Kennel Cough in Dogs: Causes, Facts, and My Experience
Kennel Cough or Canine Infectious Tracheobronchitis
Kennel cough is an unpleasant and very infectious disease in dogs which periodically occurs in outbreaks. The main symptom of the disease is a hacking cough. It’s generally not a serious illness but occasionally leads to pneumonia. This article was prompted not only by my interest in the biological basis of the illness, but also by the fact that my dog recently experienced kennel cough. Misha had a severe case of the disease which was very tiring for him when it was at its worst.
Kennel cough is also known as canine infectious tracheobronchitis or as Bordetella, after the bacterium that is a common cause of the disease. An outbreak may develop after dogs have been in a crowded or stressful situation, such as in a dog daycare facility, a kennel, or a shelter. Poor ventilation increases the risk of infection in a crowded area. Chronic stress can compromise a dog's immune system.
The disease is also transmitted in places that aren't crowded and in situations that aren't stressful. Only a single infected dog is needed to spread the illness. Misha interacts with other dogs that we meet on walks and with his canine companion at home, but he hasn’t been present in a crowd of dogs for a long time.
Any dog with a persistent or recurring cough needs to be checked by a veterinarian. A cough is a common symptom in many diseases.
Possible Symptoms of Kennel Cough
Symptoms of kennel cough don't appear immediately after transmission of the causal agent. The incubation period for the disease is said to be three to ten days, or possibly as long as two weeks in some cases.
Misha's symptoms flared up quite suddenly. He had an occasional cough before this time, but it was so uncommon that I didn't think anything of it. In hindsight, I realize that it may have been the first stage of his illness.
Misha eventually developed the typical symptoms of the disease. His frequent coughs were strong enough to produce gagging and at one stage the release of fluid from his mouth. On one occasion he threw up a small amount of the food that he had eaten as he coughed. Apart from the coughing and the problems that it caused, however, he seemed to feel fine. Vets say that this is generally the case for dogs with kennel cough.
Misha's appetite remained excellent during his illness and he was interested in things happening around him, as always. He even continued to "smile"—a term I use for the happy expression and wagging tail that I often see as I speak to him and stroke him. The smiling stopped when a coughing fit developed, though, as it frequently did when the disease was at its worst. The coughs were obviously very unpleasant.
Misha's coughs were more common when he was active. During this time, the coughs occurred for long periods and as often as every few seconds. In contrast, they occurred for short periods and were less frequent when he was lying down. Misha coughed during the night as well as the day, which interrupted his sleep (and mine). He was noticeably sleepier than usual during the day.
Some dogs develop additional symptoms of the disease, including sneezing and a runny nose. Some develop a fever or mild loss of appetite. Misha didn't experience any of these symptoms, however.
The video below gives a good approximation of the hacking sound and gagging behaviour that Misha exhibited. The narrator is a vet. It's probably a wise idea to check with your own vet about the advisability of giving your dog the human medicine mentioned at the end of the video, though. You should also ask the vet about the correct dose for your dog.
A Demonstration of the Main Symptom
Misha's vet said that kennel cough is often not treated and the dog's immune system is left to cure the disease on its own (although he did decide to treat Misha). Other references agree that the disease is frequently left untreated. It's very important that a dog with a persistent cough is checked by a vet, however, because the condition may not be kennel cough. This is important even if the dog has been in a situation where an outbreak of the disease has developed. Assuming that a sick pet has developed kennel cough during the outbreak and that no treatment is needed could be dangerous for the pet. Even if your dog is behaving like the ones in the video above or below, you shouldn't make assumptions about the cause.
Pneumonia, influenza, and heart disease are examples of diseases that can cause recurring coughs in dogs. Misha's vet checked his lungs and heart very carefully before making a diagnosis of kennel cough. After listening to my description of the situation and hearing Misha cough repeatedly during the visit, the vet diagnosed a severe case of the disease and prescribed antibiotic tablets for him.
