By Dr. Carl Palazzolo, DVM, Long Beach Animal Hospital
Photos courtesy of LBAH.
How does a cat that has been indoors all of its life and not exposed to other cats suddenly look miserable, with reddened, runny eyes; nasal discharge; sneezing and a fever, all due to an upper-respiratory infection?
This type of infection is a result of viruses along with secondary bacterial infections. Cats with these symptoms probably had these viruses all along, passed on to them by their mothers shortly after birth and sometimes before, by crossing the placenta.
Viral infections such as feline herpes virus 1 (FHV-1), along with bacterial infections like chlamydia and mycoplasma, are commonly found in most cat populations. They hide in the cells and nerve fibers of the sinuses and nasal cavities. This population of viruses and bacteria has been living in the nasal cavity and sinuses in a quiescent state, with the cat showing no symptoms. One day, it all becomes active, and symptoms develop. This comes about because of stress and the unique immune system of cats. The viruses cause everything from a mild eye irritation to life-threatening pneumonia.
A veterinarian will listen to the lungs carefully to determine if the upper respiratory infection has spread to the lungs and is now causing pneumonia.
If changes are heard in the lungs, a radiograph is taken to look for pneumonia, along with other problems that can have the same symptoms.
Some cats may never show any signs of disease at all but can be carriers, periodically shedding the virus when it becomes active. Others can get the disease and get over it, only to have it recur. Others can get a low-grade chronic disease that lasts all their life.
Some cats may have high fevers, not eat, and have ulcers in their mouths. These cats need to be hospitalized if they are to recover.
A vet carefully checks the tongue and mouth for ulcers.
Upper-respiratory infection is commonly seen in young cats in times of stress, such as being transported to a new home, being introduced to other cats, or taking up residence in an animal shelter. Their immature immune systems become overloaded with multiple infections such as herpes virus along with chlamydia and mycoplasma. If they also carry a serious systemic virus such as feline leukemia (FeLV) or feline immunodeficiency virus (FIV), these kittens can become so ill that they may not survive.
Cats with severe upper-respiratory infection can become dehydrated. Administering fluids makes them feel dramatically better and helps them fight off the infection.
These combinations of viral and bacterial infection in the conjunctival (area around the eyeball) tissues and respiratory passages can create all kinds of problems, including permanent eye damage, chronic sneezing and nasal discharge. Treating these cats early and aggressively is the best way to help them get over their infections and avoid permanent damage.
Your veterinarian should check the eyes carefully on cat’s with respiratory disease.
If left untreated, a herpes virus can cause permanent scarring of the eyes.
Treatment for conjunctivitis includes topical eye medications given two to three times per day. Oral antibiotics and/or anti-viral medications may help reduce or eliminate the associated respiratory infection. Your veterinarian will let you know which combination of these medications is appropriate for your cat’s problem.