Feline calicivirus (FCV) is a fairly common viral disease that affects cats. The disease is much like the flu and is usually not serious or life-threatening.

Calicivirus is part of a group of diseases that affects the upper respiratory system. This group is called the feline upper respiratory infection (URI) complex. All diseases in the URI complex cause discharge from the eyes and nose.

Calicivirus Spread and Occurrence

Calicivirus can be spread from cat to cat in a number of different ways. The saliva and discharge from the nose, eyes and mouth carry the disease.

Calicivirus can live outside a cat’s body and can stay alive for eight to 10 days on objects such as food and water bowls, cat toys, cat bedding, litter boxes and even human clothing. The disease is also resistant to many types of disinfectant, making it even harder to protect against.

While the disease can affect cats of all ages and breeds, it is most common in:

  • cats that are stressed, whether physically (i.e., living in high or low temperatures) or psychologically (i.e., cats that have recently been moved to a new home or cats that have recently been introduced to a new cat)
  • cats that don’t get enough ventilation
  • cats that live in overcrowded conditions
  • cats that live in unsanitary conditions
  • kittens
  • multi-cat households
  • pet adoption centers or animal shelters.

Calicivirus Symptoms

Calicivirus symptoms vary from cat to cat in both occurrence and severity. This is partly due to the fact that there are many different strains of calicivirus. Some cats may not experience symptoms, but may still be able to pass on the disease to other cats. Others may experience symptoms and recover, but remain contagious for many years to come. Cats without symptoms that are still carrying calicivirus are called latent carriers.

Calicivirus symptoms include:

  • arthritis
  • change in appetite
  • difficulty breathing
  • discharge from the eyes and/or nose
  • fever
  • pneumonia
  • sneezing
  • sores in the mouth (known as oral ulceration)
  • tenderness of the joints or muscles (often results in a change in the cat’s activity level)
  • ulcers around the claws or on the bottom of the paws
  • upper respiratory system issues.

Symptoms usually appear suddenly and come on quickly about three or four days after disease exposure in cats with calicivirus, so it’s important to see your veterinarian as quickly as possible if symptoms appear to ensure you get an accurate diagnosis and learn about treatment options.

Recovery will usually begin on its own about one week after symptoms appear. This will happen as soon as the cat’s immune system begins to fight the disease.

Calicivirus Treatment

Treatment for calicivirus will vary depending on the symptoms the cat is experiencing, but includes making sure the cat is comfortable. Owners can do this by:

  • making sure food and water are readily available and nearby
  • making sure food is soft enough to eat (especially in cats with mouth ulcers)
  • making sure the room is a comfortable temperature and is well-lit and ventilated
  • making sure to keep the cat’s nose and eyes free of discharge by wiping any discharge away periodically.

In some cases, it may also be helpful to use a humidifier in the room the cat is staying in. This will break up excess mucous. This can also be achieved by taking the cat into the bathroom when you are taking a hot shower.

Any other symptoms or infections caused by calicivirus can often be treated with medication, including:

  • eye ointments to treat and prevent eye infections or conjunctivitis (sometimes known as pink eye)
  • oral antibiotics
  • pain medications for arthritis symptoms
  • vaccination to prevent any further symptoms of the disease.

Calicivirus Prevention

The calicivirus disease can be prevented by vaccination, but the virus may still be present. Symptoms simply won’t occur in cats that have been given the calicivirus vaccine, though they may still be able to transfer the disease to other cats.