KENNEL COUGH (INFECTIOUS TRACHEOBRONCHITIS) IN DOGS
Kennel cough is a respiratory disease that can affect puppies or adult dogs. It is very contagious between dogs but not contagious to people. Kennel cough is characterized by a harsh, hacking cough that typically is triggered by exercise and is sometimes productive (a small amount of phlegm or stomach contents are coughed up). There may be nasal discharge and sneezing, but other signs such as diarrhea, loss of appetite, and lethargy are uncommon.
Kennel cough is caused by one or more of several different viruses or bacteria. The spread of these organisms is similar to the spread of cold germs in people; just as colds readily spread through schools and workplaces, kennel cough spreads through boarding facilities and dog daycares. We have also had patients who caught kennel cough at the dog park, from one-on-one contact with an infected dog, and from walking in the same neighborhood with an infected dog. Some of our kennel cough patients have no known contact with other dogs.
Dogs with kennel cough have signs of illness that is similar to colds in people. They begin coughing within 2 days to 2 weeks of exposure. The cough is at its worse for about a week, and then it gradually tapers off over the course of another one to two weeks. A small number of dogs will sneeze, reverse sneeze, have nasal discharge, and have conjunctivitis with eye discharge.
More than 90% of dogs recover from their problem without experiencing any complications. Of the remaining 10%, some will develop pneumonia and some will develop chronic bronchitis. If the pet develops pneumonia, the signs usually change from just coughing to coughing along with lethargy and loss of appetite. If chronic bronchitis develops, the dog feels well other than coughing, but the coughing continues beyond 3 weeks.
There is no specific test for kennel cough; it is a "rule-out diagnosis". If, based on the history and physical exam, we can reliably discount other possible causes for coughing we consider the pet's problem to be kennel cough.
Occasionally blood tests, xrays and an ultrasound exam are very helpful in the "rule-out" process.
Dogs that might have developed either pneumonia or kennel cough as a complication of kennel cough require diagnostic tests in addition to the physical exam.
A common treatment is no treatment. As long as the pet is eating and acting well other than coughing, monitoring the pet until the coughing stops is a reasonable option.
If the cough is persistent enough that the dog (or owner) cannot rest then we will use an antitussive and/or cortisone.
Antibiotics are often not needed, but are also not contraindicated. We will use antibiotics if the patient is a puppy, and also if the owner is more comfortable treating their pet with one rather than simply monitoring.
Dogs that develop pneumonia require treatment with antibiotics and sometimes more intensive care; dogs with chronic bronchitis need corticosteroids and sometimes antitussives.
The vaccine for kennel cough provides reasonable protection against one bacteria and one virus. We believe these are the most common causes of kennel cough, but they are far from the only causes, so the vaccine is very worthwhile but some vaccinated dogs will still contract the illness.
Some dogs are asymptomatic carriers - they carry the kennel cough organism(s) and are capable of passing them to other dogs, but they have no signs of their own.
Just as it is impossible to prevent cold outbreaks in daycares and elementary schools, it is impossible to completely prevent kennel cough outbreaks in dog daycare and boarding facilities.
We regularly encounter the question "When can my dog go back to daycare, or be boarded?" when the pet is recovering from kennel cough. Studies have shown that dogs can shed the infectious organisms that cause kennel cough for up to six weeks after they stop coughing. However, the amount of infectious organism that the dog is shedding is greatly decreased by the time it stops coughing, and they then pose a minimal risk to other dogs. Ultimately, though, the decision is up to the daycare or boarding facility.
The prognosis for recovery from uncomplicated kennel cough is excellent. Recovery from complicated kennel cough is fair to good.
Yarmouth Veterinary Center