OVERVIEW
Feline upper respiratory infection refers to infections in the area of the nose, throat and sinus area, much like the common cold in humans. In cats, these infections are quite common and very contagious. The two primary viruses involved are feline herpesvirus-1 and feline calicivirus. Feline chlamydia, a bacterial infection, can also result in upper respiratory tract infections.

Cats that recover from feline upper respiratory infection will periodically shed the virus throughout their lives in times of stress. It is uncommon for the cat to have a reoccurrence of the upper respiratory infection but they are considered a reservoir for the virus. These viruses do not live long in the environment and are easily killed by household cleaners, such as bleach. Unfortunately, unsuspecting owners can carry the virus from an ill or viral-shedding cat to their homes. This is a common way that feline upper respiratory infections are transmitted.

WHAT TO WATCH FOR
Sneezing
Watery eyes
Nasal discharge
Lack of appetite
Drooling
Breathing problems
Open mouth breathing

Cats susceptible to upper respiratory infections generally develop early signs about two to five days after exposure. Fever and sinus congestion may also occur. The disease typically resolves in 10-14 days, without complications. Be on the alert for complications such as lack of appetite due to poor smelling ability, pneumonia, eye ulcers or mouth sores. Very young kittens have a higher incidence of pneumonia and some do not survive the infection.
DIAGNOSIS
Diagnosing feline upper respiratory infection is generally based on physical exam findings and typical symptoms of fever, congestion, sneezing, watery eyes, nasal discharge and occasionally drooling. Finding the exact viral or bacterial cause of the infection, however, is more difficult, and your veterinarian may not want to pursue it. Some diagnostic tests might prove helpful, however, such as nasal or throat swabs, blood tests to determine the overall health of the cat, and chest x-rays to detect pneumonia.
TREATMENT
Since most upper respiratory infections are viral, there are no drugs available to kill these viruses so treatment is aimed at treating the symptoms and maintaining your cat’s overall health to bolster the immune system and help speed recovery. Basic treatment usually includes proper diet and sufficient fluids, antibiotics, nebulization (a process to humidify the air and keep the nasal passages moist), and eye medication if eye ulcers are present. If your cat does not respond to treatment at home, hospitalization may be necessary.
HOME CARE
If your cat is treated at home you will need to provide care that includes keeping the nose and eyes clear of discharge. Administer all medications your veterinarian prescribes and provide sufficient food and fluids so your cat does not become dehydrated. Keep your cat away from other cats until fully recovered or even longer due to the potential for viral spread.
PREVENTATIVE CARE
The best way to prevent upper respiratory infections is to follow the vaccination procedures by your veterinarian. Vaccines can be administered by two methods, intranasal method and injection. Also, keep your cat away from other sneezing, ill cats and take precautions when introducing a new cat to the household.

INFORMATION IN-DEPTH
Feline upper respiratory infection refers to infections in the area of the nose, throat and sinus areas. It is caused by two major viruses: Feline Herpesvirus-1 and Feline Calicivirus. Feline Chlamydia, a bacterial agent, also results in upper respiratory symptoms. Distinguishing among these three can be difficult, so it is not usually done.

Feline upper respiratory infection is very contagious. Cats at most risk include young kittens, unvaccinated cats, elderly cats and cats that are kept in close quarters with other cats such as shelters, catteries and even multi-cat households.

The viruses and bacteria involved in upper respiratory infections do not live very long outside of the infected cat. The disease is transmitted by a variety of methods:



Direct contact with an ill cat.


Contact with the virus through sneezing (sneezing can propel the virus or bacteria up to 4 feet away).


Contact with the virus on human clothing, food bowls or hands. Large amounts of the virus are present in the saliva, tears and nasal discharges.


Contact with a cat that is a carrier of the virus. Most common is a nursing carrier queen transmitting the infection to her kittens around the time of weaning.

VETERINARY CARE IN-DEPTH

DIAGNOSIS
After exposure, incubation lasts from two to five days. Sneezing is usually the first and sometimes the only sign observed. Other signs include congestion, eye and nasal discharge and fever. Bacterial pneumonia, a serious complication most frequently seen in young kittens, often develops.

Despite having very similar signs of infection, feline herpesvirus-1, feline calicivirus and feline chlamydia have some signs that are specific. Being familiar with these signs may help with diagnosis.


Feline Herpesvirus-1 infection is likely to cause corneal ulcers.


Feline Calicivirus infection is likely to cause mouth ulcers.


Feline Chlamydia infection is likely to cause mild upper respiratory signs, primarily significant eye discharge and conjunctivitis.

