Kennel cough is caused by a combination of highly infectious viruses and bacteria that can spread in the air or by direct contact among dogs in the right conditions. It usually presents itself with a few days of being off colour, then a retching cough that starts whenever the dog gets excited or exercises.
The cough usually results in the production of mucus. Generally healthy dogs are not too ill; they may have a mild temperature and may be a little off their food. The cough will get worse over the first few days then, if untreated, gradually go over a week or so. The dog can remain contagious for sometime after symtoms disappear. In very young or old dogs, or if there is concurrent disease, kennel cough may become more severe and lead to a secondary infection. This is very nasty and uncomfortable for the dog.
Dogs can catch kennel cough in several ways. It can spread through the air, directly from dog to dog, or through germs on contaminated objects. It is often spread in enclosed areas—while boarding in a kennel or through direct contact while sitting in a veterinary clinic, training class or dog-grooming facility. Kennel cough is so contagious that your pet might even catch it from sharing a water dish, sniffing the same patch of grass or by simply greeting another dog.
The virus is inhaled as an aerosol which causes inflammation and damage to the the windpipe and allows the bacterial part of kennel cough to manifest. The effects of the bacteria results in irritation of the wind pipe and therefore the cough. Unfortunately the more the dog coughs, the more damage will occur to the airway, in severe coughing cases the animal’s defences are so poor that there is a chance that bacteria will reach the lungs and a pneumonia will begin.
The dog will usually start coughing a four or five days after coming into contact with the virus. Once the cough is there it is important not to do anything to exacerbate it such as strong exercise.
As said before the dog will be very contagious so do not walk them in public places where they will spread the bacteria. If you have more than one dog by the time the cough is evident, all of your dogs are likely to have been exposed. This usually means that all the dogs will become infected, however in some cases, like people with colds, the odd dog will be lucky and miss out.