Much like your catching a “cold”, Kennel Cough is a catch-all term that includes a number of different infections that cause dogs to cough. And just like the common cold, it can be only a small annoyance that lasts a day or two, or something serious enough to keep you home for some time.
The virus and bacteria responsible for kennel cough cause inflammation of your pets wind pipe (trachea) and its branches, the bronchi, that lead to the small passages of the lungs. That is why the medical term for the condition is tracheobronchitis.
The virus and bacteria that cause kennel cough are spread through the air. They are very infectious when a susceptible dog inhales them. The dog that infected your pet may not have had a cough problem himself. Not all dogs that become infected develop a cough. But their nasal and respiratory secretions are still infectious to other dogs.
Dogs that stay at home, apart from newly arrived pets, do not develop kennel cough. The organisms that cause the disease are very rarely carried to your pet on contaminated objects. To catch kennel cough, your dog almost certainly was exposed directly to another infected pet.
Not every exposure to a sick dog will cause kennel cough in a dog. But there are some common stressors and situations that will make it more likely to develop a cough :
1) Exposing your pet to other dogs is the most important cause of kennel cough. This occurs most frequently at groomers, pet shows, kennels, doggy parks animal shelters, vaccination clinics and veterinary hospitals. It does not require that a coughing dog be present - recovered dogs can shed the organisms for 3-4 months.
2) Shipping is quite stressful to pets. It can lower their resistance to many infections. However shipping in-itself does not cause kennel cough unless a sick or recovering animal is included in the shipment. It does cause some animals to develop a cough who would not have, had they not been stressed by shipping. Remember – most pets exposed the these viruses and bacteria overcome them without developing a cough.
3) Crowding and poor air circulation also increase the likelihood that your pet will inhale a respiratory virus or bacteria.
4) Dust, cigarette smoke and cold temperature are all unpleasant to your pet. But they will not cause kennel cough and more than they will cause you to develop a common cold. The respiratory system of your pet is lined with a protective layer of cells with fine hairs called cilia and covered in a thin layer of protective mucous. These hairs act as an escalator, continuously move inhaled dust, debris and bacteria out through your pets mouth and nose. Perhaps unhealthy conditions decrease the effectiveness of this system against the organisms of kennel cough, making an infection more likely when your pet is exposed to respiratory tract disease.
Pets are often exposed to several different respiratory disease
organisms at the same time. So your pet’s case of kennel cough
may be due to the combined effects of two or more “bugs”
attacking its respiratory system at the same time.
The organism most frequently associated with kennel cough in the United States is a bacteria called Bordetella bronchiseptica. It infects cats, ferrets, guinea pigs and rabbits as well as dogs - but it only rarely affects humans. Some strains of the bacteria are more potent than others. Most common disinfectants kill bordatella, but it remains infective in a damp environment. Recovered dogs can shed the Bordetella organism for several months after they have recovered.
Other bacteria, such as Streptococcus, Pseudomonas, E. coli , and Klebsiella have also been isolated from dogs with an infectious cough.
Several virus are also involved in kennel cough.
One of the most important ones is the canine parainfluenza virus (CPIV). When this virus enters a dog’s body alone, it causes a very mild disease or none at all. However, when it enters with a group of other invaders, it seems to make kennel cough signs more likely and more intense. Most kennel cough vaccines contain the weakened parainfluenza virus. But they only lessen the severity of the symptoms your dog might develop - they usually do not block infection. (ref)
Another virus that is often isolated from dogs with kennel cough is the canine adenovirus-2 (CAV-2). Many dogs will develop a cough within a week of being exposed to this virus. In some dogs, CAV-2 virus also causes conjunctivitis, sneezing and a nasal discharge.
Canine reoviruses 1, 2 & 3, canine adenovirus–1 , canine herpesvirus, canine respiratory coronavirus (CRCoV) and mycoplasma have all been isolated from coughing dogs. But it is unclear how important a part they play in the disease.
Canine Distemper is a very serious disease of dogs. One of the early signs of canine distemper is a soft, dry cough. Many cases of distemper are complicated by the same organisms that are involved in kennel cough. However, distemper virus is not a part of the condition we refer to as kennel cough.
Kennel cough is a highly infectious disease. Some other diseases spread only when disease organisms are swallowed. Others require intermediate hosts - like ticks. But the organisms that cause kennel cough move primarily through the air. A sick or recovering dog in the presence of other unexposed and unvaccinated, dogs is almost a guarantee that the unexposed dogs will also become infected.
What Would My Dog Sound Like If It Had It ?
A persistent hacking cough is the most common sign of kennel cough. Often the coughing spell ends with a gagging or retching sound and the production of some foam. Exertion and excitement often make the cough worse. Kennel cough tends to be worse and linger longer in narrow-trachea toy breeds like pomeranians, toy poodles and miniature dachshunds.
Dogs generally develop a cough 2-14 days after being exposed.
Most pets experience only a cough and perhaps mild listlessness. But some run fevers and loose their appetite due to tonsillitis. A few unfortunate pets develop secondary problems such as pneumonia. These are generally dogs whose immune systems are weakened by stress, parasites,old age, poor nutrition, or other concurrent medical problems.