Kennel cough is so infectious that a special procedure had to be used for me to see the vet. Instead of entering the clinic and sitting in the waiting room with Misha, I had to wait in the car in case he had kennel cough (after telling the receptionist that I was there). The vet came to get me when he was ready so that I could take Misha straight into the consulting room. After the consultation, I took Misha straight back to the car and then returned to the clinic to pay and to pick up his antibiotic.
Another Dog With Kennel Cough
Sources either say that humans can't get kennel cough or that the disease is very rare in humans. Some say that it only appears in people whose immune system has been compromised, such as those infected by the HIV virus. Cats can get the disease, although they experience it much less frequently than dogs.
Bordetella and Other Causes of Kennel Cough
Bordetella bronchiseptica is a common cause of kennel cough. It's a close relative of Bordetella pertussis, which causes whooping cough in humans. B. bronchiseptica has a rod-shaped cell, as shown below. The cells are airborne but can also be transmitted via objects, such as contaminated water bowls, food bowls, and dog toys.
The bacterium affects the trachea (windpipe) and upper bronchi of a dog. The trachea leads to two large tubes, or bronchi, one going to each lung. The trachea and the bronchi of an infected dog are irritated by the presence of the bacterial cells and become inflamed. Inflammation involves increased blood flow, redness, swelling, and discomfort or pain.
Certain viruses can also cause kennel cough. Researchers say that the cause of the illness is often a mixture of Bordetella and other organisms. The other organisms may include the parainfluenza virus, canine adenovirus type 2 (CAV-2), and a bacterium named Mycoplasma. Mycoplasma is an unusual bacterium because it lacks a cell wall. The listed organisms can also cause kennel cough on their own. Other microorganisms are also thought to contribute to or cause kennel cough.
Antibiotics work against bacteria but not viruses. Without a lab test—which Misha didn't receive—the causative agent of a particular case of kennel cough isn't known. The lack of a lab test to diagnose kennel cough seems to be common, however.
Even though kennel cough may be caused by a virus, antibiotics are sometimes prescribed to attack not only the possible bacterial cause of the disease but also any secondary bacterial infections that develop. A "secondary" bacterial infection is one that develops after the body is in a weakened state due to the effects of an organism such as a virus. The immune system may be less successful in attacking a new invader in this situation.
Misha's medication—Clavaseptin—contained amoxillan and clavulanic acid. Amoxillan is an antibiotic. Clavulanic acid is not an antibiotic, but it improves the function of amoxillan. Some bacteria secrete enzymes known as beta-lactamases. These destroy the structure and activity of some important antibiotics, including amoxillan. Clavulanic acid breaks up beta-lactamases so that they can't inhibit the antibiotics. A combination of amoxillan and clavulanic acid is also used as a human medication. Clavaseptin is prepared for veterinary use, however.
A vet will probably have some suggestions to make an infected dog feel more comfortable and to assist their recovery, especially if antibiotics aren't prescribed. It's important to make a note of these suggestions once kennel cough has been diagnosed. The vet may recommend the use of a humidifier or vaporizer and a safe cough suppressant, for example. He or she may also suggest that the dog avoids smoke-filled environments and stress.
Vets often say that if an infected dog leaves the home he or she should wear a harness instead of a collar. The pressure of the collar on the throat—especially if the dog pulls on the leash—can cause further tissue irritation and increase pain
According to the ASPCA (American Society for the Prevention of Cruelty to Animals), improvement in a dog's condition should be noted about a week after diagnosis. If the dog doesn't get better or gets worse, a second vet visit should be made. The condition can sometimes lead to pneumonia if it doesn't improve.
Precautions to Prevent the Spread of Disease
If an infected dog does leave the home, he or she should have no contact with other dogs. If another dog is seen during a walk, the owner of the sick animal should change their route to avoid meeting the dog. Off-leash areas should be avoided, since other dogs may rush to greet the infected animal. It's important to avoid crowded areas like dog parks as well as areas that many animals visit, such as pet stores and grooming salons.
Despite the recommendations listed above, it's probably not a good idea to take a dog with a bad cough beyond their home and garden except in an emergency. I don't think Misha would have wanted to go for a walk when his cough was bad.
