Feline Immunodeficiency Virus or FIV (Feline AIDS)

Written by Small Door's medical experts

Feline immunodeficiency virus (FIV), also commonly referred to as feline AIDS, can pose a serious health risk for cats. FIV may result in reduced immune function, which, as with the human immunodeficiency virus (HIV), can lead to a variety of other associated conditions. There is no cure for FIV.

In This Article

What is FIV in cats

Feline Immunodeficiency Virus (FIV) is a common virus in cats around the world. This widespread infection is often referred to as feline AIDS because it acts in a similar fashion attacking the immune system of the cat and targeting white blood cells. This weakened immune system can also make cats susceptible to other diseases or secondary infections unrelated to FIV.

Unfortunately, FIV is not curable and there is no effective treatment, although there is a FIV vaccination that can be given as a preventative measure. 

Does testing positive for FIV mean my cat has feline AIDS?

Testing positive for FIV does not necessarily mean your cat has feline AIDS. FIV tests detect antibodies and infection in your cat’s blood, so while it does mean your cat has been infected, the virus may be dormant or it could be years before your cat will actually display signs of the illness.

Signs & symptoms of FIV in cats (Feline AIDS)

Symptoms of FIV can range widely. Some cats may show one or more symptoms after the initial infection, while others may experience symptoms so mild they go undetected. After this initial infection phase, cats enter an asymptomatic period that can last anywhere from months to years.

FIV can cause the following:

  • Fever

  • Lethargy

  • Gingivitis and other oral infections

  • Ataxia (lack of coordination, especially when walking)

  • Change in mental awareness

  • Seizures

  • Uveitis (inflammation of the anterior chamber of the eye)

  • Cancer

FIV symptoms during the initial phase can range in intensity. Infected cats may experience an intermittent fever, oral infections, neurological signs like ataxia, and inflammation of the eyes. As the disease progresses, other developments like certain types of cancers, secondary infections, and health conditions may occur as a direct result of the cat’s reduced immune function. This is why opportunistic infections like urinary tract infections, skin infections, and gastrointestinal infections are common in FIV-positive cats, as well as cancers like lymphoma and leukemia.

How does a cat get FIV (Feline AIDS)?

Cats contract FIV through close contact with other cats. The most common transmission vector is a bite wound, since feline saliva carries the virus (one of many ways in which FIV differs from HIV). But the virus can also be spread during blood transfusions, through contaminated equipment, from mother to kittens across the placenta, through cats grooming and licking one another, through sharing water bowls and via most feline bodily fluids.

Due to the nature of transmission, older, outdoor, unvaccinated, and intact male cats carry the highest risk of contracting FIV. However, any cat can contract the disease.

Diagnosing feline immunodeficiency virus (Feline AIDS)

Diagnosing FIV in cats can sometimes be difficult. The transient nature of the fever and initial symptoms can be overlooked by owners and veterinarians, and FIV is not always initially suspected in cases of oral infections or uveitis.

However, most veterinarians recommend testing cats for FIV at some point during their lives. Typically, tests are carried out when cats are first acquired as new pets; if they have escaped the house for a period of time; or when they have been exposed to an infected or potentially infected cat. Most veterinarians also test for FIV before administering an FIV vaccine, since the vaccine itself can generate a positive test result. (Confirming that a cat is FIV-negative before vaccination means that if she tests positive afterwards, the vet knows that it’s likely a false positive secondary to vaccination and not a true infection.)

If there’s any reason to suspect that your cat’s symptoms may be a sign of FIV, or if your cat has an unknown FIV history, your vet will recommend a blood test for FIV. These results may need to be verified with further testing, and your veterinarian may also suggest additional diagnostics depending on which organ systems are involved in the infection.

FIV treatment for cats (Feline AIDS)

Healthy FIV-positive cats do not require treatment. If the disease progresses, however, cats are treated with supportive care. There’s no treatment for FIV per se, but the symptoms or illnesses that come about as a result of FIV will be handled on a case-by-case basis. For instance, secondary infections like urinary tract infections can be treated and eliminated; other conditions, like cancers, are treated with the appropriate medications and protocols.

Is there a cure for FIV (Feline AIDS)?

There is no cure for FIV. However, most cats with FIV live healthy, happy lives during the asymptomatic period, and treatment options are available to manage secondary conditions.

While precautions should still be taken to prevent the spread of this disease, a diagnosis of FIV is by no means a death sentence. If your cat is FIV-positive, it simply means you should be aware of the risks and treatment options for your cat to keep them as healthy as possible.

Is FIV (Feline AIDS) Contagious for Humans or Other Pets?

FIV is not contagious for humans and pets of other species. However, it is highly contagious to other cats, and even cats who have been vaccinated for FIV can be at risk.

Can FIV be transmitted to dogs or humans?

No. FIV is not contagious for humans, dogs, or pets of other species. However, it is highly contagious to other cats, and even cats who have been vaccinated for FIV can be at risk.

What is the cost of treating feline immunodeficiency virus (Feline AIDS)?

The cost for treating FIV will vary from case to case and over the course of the cat’s lifetime. After the initial diagnostic costs and the treatment of any initial symptoms, most owners can expect a grace period from further FIV-related medical bills until the disease enters its second stage. Unfortunately, the reduced immune function associated with feline AIDS may result in infections and even cancer, which can be costly to treat over time.

Recovery and management of FIV (Feline AIDS)

There is no cure for FIV, but the disease can be managed. Keeping your cat healthy and up to date on all vaccines will reduce the risk of certain infections and medical conditions. Regular visits (every six months) will also help catch any potential complications, like tumors, before they progress.

Cats with FIV should be neutered or spayed as soon as possible to prevent passage of the infection to other cats and offspring. If possible, FIV-positive cats should be housed exclusively alone or with other FIV-positive cats, and kept indoors to reduce the spread of infection. Keeping them indoors also helps prevent FIV-positive cats from picking up secondary infections that may be harder to treat with reduced immune function.

(Note: Because most cats with FIV live fairly healthy lives, most shelters have a fairly relaxed view about FIV. Owners of FIV-negative cats are not discouraged from adopting an FIV-positive cat.)

Unfortunately, cats with FIV often succumb to feline AIDS-associated conditions, like cancer. Your veterinarian will discuss any end-of-life care and decisions as the time approaches, but a diagnosis of FIV does not require immediate euthanasia. These days, many cats live normal or almost-normal lives, as long as they are provided with good, regular veterinary care.

Preventing feline immunodeficiency virus (Feline AIDS)

FIV in cats is a preventable condition. As outdoor cats are at an increased risk, keeping your cat indoors will reduce their risk of contracting FIV and other infections. Testing new cats for FIV before incorporating them into the household will also prevent accidental introduction of FIV into your home. Sometimes, however, accidents do happen. If your indoor cat escapes the house or comes into contact with potentially infected cats, you may want to get him or her tested for FIV.

Is there an FIV vaccine for cats (Feline AIDS)?

There is a vaccine for FIV, but it isn’t as effective as most other vaccines; these days, many vets consider FIV to be a non-issue and not worth the trouble of vaccinating against. Keep in mind that for most indoor cats, the risk of contracting FIV is quite small, even if they live with an FIV-positive cat.

However, talk to your veterinarian about your cat’s risk factors to see whether he or she recommends the vaccine.

Summary of FIV (Feline AIDS)

FIV (Feline AIDS) impacts cats’ immune systems, leaving them more vulnerable to infections and diseases. While there’s no cure, FIV-positive cats can still live healthy, happy lives with the right care. Owners simply must be aware of the risks for their cat and manage them appropriately to keep them as healthy as possible.

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