A common disease of cats is upper respiratory disease. The symptoms can include but usually do not have all of these; sneezing, nasal discharge, runny eyes, cough, oral or nasal discharge, sniffles, fever, hoarse voice.
The cats that are at risk are cats from a shelter , outdoor cats and kittens. Persian cats are more predisposed to worse signs because of their flat faces. Kittens are more likely to be at risk because their immune systems are immature. The average house cat that is not exposed to other cats and does not go outside is unlikely to get the infection. Most cats are at a low risk. A common scenario is a new kitten from a shelter can bring the infection home to the adult cat.
The cause of upper respiratory infections in cats is either the Feline Herpes Virus or the Feline Calicivius in 90 % of the cases. The bacteria Clamydia is the cause in 10 % of the cases or less. Your veterinarian vaccinates for both the two viruses and the bacteria in the routine vaccines given to cats. The vaccine is effective, but not 100 %. These viruses are not transmissible to people. Cats that are infected with these two viruses are infected for life and the herpes virus can relapse when the kitty is under stress.
Most of the time the symptoms are very mild, but some cats can become very ill. If the cat stops eating or drinking, it can become dehydrated and may need fluid therapy or hospitalization. Some cats can get ulcers on their eyes, nose or mouth. Some can get high fevers or pneumonia. In most outbreaks, you will need to bring your cat in to see your veterinarian.
Even though most of the infections are viral for which usually antibiotics do not help, your veterinarian will prescribe antibiotics in most cases. This is to help prevent secondary bacterial infections which are common. The Chlamydia bacterial infections need to be treated with an antibiotic called doxycyline. This antibiotic can rarely cause staining of the teeth in young animals and so is used with care in those kittens that need it. Sometimes antibiotic eye ointments or viral ophthalmic ointments are used. An amino acid, lysine taken orally can sometimes be helpful for chronic infections and or relapses. At times, kittens need to grow older before they can fight off the infection as their immune systems mature.