What is Feline Upper Respiratory Infection?

Upper respiratory infections affect the nose, throat and sinuses and are very contagious.  In the majority of cases, they are caused by two viruses, feline calicivirus and feline herpesvirus or, less commonly they can be caused by a bacterial infection.

What are the symptoms?

Symptoms will differ depending on the virus or bacteria causing the infection, but the early common signs to look out for are:-

• Sniffing
• Runny nose
• Sneezing
• Clear discharge from nose and eyes
• Lethargy
• Fever
• Loss of appetite

It is important to get your cat treated as soon as signs of an infection appear.  If your cat develops a secondary bacterial infection, symptoms become much more severe and can be fatal. As the infection progresses your cat will start to develop additional symptoms such as:-

• Thick yellow discharge from nose and eyes
• Wheezing
• Coughing fits
• Nasal congestion causing them to breath open mouthed
• Nasal and mouth ulcers
• Refusal to drink
• Dehydration

What are the causes?

In most cases an upper respiratory infection will be caused by the viruses feline calicivirus (FVC) and feline herpesvirus (FVR/FHV-1).  FVC normally causes a milder infection to the more severe symptoms seen with FVR.  The bacteria Chlamydia and Bordetella are also causes.  If infections go untreated cats can often develop a secondary bacterial infection which can prove fatal.

A virus can be transmitted directly from cat to cat through sneezing, coughing and grooming or from indirect contact by sharing food bowls, water bowls and bedding.  Cats are especially susceptible to catching an upper respiratory infection if their immune systems are already weakened by illness or stress.  Many cats infected with FVC and/or FVR will remain infected carriers for a few months after symptoms stop, and in some cases for life.  This can result in the infection and symptoms resurfacing at times of stress.

What are the risk factors of catching an upper respiratory infection?

Cats who have not been vaccinated and those with a weakened immune system are most at risk of catching an upper respiratory infection if they come into direct contact with other cats. This can occur if they are outdoor cats, free to come and go from the home or are living in crowded, unsanitary environments. The majority of cats who have been exposed to FVR and/or FCV will become life long carriers of the virus even after they have recovered from the infection and show no signs of the condition. Not only does this put unprotected cats around them at risk, it also makes them susceptible to falling ill again at times of stress.

A female cat can be particularly susceptible to catching an infection while pregnant and during lactation, as are their kittens if they are kept around adult cats that have not been vaccinated.

Diagnosing upper respiratory infections

The symptoms exhibited by your cat will often be enough for your vet to make a diagnosis of an upper respiratory infection.  It is likely that they will still want to run several tests to determine the cause of the infection, rule out any other illnesses and to assist with treatment.

Treating upper respiratory infections?

If your cat’s symptoms are fairly mild, and they are well enough to be treated at home, your vet will advise you on how to best make your cat comfortable. Expect to be advised on how you can encourage them to eat and keep them from becoming dehydrated.  You should also be shown how to keep your cat’s eyes and nose clear of discharge.

If your cat is very poorly and there are concerns about them being dehydrated, your vet may advise that your cat be hospitalized for a day or two and be placed on a drip.

In most cases, the vet is likely to prescribe antibiotics to treat or ward off any bacterial infection and medication to boost their immune system.

How can I prevent my cat from developing an upper respiratory infection?

There is a vaccine available to protect your cat from catching the most common viruses (FVR and FVC) and is strongly advised.  Once vaccinated it is important to keep boosters up to date.

If you have more than one cat, regularly disinfect shared items such as food bowls, litter trays and bedding.

When introducing a new cat into your home try and keep it isolated from other cats for the first couple of weeks and kittens should not be introduced to other cats until they have received their inoculations.