Bordetella is not particularly common in the average pet cat but can be a significant problem where a number of cats live in close contact particularly in breeding establishments and catteries. It is very easily spread from cat to cat. It is rarely fatal, but can be a real problem because the symptoms may be very difficult to clear up. Prevention is far better than cure – if your cat needs protection make sure she is fully protected by regular vaccinations.

Bordetella bronchiseptica (Bb) is a bacterium closely related to Bordetella pertussis, the cause of whooping cough in humans. Bordetella is one of the bacteria involved in cat flu and kennel cough in the dog. It usually causes most problems when infection occurs at the same time as infection with one of the cat flu viruses (feline herpesvirus and feline calicivirus). If one of the viruses gets hold then your cat’s immune system may be so busy fighting it that other bugs (particularly bacteria) will also join in the attack.

Although the respiratory viruses (herpesvirus, calicivirus) remain the most common cause of cat flu, research has recently shown that Bordetella bronchiseptica (Bb) can also cause flu in its own right.

Rather like human ‘flu’, cat flu is spread by droplets of moisture containing the virus passing from cat to cat, through sneezing, direct contact or sharing food bowls. Infected cats can spread the virus in saliva and nasal discharges (snot). The incubation period (the time for which a cat is infected and carries the disease before the symptoms develop) is up to 3 weeks.

Around 1 in 10 cats in the UK has Bordetella. This means that it is quite possible for your cat to pick up the disease from another cat that seems healthy. It is also possible for people to spread the disease from cat to cat when handling them.

The signs of cat flu are very obvious and unlikely to be mistaken for anything else. In fact cat flu is often very similar to human flu starting with a high fever which may make your cat feel miserable and off her food, followed by the sneezing, coughing and sore eyes. Signs usually start to get better after about 7 days and, in most cases, your cat should be back to her old self in about 2-3 weeks. Bordetella can cause pneumonia and if your cat is suffering from flu and you are not happy with her progress ask your vet to check her again. Young kittens with Bordetella may die before showing any particular signs.

There have been reports of dogs and cats in the same household suffering from infection with Bordetella at the same time. However, there is no evidence that the infection can spread from cats to humans.

There is no treatment for viral infections that are the primary cause of flu in cats. Your cat will have to fight off the infection by herself and fortunately most, otherwise healthy cats, will do this within a few weeks. But cats, just like people, feel pretty miserable when they have the flu and plenty of nursing care is needed to help her get over it. You should always have your cat checked by your vet, and they will prescribe antibiotics if they think bacterial infections, like Bordetella, are present.

Make sure your cat has somewhere comfortable and warm to lie and be sure she gets plenty of water or milk to drink. Although your cat may not want to eat for the first few days, you should try to tempt her to eat by offering tasty warm food to keep her strength up. If your cat is very congested try putting her in a warm steamy environment (like the bathroom with a hot shower running) to ease her breathing. Always keep in close contact with your vet and let him know immediately if your cat appears to take a turn for the worse.

If you have other cats living in your house take particular care to keep them away from the sick cat and always wash your hands after handling her. However, because she will have been infectious before the symptoms developed, it is likely that your other cats will already have been exposed to the disease and may develop symptoms.

Most fit young cats will recover from flu after a few weeks – although in a few cats that do get over the initial illness the problem never really goes away. These animals may be left with persistent problems such as runny noses. Sometimes these cats are on almost permanent medication to control their symptoms. The disease can be much more serious in young kittens, older cats and cats with other diseases, e.g. FeLV or FIV – these patients may need to be admitted to hospital for special treatment but, even so, may not survive.

Safeguarding against Bb should be considered with specific protection for those most at risk and few are more at risk than kittens in breeding colonies and rescue shelters.

A vaccine that protects against Bordetella is available. The vaccine is administered as drops into the nose and provides protection within 72 hours. This vaccine is not routinely given to pet cats and you would need to discuss with your vet whether your cat needed this additional protection. Many catteries require that cats are vaccinated against Bordetella before being boarded.

Bordetella can also cause kennel cough in dogs. If your dog has a cough keep your cat away from them.