These infections are spread through direct dog-to-dog contact, as well as inhalation of aerosolized respiratory droplets and contact with contaminated objects and surfaces (such as shared food bowls and toys.) Transmission most commonly occurs in places where dogs from different households come into contact with one another, such as dog parks, boarding kennels, doggie daycares, grooming facilities, and dog shows. The incubation period varies from 2 to 10 days, depending on which pathogen is present.
The most common sign of “kennel cough” is episodes of a harsh, dry, hacking cough. These episodes often end with a gag or retch, and it may sound as though there is something caught in the dog’s throat. Nasal discharge and sneezing may also be noticed. Usually affected dogs still have a normal appetite and energy level. It is important to remember that an infected dog is contagious to other dogs from the time they first show signs until up to two weeks after they stop coughing, and they should not go anywhere where they are likely to encounter other dogs during this period.
Most cases of “kennel cough” will resolve on their own within 10 days, although complications such as pneumonia occur in a small percentage of dogs—usually in young puppies and dogs with weakened immune systems. Loss of appetite, lethargy, fever, and difficulty breathing are all potential signs of secondary pneumonia, and if any of these signs develop, the dog should be examined by a veterinarian as soon as possible so appropriate treatment can be started.
The most important thing you can do to reduce your dog’s risk of getting an upper respiratory infection is to get them vaccinated against the respiratory pathogens for which vaccines exist. The Bordetella vaccine, canine influenza vaccine, and DHPP vaccine (which includes adenovirus and parainfluenza) will all provide protection against their respective pathogens. Because vaccinated dogs will still be vulnerable to the other potential causes of infection, it is also a good idea to temporarily avoid high-risk areas if you hear of an outbreak of “kennel cough” in the area.