Can Cats Catch Flu A? | What Vets Want You to Know

When your cat starts sneezing or develops a runny nose, it’s easy to assume they’ve caught whatever bug is going around the house. The term “cat flu” gets used for just about any feline sneeze or sniffle, which leads to plenty of confusion.

The short answer is yes, cats can catch Influenza A from humans. But here’s the catch: the vast majority of what vets call “cat flu” has nothing to do with human flu viruses at all. Understanding the difference matters for treatment and recovery.

The Usual Suspects: Feline Herpesvirus and Calicivirus

The most common culprits behind a cat’s respiratory infection aren’t influenza viruses. They’re feline herpesvirus (FHV-1) and feline calicivirus (FCV). Together, these two account for about 90% of feline upper respiratory infections, according to the Cornell Feline Health Center and the Merck Veterinary Manual.

Feline herpesvirus is extremely widespread. Up to 97% of cats are exposed to it in their lifetime, making it a routine trigger for symptoms, especially during stress. The virus causes feline viral rhinotracheitis, a persistent upper respiratory tract infection that can linger and reactivate.

Why the “Flu” Label Sticks

The symptoms look almost identical to human flu: sneezing, nasal discharge, eye discharge, fever, and lethargy. Feline calicivirus often adds painful oral ulcers, which herpesvirus typically does not. Most cats with calicivirus recover within seven to 10 days with supportive care, though some become long-term carriers.

When Cats Catch Human Flu (Influenza A)

If you’ve had the seasonal flu and your cat starts acting off, it’s natural to wonder if you passed it to them. Research suggests that close contact between cat owners and their cats is likely to lead to the spread of influenza A viruses from humans to cats. The CDC confirms that influenza can spread in cats the same way it does in people.

That said, true influenza A infection in cats is far less common than the everyday feline herpesvirus or calicivirus. Healthy adult cats tend to handle human influenza A fairly well. The bigger concern for vets right now is avian influenza A (H5N1), which can cause more severe illness in cats exposed to infected birds or contaminated raw dairy.

• How infection happens: Droplets from a sick person’s cough or sneeze land on the cat’s nose or mouth, or the cat ingests the virus from contaminated surfaces or raw food.
• Symptoms to watch for: Fever, lethargy, coughing, sneezing, nasal discharge, and red or runny eyes. They mirror the feline viruses.
• Risk of cat-to-human spread: The AVMA considers the risk of a cat passing H5N1 to a human extremely low, though it may increase with prolonged, unprotected exposure to a sick cat.
• What to do if you’re sick: Limit close face-to-face contact with your cat while you’re contagious. Wash your hands frequently and avoid sneezing near them.
• When to test: A vet can run a PCR panel to tell the difference between influenza A and the common feline viruses.

How to Tell the Difference (And When to Worry)

Because the symptoms of influenza A, feline herpesvirus, and feline calicivirus overlap so heavily, it’s nearly impossible to tell them apart without a vet visit. The CDC’s cat flu transmission page highlights key differences in origin and severity.

Most cats with calicivirus recover within seven to 10 days with supportive care, but some become long-term carriers. A cat carrying feline herpesvirus might only show symptoms after a stressful event, which weakens their immune system enough for the virus to reactivate.

What To Do If Your Cat Starts Sneezing

If your cat develops a sniffle, your first instinct shouldn’t be to panic. You should isolate and observe carefully. Here’s a practical sequence to follow at home.

1. Isolate the sick cat. If you have multiple cats, separate the sneezing one immediately. Feline herpesvirus and calicivirus are highly contagious to other cats through shared food bowls, litter boxes, and close contact.
2. Clean their nose and eyes regularly. Use a warm, damp cloth to gently wipe away any discharge. Keeping the face clean helps your cat breathe and encourages them to eat.
3. Increase humidity in the room. Running a vaporizer or humidifier can help clear nasal passages. Cornell’s Baker Institute recommends this alongside saline nose drops to keep the nose moist.
4. Encourage them to eat. Cats lose their appetite if they can’t smell their food. Warm up their wet food slightly to make it more aromatic. Strong-smelling foods like tuna can help tempt a picky eater.
5. Call your vet. Reach out if your cat stops eating, has open-mouth breathing, or seems very lethargic. A vet can test for influenza A versus the common feline viruses and prescribe medications like bromhexine to reduce congestion.

For cats with feline herpesvirus or calicivirus, supportive home care is the mainstay of treatment. Vets may prescribe medications like bromhexine to reduce congestion, and antibiotics if a secondary bacterial infection is suspected.

The Research and What It Means for Your Cat

Research hosted by the NIH has confirmed that while cats were historically considered resistant to influenza, they are indeed susceptible to some influenza A viruses originating in other species. A 2021 review in the journal Viruses mapped out how these spillover events happen. The NIH/PMC review on cats susceptible influenza provides a thorough breakdown of which strains pose the biggest risk.

For the average house cat, the greatest respiratory threat remains feline herpesvirus and calicivirus, not human flu. Cats of all ages are capable of catching the flu, as well as upper respiratory infection caused by those feline-specific viruses.

If you have recently been sick with the flu, it’s wise to limit close face-to-face contact with your cat while you are contagious. Good hand hygiene and keeping shared surfaces clean can reduce the chance of passing the virus to them.

The Bottom Line

Cats can catch influenza A from humans, but the term “cat flu” is typically dominated by feline herpesvirus and feline calicivirus, which together account for roughly 90% of feline upper respiratory infections. True influenza A infections in cats are less common and generally mild in healthy adults, though avian H5N1 requires extra caution.

A veterinarian can run a PCR panel to determine whether your cat’s symptoms are from a feline-specific virus like herpesvirus or calicivirus, or from a true influenza A spillover event, which helps guide the right supportive care for your cat’s age, vaccination status, and overall health.