What is feline calicivirus?

Photograph: iStock

Text: Tarek Abu Sham

Feline calicivirus is a viral infection that tends to occur at animal shelters or large-scale cat breeders. The virus may contribute to oral diseases, such as severe oral infections and pain and respiratory problems.

The feline calicivirus can cause ulcerations within your cat's mouth or on the nose. You may notice your cat salivating or having trouble chewing, even dropping food when they try to pick up kibble from their bowl.

Active infections may result in eye or nasal discharge, complete with conjunctivitis and sneezing. Some may develop thicker mucoid discharge, especially if they develop a secondary bacterial infection on top of the virus. There are many different strains of this virus, and you may see a variety of different symptoms, including lethargy, fever, or jaundice. Unfortunately, one strain is especially prone to causing widespread disease and happens to be highly infectious and fatal, according to VCA Animal Hospitals, so prompt treatment is needed.

Wiping your cat's eyes and nose with a clean, damp cloth can also reduce local irritation.

Feline calicivirus is most prevalent in kittens, although any cat can develop it, and it is spread mostly through secretions, such as from the eyes and nose. It can even survive on surfaces for days. After becoming infected, cats can exhibit signs of illness for weeks, and they are infectious during that whole time (with some remaining infectious for an extended period).

Your veterinarian may diagnose your cat with feline calicivirus just based upon symptoms, particularly if they have respiratory signs and oral ulcerations, and may collect samples from your cat's conjunctiva or the back of their throat and submit it to a lab for testing.

Treatment for feline calicivirus

Your veterinarian may make a variety of recommendations for treating your cat with calicivirus. Because many of these cats have painful mouths or trouble smelling, they often don't want to eat. You may need to try high-calorie foods, such as Hill's a/d, or even baby food carefully heated up. Your cat may need fluids given intravenously or under the skin to help them stay hydrated.

Certain anti-inflammatory medications may be needed, such as Onsior or meloxicam, particularly if your cat is running a high fever or develops lameness from the virus.

Your veterinarian probably won't prescribe antibiotics unless they see signs associated with a bacterial infection complicating the viral infection. In many cats with conjunctivitis, your veterinarian may prescribe eye medications to reduce inflammation or infection, from anti-viral drops to antibiotic ointments.

Steam up the bathroom by running a hot shower and bring your cat in the room for a few minutes to help reduce airway congestion. Wiping your cat's eyes and nose with a clean, damp cloth can also reduce local irritation.

Vaccinating for feline calicivirus and preventing infection

Cats benefit from the FVRCP vaccine that protects against a complex of viruses. Kittens and unvaccinated cats need to appropriately boost the first year, then following a recommended schedule, most commonly either yearly or every three years.

If one cat in the household is sick, thoroughly disinfect household surfaces, dishes, bedding, and toys. Keep sick cats isolated until they are cleared by a veterinarian, and wash your hands between handling pets to minimize the risk of transmission.

Any cat can develop feline calicivirus, and some strains are exceptionally infectious. You can reduce the risk for your cat by having them vaccinated. If you notice that your cat isn't feeling well, contact your veterinarian for an exam and follow treatment recommendations to help reduce the duration of illness.