Feline calicivirus or FCV is a common disease that causes cold-like symptoms in cats. The virus is highly contagious between cats of all types but cannot be spread to people or other pets. Calicivirus infections are most commonly seen in young kittens or in cats that are grouped together, for example in shelters.




Calicivirus can cause a fever, sneezing, discharge from the eyes and nose, red and swollen eyes, drooling, ulcers in the mouth, loss of appetite and less frequently painful joints and limping. Other viruses and bacteria can cause similar symptoms of upper respiratory disease, but in many cases definitively diagnosing the microorganism that is to blame is unnecessary, as most cats will recover uneventfully with similar treatment. Recently, an extremely aggressive but relatively rare form of calicivirus has emerged that can be deadly to a large percentage of infected cats.




For a typical, mild case of calicivirus, supportive care, including keeping the cat's eyes and nose clear of discharge and encouraging it to eat and drink is all that is necessary for a full recovery. More severely affected cats may also need antibiotics to treat secondary bacterial infections, pain relief, eye ointments, fluid therapy and nutritional support. Some cats that have been infected with calicivirus can suffer flare-ups of the disease throughout their lives. Treatment with lysine may help lessen the frequency and severity of these relapses. Vaccination against calicivirus helps prevent or lessen the severity of the respiratory form of the disease and is part of the routine vaccination protocol for all kittens and adult cats.


Written by: Jennifer Coates, DVM
Last reviewed: October 2, 2008