Introduction

Infectious canine tracheobronchitis, more commonly known as kennel cough, is a highly contagious, acute upper-respiratory tract disease complex that occurs in dogs. Fortunately, the signs of kennel cough are easy to recognize. If a dog exhibits these signs, particularly if it has recently been boarded, to a dog show, to the dog park or otherwise exposed to a number of dogs in close quarters, the dog’s owner should take it to the veterinarian as soon as possible.

Symptoms of Kennel Cough

Most dogs with kennel cough show a classic course of mild disease characterized by one or more of the following signs:

• Sudden onset of a deep, dry, harsh, hacking cough, without any other signs of illness or discomfort
• A cough that sounds like the dog has “something stuck in its throat” or is choking
• An unproductive cough
• Fits of coughing, especially after exercise
• Gagging, especially after coughing or exercise
• Retching, especially after coughing; frequently accompanied by a white, foamy mucus
• Possible change in the dog’s bark
• Dog is bright, alert and responsive
• Dog has a good appetite

The signs of kennel cough normally appear about 4 to 7 days after exposure to an infected dog, which usually occurs in a high dog-density boarding or other situation, where dogs congregate in what might be less than ideal sanitary or hygienic conditions. Otherwise, most dogs with kennel cough are clinically normal.

In some cases, and more so in puppies or unvaccinated adult dogs, kennel cough can progress to involve more severe secondary respiratory tract infections that include bronchopneumonia and rhinitis. When a dog with kennel cough develops secondary bacterial infections, it may develop one or more of the following symptoms:

• Fever (usually low grade and fluctuating)
• Nasal discharge (runny nose)
• Ocular discharge (runny eyes)
• Deep, moist, productive cough
• Weakness
• Exercise intolerance
• Difficulty breathing (respiratory distress; dyspnea)
• Lethargy (tiredness)
• Depression
• Decreased appetite (inappetance; anorexia)
• Weight loss

While the symptoms of uncomplicated kennel cough may not seem particularly serious, the infection is highly contagious and therefore should be treated immediately.

Dogs at Increased Risk

Dogs of any age are at risk of developing kennel cough, but puppies from 6 weeks to 6 months of age, and unvaccinated or adults with compromised or weakened immune systems, tend to be more frequently and more severely affected. Puppies acquired from commercial pet shops or so-called “puppy mills”, and those coming from shelters, are also more likely to develop kennel cough. There is no gender or breed predisposition to developing kennel cough.