UPPER RESPIRATORY INFECTION IN CATSCategory: Respiratory
Upper respiratory infections in cats are most commonly caused by feline herpes virus-1 (FHV-1), feline calicivirus (FCV) or the feline strain of Chlamydia psittaci, which is a bacterium. There are other viral and bacterial pathogens that less commonly cause upper respiratory infection in cats.
The clinical signs of upper respiratory infection in cats include anorexia, depression, fever and oculo-nasal discharge (from the eyes and nose). With feline herpes virus-1, we see sneezing, clear to green oculo-nasal discharge, cough, hypersalivation (lots of slobber) and loss of voice. In some cases, corneal ulcers are seen as well. Feline calicivirus infection often leads to oral ulceration, mild sneezing and conjunctivitis. With Chlamydia psittaci, ocular signs predominate and include thick, greenish ocular discharge on one or both sides. Mild sneezing, nasal discharge and coughing can occur.
These organisms are highly contagious and transmitted by direct cat to cat contact or by contaminated cages, grooming tables, water and food dishes and human hands. Cats from shelters, pet stores and multi-cat households are the most frequently infected individuals. Feline herpes virus-1 is fragile, surviving only 18-24 hours outside the cat. Feline calicivirus is a very tough virus and may survive outside of the cat for 8-10 days. The preferred disinfectant for the organisms is a 1:32 solution of bleach.
Feline respiratory infections are serious and should be seen by the veterinarian. Viral upper respiratory infections are usually self-limiting and resolve on their own in 5-7 days, but we still treat with antibiotics since it is often difficult to discern between viral and bacterial disease. In addition, inflamed tissue is very susceptible to secondary bacterial infections. Treatment most often includes an injection of antibiotics, oral antibiotics and topical medications for the eye. In cases involving cough and sneeze, we often use medications to control these symptoms. In severe cases, hospitalization and IV fluid and antibiotic therapy are necessary. Cases with severe ocular involvement also require specialized therapy.
Feline respiratory infection is by and large prevented with regular vaccination. Yearly vaccines contain antigen for feline herpesvirus-1, feline calicivirus and Chlamydia psittaci.