It's important that an infected dog doesn't share his or her toys, food bowls, or drinking bowls with an uninfected animal. In addition, an infected dog mustn't drink out of a dog water bowl in parks or other areas. Contaminated saliva can spread the disease.
The recommended length of the isolation period for a sick dog varies. The most common suggestion is that owners should take steps to prevent the spread of infection for one to two weeks after the symptoms have gone. The bacteria and viruses that cause the disease remain in the body for some time after the symptoms have disappeared.
There is at least one more thing to think about with respect to stopping the spread of the infection. When one dog in a multi-dog family has kennel cough, the other animal or animals in the family may be carrying the causal agent even if they're not sick. My family followed the isolation rules for both Misha and Dylan, the other dog in our home.
Misha received a kennel cough vaccination seven months before his illness developed and wasn't due to get his next shot for another five months, as I realized when I got the receipt for his treatment. The receipts include a health check and vaccination reminder. Obviously the vaccination wasn't effective in Misha's case, or at least not completely effective, assuming Bordetella was at least one cause of his illness.
The Veterinary Health Center at Kansas State University has a webpage about dog vaccinations (referenced below) which gives two possible reasons for the failure of Misha's vaccination. One of the reasons given is that some vaccines—including the Bordetella one—may only minimize a disease instead of preventing it. The page also states that although non-core vaccines are generally given once a year, "the interval may be shorter for some vaccines (i.e. Bordetella) due to increased exposure risk and the possibility of protection not lasting a full year." I'll discuss the situation with my vet when it's time for Misha to receive his core vaccination next year. He's nine at the moment but will be ten when his vaccinations are due. I want to keep him healthy.
The Bordetella vaccine doesn't provide protection from viruses. However, Misha receives an annual DAPP vaccination (Distemper, Adenovirus, Parainfluenza, and Parvovirus), which should protect him from the most common and serious canine viruses. It's possible that his illness was caused primarily by a microbe—or a particular strain of a microbe—not covered by the vaccines that he received, though.
Kennel cough is a very noticeable condition but is usually a relatively minor disorder. It's important to note that it does have the potential to turn into something more serious, especially in some dogs, as shown in the video below.
Kennel Cough Pneumonia in a Puppy
Young puppies, elderly dogs and other immunocompromised animals may take up to six weeks or more to recover.— ASPCA
How Long Does Kennel Cough Last?
The length of a kennel cough infection seems to vary. The ASPCA says that the disease lasts for about three weeks, although there are exceptions, as mentioned in the quote above. The dog may remain infectious for days or even weeks after their symptoms have disappeared.
When I wrote the first edition of this article, Misha hadn’t fully recovered from kennel cough. He was much better than he was at his worst point, though. About four days after we saw the vet, Misha's symptoms started to weaken. His coughs gradually became less frequent and less severe. He has now stopped coughing.
It took fourteen days for Misha's cough to completely disappear, starting from the time of the flare-up in his symptoms. As I say above, though, he may have had a mild version of the illness before the flare-up and before I realized that he needed to see a vet.
Since Misha's recovery from kennel cough is very recent, I'm watching for any signs of the disease in Dylan (who is three years old) and in my three cats. It's hard to imagine that they haven't been exposed to the causal agent, but that doesn't necessarily mean that they'll get sick. Dylan has given a few suspicious coughs, but his condition hasn't progressed any further. Hopefully, everyone will stay healthy.
Information about kennel cough from PetMD
Common dog diseases (including facts about kennel cough) from the ASPCA
Facts about Canine Infectious Respiratory Disease Complex (CIRDC or kennel cough) from the Koret Shelter Medicine Program at the University of California, Davis
Canine adenovirus type-2 and kennel cough facts from Vetstreet
Information about an amoxillan and clavulanic acid combination from the U.S. National Library of Medicine
Facts about dog vaccinations (including the Bordetella vaccination) from the Veterinary Health Center at Kansas State University
© 2017 Linda Crampton