Upper respiratory infections are a common cause of feline respiratory disease, especially in young kittens. Feline upper respiratory infections are actually caused by a number of different organisms, all of which produce very similar respiratory disease symptoms.
Common Causes of Upper Respiratory Infection in Cats
Viral infections are most commonly implicated in causing feline upper respiratory infections. The most common viral infections diagnosed in respiratory disease in cats are:
- feline calicivirus
- feline herpesvirus 1, also commonly known as feline rhinotracheitis
Though feline herpesvirus and calicivirus account for the majority of cases of upper respiratory disease in cats, there are other organisms that may also be causative. These organisms include:
- Chlamydophila felis, previously called Chlamydia psittaci
- Bordetella bronchiseptica
There may occasionally be other organisms involved in the pathogenesis of feline respiratory infections as well. In addition, affected cats may be infected with more than one type of organism at the same time.
Risk Factors for Developing Feline Respiratory Disease Due to Upper Respiratory Infections
Kittens are the group at highest risk for developing disease resulting from upper respiratory infections because of their immature immune system. They are also likely to exhibit more serious disease than more mature cats.
Cats that are immunosuppressed are at greater risk of developing respiratory disease due to upper respiratory infection. This may include cats suffering from feline leukemia or feline AIDS or cats that are receiving immunosuppressive medications for other disease processes.
Cats that are undergoing stress may be at increased risk at well. Stress may result from sudden changes in the cat’s routine, recently undergoing surgery, addition of a new pet or new family member to the cat’s environment and many other situations.
Persians and other brachycephalic breeds (breeds with a flattened face) may also experience an elevated risk of respiratory disease and upper respiratory infections due to their anatomy.
Cats that are unvaccinated against feline herpesvirus1 and calicivirus are also more likely to become infected and suffer upper respiratory disease.
Symptoms of Feline Upper Respiratory Infection
Cats with upper respiratory infections may exhibit symptoms such as:
- runny eyes
- runny nose
- ulcers (sores) in the mouth and/or nose
- harsh voice
The symptoms and the course of disease will vary depending on which agent is responsible for infecting the cat and causing the respiratory disease symptoms. In general, the course of the disease is usually approximately 7-10 days.
Herpesvirus infections are usually permanent and can be recurrent, often flaring and producing symptoms of upper respiratory disease after a stressful episode such as undergoing a surgical procedure, being introduced to a boarding facility, or having a new family member or a new pet introduced to the household.
Most cases of feline upper respiratory infections are mild and self-limiting and treatment is normally symptomatic. However, in some situations, the respiratory disease can become serious and even life-threatening. Pneumonia is a possible sequelae to upper respiratory infections, especially in young kittens. If the cat stops eating, becomes extremely lethargic, develops a high fever or exhibits an open-mouth breathing pattern, veterinary intervention is required and hospitalization and supportive care may be necessary as a part of the treatment for the upper respiratory infection.
Feline Respiratory Disease and Upper Respiratory Infections
Feline respiratory disease may be caused by many different conditions. However, upper respiratory infections are common causes of respiratory disease in the cat. Kittens are most often infected with these respiratory infections but adult cats may be infected under the right circumstances as well. Treatment is generally symptomatic and, in some cases, respiratory symptoms may be recurrent and may resurface when the infected cat is placed in a stressful situation.