Cat Flu

What is it? What causes it? Should I adopt a cat with cat ‘flu?

What is Cat Flu?

Cat flu is a disease, much like human flu, that can be caused by a number of different viruses (Calici virus and  Herpes virus). There are other diseases that are caused by different organisms that can be confused with cat flu ( Bordetella bronchiseptica and Chlamyophila felis).

Cat flu is not always serious in healthy cats but it can be serious , even fatal, in kittens and adult cats with underlying illnesses.

Symptoms of cat flu

  • Runny eyes and nose
  • Sore throat
  • Mouth ulcers
  • Dribbling
  • Sneezing
  • Loss of voice
  • Fever

Cat Flu Treatment

If you think that your cat has cat flu, you should contact the practice. There are some medications that will help your cat to feel a little better, but there is no specific ‘cure’ for your cat. Just as if you have the flu, the treatment is aimed at controlling the signs of illness and helping to improve your cat’s appetite.

It is possible to find out which virus is causing the illness, but in most cases this is not necessary as the treatments are general. If your cat is very poorly and unable to eat at all, hospitalisation may be necessary.

The sort of treatments used may be anti-inflammatories (NEVER GIVE YOUR CAT PARACETAMOL as it is VERY TOXIC to them), lubricants and eye drops and possibly antibiotics (if your cat is showing signs of a secondary bacterial infection). There are some anti-viral treatments available, though they can be very expensive and are not always effective.


Prevention is better than cure and a vaccine is available. This is usually started with a primary course of two injections three weeks apart when your cat is a kitten. As an adult, you cat will require a booster EVERY year to keep them protected. It is important to remember that your cat will need to be fully up to date with vaccinations before they can go into a cattery when you are on holiday.

No vaccine gives complete protection but it is still worth vaccinating your cat as it’s the best preventative measure. It may also help to reduce symptoms if they do become infected. The vaccine cannot prevent symptoms from occurring if the animal already has cat flu.

It is important to know cats with cat flu can become carriers of the disease. This is still the case with vaccinated cats but they are less likely to catch the disease in the first place.

Cat Flu in Kittens

Kittens get some immunity from their mother which fades as they get older. Mum cats with cat flu can also infect their own kittens without showing signs of illness themselves because of the possible carrier status. The kittens either get flu or become symptom free carriers.

Looking after a Cat with Cat Flu

In most cases you will be able to care for your cat at home. This is much the best place for your poorly cat as they will be less stressed.

  • Reduce Stress. Stress can make your cat’s illness worse.
  • Wipe Nose and Eyes. Wipe away discharge from the eyes and nose regularly using a cotton wool pad soaked in warm water. This will enable them to feel better, smell their food better and help them to breathe easier.
  • Keep the Fed and Hydrated. Cats can easily become dehydrated when they have cat flu because they lose their sense of smell and taste. This tends to make them eat and drink less. You can help by feeding them foods that are easy to eat (soft foods) and have strong smells (sardines, pilchards, roast chicken, tuna). It is also important to encourage them to drink as this helps to loosen the mucus that tends to build up in the back of the nose and throat. Flavouring their water can be helpful to tempt them.
  • Help them Breathe. Steam may help to loosen mucus in their airways so you could try letting your cat in the bathroom when you have a shower or bath. However, be careful to look out for any signs of stress and remove your cat from the room if they look worried.

The Cat Flu Viruses:

Calicivirus. The calicivirus exists in lots of slightly different forms called ‘strains’. Vaccination against calicivirus is difficult because the vaccine canno cover all the strains, so it’s not fully protective. Calicivirus can cause mouth ulcers as well as lameness in young kittens. Many cats will recover and are no longer contagious after one or two years.

Herpes Virus. This virus is often more severe and is more likely to produce eye ulcers. The virus has only one strain, so vaccination against it works better. Following infection with Herpes virus, it is thought that all cats become carriers. They produce the virus in their tears, saliva and nose flid, but only every now and then. This means that swabs taken from these cats will not always detect the virus. Cats that are carriers remain so for life.

Cat Flu Carriers

Following infection, many cats are left as carriers, which means they do not have many/any symptoms but can potentially infect others. Some carrier cats occasionally have a runny eye or nose for a few days. Recurrences of flu can follow stressful events, such as a visit to the cattery or vets or the arrival of a new cat in the house.

Others are unlucky and are left with a permanent, lifelong, thick, runny nose (chronic rhinitis). This happens because the delicate nasal lining has been damaged, allowing repeated bacterial infections for which antibiotics may only provide temporary relief.

It’s thought that flu viruses, especially calicivirus, may contribute to long-term inflammation and soreness of the mouth (gingivitis or stomatitis). This is a complicated condition which is often difficult to cure. Calicivirus may not be the only cause. Longterm drug treatment is often needed for control and in some cases, extraction of the teeth may be needed.