Uncomplicated kennel cough is not a serious disease. It becomes serious if bacteria begin to grow in the lungs themselves, causing pneumonia, or when it makes conditions such as a narrow, inflamed windpipe worse. It can be more serious in very young and very old dogs. Again, dogs weakened by chronic stress, parasites, inadequate diet or pre-existing health problems are the ones most likely to need medical care and to take longer to recover. When it does lead to pneumonia in compromised pets, the pneumonia can be life-threatening.
The presence of a typical cough in a pet that was recently exposed to another strange dog will lead your veterinarian to suspect kennel cough. Veterinarians generally make the diagnosis by ruling out other more serious problems that might cause a persistent cough. These are things like heart problems, heartworms, tracheal abnormalities, and certain lung conditions. If your pet does not appear ill on its physical examination, other tests are usually not required. If your veterinarian becomes suspicious that this may be more than a common case of kennel cough, he/she might suggest a chest x-ray and some lab work.
The vast majority of cases of kennel cough resolve without veterinary treatment. TLC, warmth, low stress and a balanced diet all speed recovery.
Most veterinarians will treat your pet conservatively with a cough suppressant and, perhaps, some antibiotics and reserve further testing and treatment options for the few animals that do not fully recover in a week or two.
Veterinarians hesitate to hospitalize dogs with uncomplicated kennel cough. First, they usually recover faster at home and second, they tend to spread their infection to the other hospitalized patients.
If your dog is in distress and your veterinarian has ruled out anything more serious than kennel cough, the pet may feel better with aerosolized (nebulized) compounds that dilate the lungs (ipratropium, Atrovent, aminophylline,albuterol) or that loosen and break up mucus. (Mucomyst). Many pets feel better after steam treatments to relieve congestion.
When coughs persist too long , antibiotics combined with corticosteroids and narcotic cough suppressants are sometimes needed.
Just like the colds you get, kennel cough in your pet will almost always get better on its own with time. In uncomplicated cases, where your pet's energy level is not affected, antibiotics will not make your dog stop coughing any sooner. What unnecessary antibiotics might do, is produce a group of antibiotic-resistant bacteria in your household. Bacteria normally transfer from your pet to you and from you to your pet. When your family members, you or your pet(s) later need to fight life-threatening illnesses, these antibiotics may no longer work. This problem is called antibiotic resistance. Because It is tough for us veterinarians to send concerned pet owners home without a bottle of something to give their pet, please do not encourage us to give more than a temporary cough suppressant if that is all that is required.
However, there are pets that definitely do need antibiotics. Those are often the toy breeds that have narrow or collapsed tracheas (windpipes) (ref), dogs with heart problems or those debilitated by other chronic disease or old age. In those pets, common kennel cough can progress to serious pneumonia or produce a cough that lingers on for weeks. Any dog that coughs frequently for more than a week is a candidate for antibiotics - and probably needs a health examination to explain why the cough has lasted so long. A 7-10 day course of doxycycline is often your vet's first choice. Doxy, should be given to dogs with food (and always followed by a syringe of soup or water in cats). If it still causes vomiting, nausea, poor appetite or diarrhea, then azithromycin is probably the next best choice. Read about your vet's antibiotic choices here .
Can My Cat or I Catch it ?
Your cat and pocket pets are susceptible to Bordetella and the other bacteria sometimes isolated from kennel cough. They and you are not susceptible to the viruses implicated in canine kennel cough. There have only been a few recorded cases of Bordetella infecting humans. These were generally people with other chronic health problems.
Most dogs stop coughing in one to two weeks. However, some pets develop a cough that lingers much longer. Once your veterinarian has eliminated the possibility of another, more serious disease, you will need patience waiting for your pet to stop coughing. I do become concerned when coughs become worse rather than better. As long as there is a slow, steady decrease in the frequency of the cough, things are on the mend.
Yes, none of the organisms implicated in kennel cough give lasting immunity.
The best prevention is to expose your pet to other non-family dogs as little as possible.
Veterinarians vaccinate for some of the organisms that cause kennel cough. Most vaccines of this type contain the CAV-2 virus and Bordetella. These vaccines are not fool proof. Vaccination against CAV-2 will not prevent infection with this virus but will lessen the severity of the disease if the dog is later exposed.
Many boarding kennels require a current kennel cough vaccination for all boarders. If more than 6 months have passed since your pet’s last kennel cough vaccination, a booster vaccination is a good idea. I like to give the vaccine at least 5 days before boarding – although protection develops with some brands of vaccine as early as 72 hours following vaccination.
Kennel Cough vaccines exist in two forms: One that is given by injection and one that is given as drops placed in your pet's nose (Intra-Trac 3, Bronchi-Shield III ). The injectable vaccine is of little or no value. If the intra-nasal vaccine is accidentally give to your pet by injection, the result can be a very severe reaction. Some vets still use the injectable product because frees them from this concern.
It is thought that the intra-nasal form of the vaccine stimulated local defense immunity in the areas that the virus is most likely to enter first. This is something injectable kennel cough vaccines cannot do. Puppies can receive this vaccine as early as three weeks of age and some degree of immunity seems to persist for up to a year. A few dogs will develop short-term sneezing and nasal discharge following the intra-nasal vaccination.
Breeders and show handlers still sometimes give their dogs both the injectable and the intra-nasal vaccine because kennel cough is such a problem on the show circuits.
Vaccines given to protect against canine distemper usually also contain and protect against the parainfluenza and adenovirus type 2 organisms involved in kennel cough. They do not contain or protect against Bordetella.