cat because they won’t necessarily have the immune system fully functional to fight those off as efficiently,” says Dr. Eileen Jefferson, New York state representative for the Humane Society Veterinary Medical Alliance and owner/founder of veterinary practice Ethical Veterinary. However, “many, if not most, [FIV-positive] cats don’t actually progress to that level of disease.”

The virus primarily passes through deep bite wounds from an infected cat—the type of bites that occur during aggressive fights, not playful interactions. It can also spread through sexual contact or from a mother to her kittens, but these instances are rare. Unneutered male cats who roam freely outdoors are most likely to be infected because they’re most likely to fight with other cats.

The virus is cat-specific and can’t spread to other species, including humans. There is currently no cure for FIV and no vaccine to protect against it in the U.S.

Can cats with FIV live healthy lives?

“I think the biggest misconception is that FIV-positive cats are definitely going to live a lower quality of life and [have] shorter life spans,” says Dr. Bruce Kornreich, director of the Cornell Feline Health Center in Ithaca, New York.

Cats with FIV often have similar life spans to cats without it: Studies conducted in 2010 and 2022 found that an FIV diagnosis wasn’t associated with decreased lifespans. In fact, cats can remain asymptomatic for years or even their entire lives.

Is it safe for FIV-positive and -negative cats to live together?

Dr. Zarah Hedge, chief medical officer of the San Diego Humane Society, says some people believe that FIV-positive cats should always live separate from other cats. Not true, she says: FIV-positive and -negative cats can live together as long as all cats are spayed or neutered, remain indoors and interact peacefully.

“If you have indoor-only cats [who] are fixed, the chances of them getting into a fight—especially with tooth penetration—is extremely minimal, to the point that most veterinarians would not discourage someone from having an FIV-positive cat in their home with other cats,” Jefferson says.

Sharing household items (such as toys, food bowls and litter boxes) and grooming each other “does not appear to be an efficient route of spreading the virus,” according to the Cornell Feline Health Center. Jefferson says that the virus doesn’t survive long in an open environment and needs direct contact with a cat’s blood to infect them.

To help reduce the chances of an aggressive interaction and keep all cats content, owners should slowly introduce new cats into their homes. “The stress of the introduction of a cat into the household can be very hard on cats,” particularly immunocompromised cats, says Dr. Elizabeth Colleran, medical director of Chico Hospital for Cats in Chico, California, and former president of the American Association of Feline Practitioners.

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How can I protect my FIV-positive cat’s health?

While FIV-positive cats can enjoy long, healthy lives, they can be hit harder by secondary infections and are more likely to develop conditions like gingivitis and anemia. “Most veterinarians currently recommend exams at least twice a year for older cats and cats with chronic medical conditions such as FIV infection,” says Dr. Barbara Hodges, Humane Society Veterinary Medical Alliance program director of advocacy and outreach.

Watch for FIV-cat symptoms such as sneezing, unusual urination, poor coat condition, lack of appetite, inflammation of the gums and mouth, and diarrhea, and promptly visit the vet if these issues arise, says Jefferson. The American Association of Feline Practitioners recommends against raw food diets, which can expose cats to dangerous pathogens found in uncooked meat.

Experts also urge pet owners to keep their FIV cats indoors, not only to protect other cats but to shield FIV-positive cats from infectious diseases they might pick up outside. And make sure your indoor cat is stimulated and engaged, says Colleran. Boredom can lead to stress, and higher stress levels can make FIV-positive cats more susceptible to health issues. Although other cats can be a great source of companionship, too many can become an added stressor, says Kornreich.

Is there anything else I should know about FIV?

Although many veterinarians understand that FIV-positive cats can live long, healthy lives, some still recommend euthanasia even if the cat is otherwise healthy. Pet owners shouldn’t be afraid to get a second opinion in this case. Dr. Heather Kennedy, chief of veterinary medicine at the KC Pet Project in Kansas City, Missouri, also notes that the recommendation to euthanize a cat solely because the animal tests positive for FIV is not in accordance with the American Association of Feline Practitioners’ guidelines.

In fact, some shelters and rescues have stopped testing all cats for FIV due to the disease’s low prevalence rate, concerns about the accuracy of test results and the high cost of testing. And increased awareness among the general population has appeared to help FIV-positive cats get adopted. At the San Diego Humane Society, cats diagnosed with FIV generally get adopted at the same rate as other adult cats. Not only are they typically “big, super cute, friendly male cats,” says Hedge, but “they’re usually lovebugs, so I feel like that helps them get adopted.”

“A lot of FIV-positive cats are just really nice cats that like other cats,” Kennedy adds. Many FIV-positive cats lived outdoors, where they learned to adjust to new experiences. And those chosen to enter an adoption program tend to be sociable, she says.

Potential adopters shouldn’t hesitate to talk to shelters, rescues and their veterinarian about any questions or concerns. They might even end up adopting a companion they wouldn’t have considered.

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