Cats are susceptible to numerous respiratory illnesses. The most common are infections of the nose, upper airways and eyes. The causes of upper respiratory infections (URI) are viruses and bacteria. Less commonly, these organisms can invade the lower airways (the windpipe and the lungs). Cats also get non-infectious respiratory diseases, such as asthma.
Feline Respiratory Viruses
Two very contagious viruses are to blame for most of the respiratory infections of cats. These are Feline Herpesvirus-1, which causes Feline Viral Rhinotracheitis (FVR) and Feline Calicivirus (FCV), which causes the disease of the same name. Both organisms are readily transmitted through sneezing and contact between cats. They can also be spread on hands, clothing, and inanimate objects.
Signs of FVR include sneezing, runny eyes, nasal discharge that may be thick and green, fever, lethargy, loss of appetite, and drooling. Non-vaccinated kittens and cats often become severely ill and can even die. Signs of FCV are similar, but there are differences. The nasal discharge in cats with FCV is watery. FCV can also cause sores in the mouth, diarrhea, and arthritis. Some cases of FCV progress to pneumonia, but most cats ultimately recover. Although laboratory tests are occasionally used, FVR and FCV can usually be diagnosed based on a physical examination.
Treatment is aimed at reducing symptoms and preventing secondary bacterial infections. Fluids are administered because dehydration is common, especially if the cat is not eating or drinking. Decongestants and antihistamines help with nasal problems. Antibiotics do not kill the viruses, but are prescribed to prevent sick cats from getting bacterial infections. Cats with FCV or FVR also benefit from being kept warm, stress-free, and being spoon fed. Warmed, highly palatable foods are recommended, such as meat flavored baby food, tuna flavored cat food, or veterinary diets designed especially for sick cats. Most cats recover within a week or two.
Its difficult to completely prevent viral respiratory infections, but vaccinations are extremely valuable. Vaccinated cats are less susceptible, and if they do get one of these viruses they usually only have mild symptoms. The combination vaccine given to most cats protects against both FVR and FCV. Keeping cats indoors and avoiding exposure to strays is also beneficial. If you do handle other cats, wash your hands and change any contaminated clothing before handling your own cat. The viruses can linger in the environment for days, but cleaning with diluted bleach will remove them.
Two types of bacteria have been associated with respiratory disease in cats. Chlamydophila felis (previously called Chlamydia psittaci) causes inflammation of the eyelids and runny eyes. It is spread by direct contact between cats and is treatable with antibiotics. A vaccine is available for cats at risk.
Bordetella bronchiseptica causes illness that resembles viral disease, with one important difference. Coughing is uncommon with the other diseases but occurs frequently in cats infected with Bordetella. Bordetella is highly contagious and can be passed between dogs and cats. Bordetella is a serious concern in animal shelters and other places where large numbers of cats are housed. Its significance for individually owned cats is still undergoing research. A vaccine recently became available for feline Bordetella, but it is primarily recommended for cats at high risk, such as those in shelters. Check with your veterinarian to see if your cat would benefit from vaccination against bacterial respiratory illnesses.
Cats get other respiratory diseases too, but they are less common. Feline asthma resembles the condition in humans. Symptoms include coughing, wheezing, and difficulty breathing. Emergency treatment may be needed for acute episodes. Asthma isnt curable but can be managed with medication.
Coughing and difficulty breathing can also be a sign of Heartworm Disease in cats. This usually resolves within one to two years, but there is no treatment. It can occasionally be fatal. Cats can be protected from infection with heartworms by using a monthly medication. Ask your veterinarian whether your cat needs heartworm preventive medication.