Many cat owners have experienced a “snotty kitty” – your cat doesn’t feel well, sneezes and sounds congested much like a person with a cold. But what causes these infections and how can you help your cat feel better? We asked Dr. Beedle to explain.
What causes the infection?
Feline upper respiratory infections are caused by a variety of highly contagious viruses and bacteria. The main agents of infections are the herpesvirus and calicivirus, together accounting for about 90% of infections. Additional agents are Chlamydophila, Mycoplasma, Bordetella, and other bacteria. A cat can be infected with more than one agent at a time.
How did my cat get infected?
Usually, cats become infected at shelters or from contact with outdoor cats. The viruses are spread by wet sneezes from infected cats, and an uninfected cat must be in the same room or share the same toys/food bowls as an infected cat. Due to their undeveloped immune systems, kittens are predisposed to infection and are usually more severely affected. The herpesvirus can survive for 18 hours outside of the host, but the calicivirus can survive up to 10 days.
It is important to know that both the herpesvirus and calicivirus are permanent infections. They will stay within the cat’s system for life. For the herpesvirus, episodes of stress (such as surgery, boarding, moving, new cat/dog in house, etc.) will cause a flare up of the disease about a week following the event. A cat will then shed the active herpesvirus for another couple of weeks. This is why sometimes in multicat households one cat will get sick, and the other cats will follow shortly after.
The calicivirus can shed continuously (not just in times of stress like the herpesvirus) for several months after the initial infection. However, most cats affected by the calicivirus do not seem to have the same recurrence issues like the cats with the herpesvirus.
Can I get this infection? Can my dog?
No. These viruses are not transmissible to people or to other animals.
What should I look for if my cat is infected?
Active infections will cause sneezing, nasal discharge, runny eyes, cough, oral or nasal ulcers, sniffles, fever, and/or a hoarse voice. In more severely affected cats, you can also see a loss of appetite, severe congestion with open mouth breathing, and lethargy.
How is an upper respiratory infection treated?
First off, start with a visit to your veterinarian. Because the length and severity of the infection depends on the combination of agents involved, your veterinarian will approach treatment depending on a number of factors.
Early Infections – With viral causes to the infection, antibiotics are not initially needed. For early, uncomplicated infections we will often start treatment with a supplement which decreases the herpesviral replication in the body. Then the cat will get over the “cold” like you or I. It just takes a little time. An example of an uncomplicated infection involves sneezing with no discharge from the eyes or nose.
Secondary Infections – Unfortunately, viral infections often lead to secondary bacterial infections with green/yellow discharge from the nose or eyes, and congestion. When these secondary infections occur, antibiotics are required. The antibiotics will be either oral or for the eyes, depending on what body systems are affected. Also if there are oral ulcers from the calicivirus, then pain medication is needed.
Severe Infections – For more severely affected cats, hospitalization may be required. These cats will often be dehydrated, severely congested, anorexic, and may have difficulty breathing. Sometimes in younger kittens, an upper respiratory infection can progress to pneumonia, requiring hospitalization.
Chronic Infections – Occasionally, some cats will become chronically affected with an upper respiratory infection. These cats will always be congested and cough/sneeze. The may also have chronic, mucoid eye discharge. Treatment options for these cats include chronic anti-viral medications (oral or topical for the eyes), nasal sinus flushing, and a nasal vaccine given about every 3 months. The nasal vaccine produces extra immune stimulation to the area where the viral infection is active and may help palliate the signs of infection.
How can I prevent my cat from getting infected?
There is an injectable combination vaccine that protects against both viruses and the feline distemper virus. It does not prevent the cat from getting a herpesvirus or calicivirus infection but will lessen the severity of the diseases.
If your cat has already had a previous upper respiratory infection, reducing stressful events can help prevent flare-ups. Maintaining proper nutrition and parasite control will also help.
If you have multiple cats and one starts having a recurrence of infection, keep that cat isolated from the other cats for 2 weeks to lessen the spread of disease. Also, use a diluted 5% bleach solution (1/2 cup bleach in 1 gallon of water) to sanitize the environment when a cat has an active infection. Also if you adopt a new cat, isolate it from other cats in the house for at least 2 weeks in case an infection develops.