Feline Viral Rhinotracheitis
Feline viral rhinotracheitis (FVR), caused by feline herpesvirus 1, is an upper respiratory infection of cats. It can also be referred to as feline influenza or feline coryza. FVR causes one-half of respiratory disease in cats. Feline calicivirus is another of the most common diseases to cause respiratory infection in cats.
It is very contagious and can cause major problems including death from pneumonia in young kittens. It is transmitted only through direct contact. It reproduces in the nasal and nasopharyngeal tissues and the tonsils. Viremia, where the virus is present in the blood is rare. Normally the virus is shed in saliva and in eye and nasal secretions. It has a two to five day incubation period. The virus is shed up to three weeks post infection. Most disinfectants, antiseptics, and detergents are effective against the virus.
Early symptoms include coughing, sneezing, nasal discharge, conjunctivitis, fever, and loss of appetite. Usually these symptoms resolve after four to seven days, however, secondary bacterial infections cause persistent clinical signs for weeks. It often results in corneal ulcers.
Clinical signs usually lead to diagnosis, especially corneal ulceration. Through virus isolation and immunofluorescence, a definitive diagnosis can be given. Many cats are sub-clinical carriers of feline herpes virus. Antibodies can be used to prevent secondary bacteria infection. Although there are no specific antiviral drugs used for FVR ganciclovir, PMEDAP, and cidofivir hold promise for treatment. Recent research has shown that famciclovir is effective at treating infection in cats with little to no side effects reported. In severe cases intravenous fluid and oxygen may be necessary.