Get

In Your Inbox

Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

FIV in Cats (Feline Immunodeficiency Virus): Vet Explained Causes, Signs & Care

Share

sick cat wearing cone inside the clinic

It is always a bit concerning when your cat seems ill, so you might feel more comfortable if you took them to the vet’s office to get checked out. Your veterinarian will likely want to run several tests if your cat feels under the weather. One test, a feline leukemia and FIV test, checks for certain viral infections. You hope the test comes back negative, but then you get the bad news: your cat tests positive for FIV.

What does that ultimately mean for its care?

divider 3 paws

What Is FIV?

Feline immunodeficiency virus, or FIV, is a viral infection in cats, affecting roughly 1% to 5% percent of cats.1 It is relatively similar to the human immunodeficiency virus (HIV), although these viruses are species-specific. That means you don’t have to worry about catching FIV from your cat. When cats get exposed to FIV, the virus attacks their immune system. Without a fully functioning immune system, your cat is at risk for developing a host of different infections and may even be at a higher risk for certain cancers.

hand holding a cat FIV blood test
Image Credit: Daria Yehorova, Shutterstock

divider 3 paws

What Are the Signs of FIV In Cats?

FIV occurs in three main stages, according to the Cornell Feline Health Center:2

  • Acute phase
  • Latent phase
  • Progressive phase

The Acute Phase

During the initial stage of infection, cats are in the acute phase. The virus reproduces within T-lymphocytes, a type of white blood cell. While the virus spreads throughout your cat’s body, initially, you might see lymph node swelling or enlargement.

Your cat might show other signs at this time, including:

  • Depression
  • Anorexia
  • Fever

If you are concerned about the health and well-being of your pet, seek veterinary advice for the best course of action.


The Latent Phase

The latent phase is also called the asymptomatic phase. Infected cats don’t generally show signs during this phase. It may last for months, years, or even the rest of your cat’s life. Viral replication is slow in this period.

There aren’t many signs in this phase, but your veterinarian might detect changes in blood work, such as:

  • Low white blood cell count on a complete blood cell count (CBC)
  • Increased proteins on a serum chemistry like globulin
cat wearing plastic cone collar
Image credit: Roman G Potapov, Shutterstock

The Progressive Phase

Not all cats enter the progressive phase, but if they do, they may be affected by numerous illnesses. Secondary infections are what usually affect the cat and can shorten their lifespan.

Possible illnesses include:

  • Recurrent respiratory illness
  • Eye infections
  • Gingivostomatitis
  • Immune-mediated disorders like hemolytic anemia
  • Cancer
  • Seizures

divider 2 cats

What Are the Causes of FIV In Cats?

FIV only affects cats but can affect any type of cat, from your domestic shorthair to an African lion.

The virus particles that cause feline immunodeficiency virus don’t last long in the environment, so cats are not usually affected by passive contact, such as sharing food or water bowls or multiple cats grooming each other. If you have more than one cat and they tend to get along well, there’s a much smaller chance of your FIV-negative cat becoming infected in a stable home atmosphere than outdoor cats roaming and potentially fighting.

The most common way for FIV to pass between cats is a bite wound. As such, outdoor cats, particularly unneutered males defending their territory, are likelier to have FIV than other cats. It is less likely for pregnant or nursing females to pass the virus on to their kittens. However, it is still possible to do so through the placenta, via milk when kittens are nursing, or during the birthing process itself.

Sick cat with catheter
Image credit: Studio Nut, Shutterstock

How Do I Care for a Cat With FIV?

There is currently no cure for FIV in cats. When you get a new cat, your veterinarian should test your new addition for FIV. The most common way to check for this viral infection is to test for feline leukemia.

The test is commonly called the feline leukemia and FIV SNAP test. It is run on a small sample of blood mixed with a conjugate, using an ELISA or Enzyme-Linked Immunosorbent Assay test. If your cat is negative, your veterinarian should recheck it 2 to 6 months later, as that is the virus’s incubation period. Positive tests should be confirmed by either sending a sample to an animal laboratory, such as IDEXX or Antech, or by repeating the sample on a different manufacturer’s test.

Routine physical exams and preventative care visits are essential for all cats, but they’re especially important for cats with FIV. If your kitty is asymptomatic, visits every six months will likely be sufficient. Your cat should be seen immediately if it has any signs of illness.

Because many cats with FIV have gingivitis or stomatitis lesions in their mouths, your veterinarian will want to pay particularly close attention to your cat’s mouth. Stomatitis is a severe inflammatory condition often considered an overreaction of the cat’s immune system. If your cat is healthy enough, they should usually have annual or semi-annual dental cleanings under anesthesia.

Your veterinarian will record and monitor your cat’s weight, among other parameters. Weight loss is often one of the first signs detected in cats with worsening cases of FIV. Since there is no cure for FIV, treatments are often aimed at supportive care. Antiviral therapy is sometimes utilized, especially for symptomatic cats, such as Zidovudine (AZT). Unfortunately, this medication does not appear to improve survival times in cats. A mainstay of managing an FIV-positive cat is reducing their risk of exposure to potential illnesses.