However, eye ulcers, mouth ulcers or profuse eye discharge do not always occur. Consequently, the exact cause of the upper respiratory infection may never be identified.

Your veterinarian may wish to perform some diagnostic tests to determine the overall health of your cat as well as the response to the treatment. Some of these may include:


Complete blood count (CBC) to evaluate red blood cells, platelets and white blood cells. This can help your veterinarian determine how the body is responding to the infection.


A blood chemistry profile and urinalysis to evaluate the overall health of the cat.


Feline leukemia and feline immunodeficiency virus testing to rule out leukemia and AIDS. These viruses can weaken the immune system and make your cat more susceptible to upper respiratory infections.
TREATMENT
Because of the contagious nature of the disease, your cat will probably be treated on an outpatient basis and will likely begin to feel better in 10-14 days. Some cats show great improvement in just five to seven days. Since there is no specific treatment aimed at destroying the virus, treatment is aimed at maintaining the overall health of your cat and making him feel better.


Diet. Because of congestion, your cat may have difficulty smelling food and might refuse to eat. Offer a variety of aromatic diets or warm the food to help increase the smell and encourage eating. If your pet does not eat enough, you may have to administer liquid or soft food with an oral syringe. The amount of food your cat will need each day is based on his current appetite and weight. Your veterinarian can give you guidelines on how to offer food with a syringe and how much to offer.

There are also medications available to help stimulate the appetite. Your veterinarian may prescribe cyproheptadine. Diazepam (Valium®) has been used in the past but it not currently recommended due to potential liver toxicity. Your cat may also need supplemental potassium or vitamin B complex.


Fluids. Your cat may also refuse to drink and can easily become dehydrated. You can offer fluids by syringe but this usually is not sufficient. Your veterinarian may want to administer fluids subcutaneously.


Decongestants. If your cat has significant nasal congestion, he may benefit from Afrin®, a nasal decongestant. Placing one drop in each nostril twice daily can help reduce some congestion. However, most cats do not tolerate this very well.


Antibiotics. Your veterinarian will likely prescribe antibiotics in order to prevent secondary bacterial infections. Most commonly used are doxycycline, amoxicillin, Clavamox®, and cephalosporins.


Eye ointments. Your cat may suffer from eye problems such as excessive discharge or corneal ulcers. Typically, tetracycline based ointments work well to alleviate this problem. Antiviral eye ointments are also available, but because of high cost, these are reserved for use in severe cases.


Hospitalization. If your cat has severe symptoms or doesn’t respond to outpatient treatment, he may need to be hospitalized, where he can receive intravenous fluids and frequent nebulization. This is a process to humidify the air and keep nasal passages moist. A temporary feeding tube may also be needed if your cat is unwilling to eat and resistant to syringe feeding.

HOME CARE AND PREVENTION
Due to the contagious nature of this illness, many cats are not hospitalized unless significant complications, such as pneumonia, occur. While your cat is at home, you will need to provide the following care:



Keep the nose and eyes clear of discharge. Gently wipe any discharge with a warm, damp towel.


Administer all medications as your veterinarian prescribes, even if your cat seems to be feeling better.


Monitor your cat’s appetite and provide baby food, canned cat food or warmed food to increase the smells to entice the cat to eat. If your cat is not eating, consult your veterinarian. Some cats will need temporary feeding tubes until the congestion clears.


Keep your cat indoors and away from other cats. Remember that feline upper respiratory infection is highly contagious. Treating one ill cat is time consuming and difficult enough; you don’t need to add additional ill cats to your family. Unfortunately, despite all your efforts, other cats in the household may develop the disease.

The best way to prevent upper respiratory infections is to follow the vaccination procedures recommended by your veterinarian. Vaccination can significantly reduce the potential for infection in cats that have not previous been exposed to the virus. Unfortunately, vaccination does nothing to eliminate the carrier status of previously infected cats and it does not prevent viral shedding.

Vaccines are administered by two methods: intranasal and injectable.


Intranasal vaccination has a more rapid onset of protection than the injectable but the cat may develop sneezing and nasal discharge for a few days after administration.


Injectable vaccination has fewer side effects but a slower onset of protection. Also, injectable vaccines carry the potential for injection site sarcomas.

Keep your cat, and yourself, away from other sneezing, ill cats.

CARRIERS
Most cats that recover from upper respiratory disease become “carriers.” Your cat may show no signs of the disease, but may shed the virus in saliva, tears and nasal secretions, and become a source of infection to other cats. Recurrence is also possible, especially in times of stress, even without exposure to an ill cat. Introducing a new cat to your home can result in an upper respiratory outbreak. Keep in mind, even cats that appear healthy when adopted may be carriers.