Feline Calicivirus (FCV)

Causative Agent: Feline calicivirus (FCV) is a virus that infects the respiratory tract of the cat. This virus often causes problems that look similar to other infections like feline viral rhinotracheitis and Chlamydia psittaci. It usually takes 2-6 days after the initial exposure before clinical signs begin.

Clinical Signs: Calicivirus infections can cause many different signs depending on the strain that the individual cat is infected with. Many cats infected with FCV will have an inflamed nose (rhinitis) and sinuses (sinusitis), discharge from the eyes and nose, and irritated eyes and surrounding tissues (conjunctivitis). Some strains cause ulcers and lesions of the tongue, gums, and nostrils. Other strains may cause a fever, pain in the joints, and appetite loss (anorexia). These infections can lead to pneumonia and secondary bacterial infections. A cat may experience one or all of the above signs.

Disease Transmission: This virus is spread by direct contact with infectious material. This can occur through a sneeze or cough, or can happen when infected hands or equipment contact a susceptible animal. Cats infected with calicivirus shed the virus continually.

Diagnosis: An initial diagnosis is often made based on the clinical signs. To get an exact diagnosis, samples form the involved areas would need to be collected and sent in to a lab for virus isolation and identification.

Treatment: The specific treatment depends on the signs that are involved. Initially a cat may require an anti-histamine, fluids, and rest. Some severe cases may require antibiotics to prevent secondary bacterial infections. Other cases may need treatment with an eye ointment/solution to prevent bacterial infections and drying. Cats with difficulty breathing may benefit from a humidifier or placement in a steam-filled bathroom. If the lesions in the mouth are severe, the cat may require a canned or very soft diet to help reduce the pain associated with trying to eat hard food.

Prevention: Calicivirus is one of the most common components in all most all feline vaccines. An annual vaccination program that is established by a veterinarian and followed by the owner is the best prevention. Keeping the pet out of stressful situations like overcrowding and boarding, along with keeping the cat away from sick animals can greatly reduce the risk of disease.