General recommendations include:

  • Keeping affected cats indoors.
  • Spaying or neutering cats to reduce the risk of roaming.
  • Limit bringing new cats into the household.
  • Don’t feed raw diets, undercooked foods, or unpasteurized dairy.
  • To reduce the risk of exposure to parasites, keep your kitty on flea and tick preventative products, even when it is kept indoors.
tired or sick cat
Image Credit: Kginger, Shutterstock

divider 1 paws

Frequently Asked Questions (FAQ)

What Should You Feed a Fiv-Positive Cat?

FIV-positive cats should eat balanced cat food appropriate for their life stage or consider other health issues, such as food allergies. These cats should not eat raw, unpasteurized, or undercooked foods, which could increase their risk of exposure to pathogenic bacteria, parasites, and other microorganisms.

Can a Cat With FIV Live with Other Pets?

FIV is not contagious to other species, so as long as your animals get along, they should be fine together. If you have other cats, they can live with other kitties, but you should ensure they don’t fight and have ample space to minimize the possibility of conflict.

divider 3 paws

Conclusion

It can be pretty scary to learn your cat has an incurable virus, but many cats live full lives. You should reduce their risk of exposure to other illnesses and conflict with other cats. Routine wellness care is also essential to monitor your cat’s health.


Featured Image Credit: RJ22, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything cat

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.




How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Catster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.


Catster's Digital Magazine is Back!

Vet-approved health & behavior advice

Real cat stories & community features

When a Cat Becomes a Water Fountain – Why Cats Vomit After Drinking

Seeing a cat drink water and then promptly bring it back up can be confusing. Sometimes the explanation is fairly simple, particularly if...

Chatting About Sleeping Positions, Loafing & Cats in Tubes | Chatty Cattys, Episode 33

In this episode of Catster’s Chatty Cattys podcast, Dr. Karyn and Nicole dive deep into the fascinating world of feline sleep behaviors. From...

The Bite Stuff: The Truth Behind a Cat’s Sudden Nip

A cat bite that seems to come out of nowhere is one of the more confusing things a cat owner deals with. Everything...

Your Cat’s Purr Proves They’re One of a Kind

There are few sounds more comforting to a cat parent than the familiar rumble of a purring cat. You probably know your own...

More related

How to Tell if a Cat Is Spayed: 4 Vet-Reviewed Signs to Look

It’s sometimes hard for new cat owners to know whether their new female feline is spayed or not. For those uninitiated into the...

National Cat Health Month 2026: How & When Is It Celebrated?

Cat parents and enthusiasts can now dedicate a whole month of the year to felines! Our cat’s health is important; sometimes, we need...

Cat Logic: I’ll Sleep Anywhere But There (with Video)

Hi, I’m Dr. Karyn! Read my introduction to learn more about me and meet my five hilarious cats: Clutch, Cyril, Alex, Zelda, and...

How to Keep Cats From Eating Each Other’s Food: 4 Vet-Approved Methods

It can be tricky to prevent one cat from eating another cat’s food, especially if the thief is gaining too much weight and...

Keep reading

Why Does My Cat Hug My Arm? 5 Vet-Reviewed Reasons

It isn’t every day that a cat will allow you to enter the sanctity of their world. Many cats parade around the house like they own it, which we know they do, and graciously ignore you until they are ready...

cat hugs hand

Mouth Cancer in Cats: Vet-Reviewed Signs & When to Euthanize

One of the most difficult parts of pet ownership is making end-of-life decisions. Knowing when to euthanize a beloved animal companion is never easy, and there’s no right answer for every situation. Personally, I’ve had to make that choice three...

cat mouth check by vet

Can Cats Eat Peanuts? Vet Reviewed Health Benefits & Precautions

Peanuts are a delicious, high-protein snack that people enjoy all over the world. They are available in snack packs with various spices and flavorings, making them ideal for on-the-go snacking that’s healthier than potato chips or candy. As pet owners,...

Can Cats Eat Peanuts

Is Palmolive Dish Soap Safe for Cats? Vet-Approved Risks & Alternatives

Palmolive is a common dish soap that can be found in many household kitchens. Several dish soap brands, such as Palmolive and Dawn, advertise that they’re safe to use on animals. While this can be true, it really depends on...

Catster_Is Palmolive Dish Soap Safe for Cats

Wellness vs Blue Buffalo Cat Food: Our 2026 In-Depth Comparison

If you’ve spent time wandering around your pet food store, you might’ve noticed two brands that are a bit higher-end than normal: Wellness and Blue Buffalo. Each of these brands was started fairly recently, and both have cashed in on...

Wellness VS Blue Buffalo

10 Best Cat Foods for Picky Cats in Canada in 2026: Reviews & Top Picks

Having a cat that’s a picky eater can be stressful. Your pet deserves the very best nutrition, but this can be challenging when your cat seems to turn their nose up at everything that you put in their bowl. These...

cat eating

10 Best Cat Foods at PetSmart in 2026 – Reviews & Top Picks

With over 1,500 stores, online shopping, and AutoShip options to rival any of its competitors, PetSmart is a popular choice for all your pet supply needs. As a big chain store with considerable stock, it has an overwhelming variety of...

Siamese cat eating from a bowl

Can Cats Eat Dog Treats? Vet-Approved Nutrition Facts & FAQ

If your cat accidentally got into your dog’s treats, it’s normal to be a little alarmed. The good news is that, in most cases, it’s safe for your cat to chomp on a dog treat now and again. They’re not...

Can Cats Eat Dog Treats

Love Cats? So Do We! Join the Catster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.




Sign up for the Catster Email Newsletter

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.