What to Do if Your Cat Has the Flu

Feline upper respiratory infection (URI) is sort of like the flu in humans. It’s primarily caused by viruses that lead to symptoms like a runny nose and sneezing. Usually, one of the most recognizable signs is heavy discharge from the eyes that can give a cat a squinty, stuffed-up appearance. While this infection can be caused by a few different viruses, it is often accompanied by bacterial infections. Its symptoms can be mild or very severe.

The main symptoms of an upper respiratory infection are:

• Runny nose and eyes
• Sneezing
• Coughing
• Sniffling
• Voice changes (like an unusually raspy meow)
• Fever
• Mouth or nose ulcers

A cat could have one or all these symptoms when it has an upper respiratory infection. Kittens usually have the most severe symptoms because their immune systems are immature.

The severity of a feline upper respiratory infection can vary a lot. URIs are caused by a few different viral strains. Ones caused by the feline herpes virus (FHV) are often more severe, and cats infected with FHV carry it for life.

The other virus responsible for cases of URI is the feline calicivirus (FCV), which tends to produce milder symptoms like eye discharge but can lead to mouth ulcers. Most cats recover without any issues, but elderly cats and ones with compromised immune systems are at risk. One of the main dangers is the infection spreading to the lower respiratory tract, developing into pneumonia.

Some less common causes of URIs are feline chlamydiosis, a bacteria-based infection, and fungal infections, most commonly caused by cryptococcus neoformans. Outdoor cats are at most risk of exposure to this common fungal spore.

Feline upper respiratory infections caused by viruses spread as easily as the common cold in humans. Cats who have lived in group settings, such as in a colony or at an animal shelter, are very likely to have been exposed. Cat flu is transmitted through direct contact, such as grooming, and indirectly spread through shared food bowls, bedding, or human hands.

Most otherwise healthy cats can recover within two weeks with home care. Isolate the sick cat from the other cats in the household to prevent transmission. Another step to stop the spread is to wash its food bowls, litter trays, and bedding separately from the ones that your other kitties use. Make sure to wash your hands after you pet a sick cat to avoid spreading the cat flu to other cats.

Sometimes home care isn't enough, and a cat with an upper respiratory infection needs treatment from a veterinarian. Contact a vet if:

• Your cat refuses food for more than 24 hours.
• Nose or eye discharge is yellow or green (antibiotics may be needed).
• Your buddy is panting or breathing with its mouth open.
• Your cat is very lethargic.
• Kitty has been throwing up or has diarrhea for more than 24 hours.
• Your cat doesn’t seem to be getting better after one week of home care.

A veterinarian usually diagnoses feline upper respiratory infection by observing clinical signs and ruling out other causes. Lab testing usually isn’t necessary, but it can be carried out to confirm the diagnosis and pinpoint the exact strain of virus or bacteria causing the illness. In that case, your vet will take a mouth or eye swab to send to a lab for analysis.

If your vet determines that the cat needs treatment for its upper respiratory infection, they could prescribe antibiotics to resolve any secondary bacterial infections. Very congested cats could benefit from steam inhalation or nebulization. A stuffy nose puts a damper on kitty’s sense of smell, making them lose their appetite. Try amping up the appeal of your cat’s food with a bit of fish oil or by warming up wet food. If the cat isn’t eating or drinking enough, it may need to be hospitalized so it can receive IV fluids and feeding via a tube.

A vaccine against feline upper respiratory infection is part of the standard yearly regimen provided by most veterinarians. However, it doesn’t 100% protect a cat from URIs but can help lower the severity of symptoms.

Usually, the time you need to be most careful and watchful is when you bring a new cat home from a shelter or other setting with multiple felines. Consider keeping the new arrival isolated from your other cats for eight to 10 days while it adapts to its new home and you watch for symptoms.

While cats can carry germs that have the potential to make humans sick, the ones that cause feline upper respiratory infections cannot spread to humans. Infections in cats caused by the feline calicivirus or feline herpes virus are also not transmissible to other animals, so you don’t have to worry about dogs, birds, or other pets in your household picking up a case of cat flu.