| Infectious Tracheobronchitis: 'Kennel Cough' Veterinary & Aquatic Services Department, Drs. Foster & Smith, Inc. |
'Kennel Cough' is the term that was commonly applied to the most prevalent upper respiratory problem in dogs
in the United States. Recently, the condition has become known as tracheobronchitis, canine infectious
tracheobronchitis, Bordetellosis, or Bordetella. It is highly contagious in dogs. The disease is found worldwide
and will infect a very high percentage of dogs in their lifetime.
Infectious agents involved
There are many different agents that contribute to the disease process of tracheobronchitis. The most
common are parainfluenza, Bordetella bronchiseptica, and mycoplasma. Canine adenovirus, reovirus, and canine
herpes virus are thought to possibly contribute to the disease. Although any one of these organisms can cause
symptoms of the disease, the majority of cases are the result of more than one organism.
The most common viral agent is parainfluenza virus. This common virus will cause mild symptoms lasting less
than 6 days unless there is involvement with other bacteria, as is usually the case. Most 5-way vaccines and
'kennel cough' vaccines offer some protection against this virus.
Bordetella bronchiseptica is the most common bacteria isolated from this disease. Clinical signs of infections
occur three to four days after exposure, and if uncomplicated with other agents, will last around 10 days.
However, after the infection has been resolved, the affected animal will continue to shed the bacteria for 6
to 14 weeks and can spread the disease to other susceptible animals during that time. Bordetella is one of the
agents protected against through the use of intranasal 'kennel cough' vaccines. Parainfluenza and Bordetella
most commonly appear together in infectious tracheobronchitis, creating a disease that normally lasts from
14-20 days.
Symptoms
The most common symptom is a dry hacking cough sometimes followed by retching. Many owners describe the
cough as having a 'honking sound.' A watery nasal discharge may also be present. With mild cases, dogs continue
to eat and be alert and active. Many times, there is a recent history of boarding or coming in contact with
other dogs. In more severe cases, the symptoms may progress and include lethargy, fever, inappetence,
pneumonia, and in very severe cases, even death. The majority of severe cases occur in immunocompromised
animals, or young unvaccinated puppies.
Diagnosis
Diagnosis is usually based on the symptoms and a history of recent exposure to other dogs. Bacterial cultures,
viral isolation, and blood work can be performed to verify individual agents of the disease, but due to the
characteristic nature of the symptoms are not routinely performed.
Treatment
There are two treatment options depending on the severity of the disease. In the most common mild
(uncomplicated) form of the disease, antibiotics are usually not used. If the dog has a good appetite and is
alert but suffers only from a recurrent cough, we will often let the disease run its course just as we would
with a cold in humans. Treating the mild case does not shorten the length in which the animal will be a potential
spreader of the disease. Many times, prednisone is given to help reduce the severity and frequency of the
cough and to make the dog more comfortable. In addition, Bronchodilators like aminophylline or cough
suppressants may also be used.
In more severe (complicated) cases where the animal is not eating, running a fever, or showing signs of
pneumonia, antibiotics are often used. The most common ones are tetracycline or trimethoprim-sulfa.
However, many other choices are also available. Steroids or cough suppressants are not usually recommended
because of the risk of immunosuppressive with steroids and the need to continue to clear extra fluid or
mucous in pneumonia patients. Bronchodilators and even aerosol therapy can be used. In moderate or severe
cases, veterinary care should be instituted, as the resultant pneumonia could become life threatening if not
treated properly and promptly.
Vaccination and prevention
The best prevention is to not expose your dog to other dogs, especially young puppies. If this cannot be
avoided, then proper vaccination is the next best option. Chances are that if your dog is regularly vaccinated
with a standard 5-way or 7-way vaccine, he is already being protected against several of the agents causing
tracheobronchitis, mainly parainfluenza and adenovirus. However, these vaccines alone rarely provide
protection against contracting the disease, although they will help reduce the severity of the disease if the
animal becomes infected.
More commonly, for best protection, an intranasal vaccine containing both parainfluenza and Bordetella is used.
Intranasal vaccines create localized immunity that greatly reduces the incidence of clinical signs and illness.
There are several precautions and warnings that need to be observed pertaining to this vaccine. Some dogs
will develop mild signs similar to tracheobronchitis when given this vaccine. Very often, the symptoms will last
for several days and the dog will recover without treatment. Dogs that are vaccinated can also shed the virus
and cause other dogs to become mildly infected and show mild signs. This shedding usually lasts less than 72
hours. In addition, it takes up to 4 days after vaccination for dogs to develop protection. When you combine
these facts, you will see why I strongly recommend that a dog not be given intranasal vaccine within 72 hours
of coming into contact with other susceptible dogs. Do not give the vaccine the day before a dog show,
boarding, etc. Try to give at least four days before contact with other dogs, and preferably 7 days. This way
you will protect your dog from becoming infected by other dogs, and protect those dogs from becoming
infected by yours.
This vaccine is not without its problems. It is a very effective vaccine, but it must be used carefully and is
generally only recommended for dogs that are at high risk. If your dog is not shown, boarded, or comes into
contact with stray dogs, your dog is considered low risk.
In kennels where tracheobronchitis is a problem, strict hygiene with thorough cleaning and disinfection of
cages and food and water containers is essential. In addition, kennels that are indoors should have good
ventilation with an air turnover rate of at least 12 times an hour. Agents causing tracheobronchitis can be
transmitted on hands and clothing as well as through the air, so infected animals must be isolated and handlers
should wear gloves and use proper handwashing to help prevent spread. Vaccination of all animals, especially
puppies is indicated in problem kennels. After initial vaccination as puppies, a yearly booster is recommended.
However, some dogs that are at very high risk are vaccinated every six months.
Human health risk
Until recently, infectious tracheobronchitis was considered to not be a human health risk. Recently however,
research indicates that Bordetella bronchiseptica may cause disease in some humans, primarily those with
compromised immune systems. In normal, healthy adults there does not appear to be a risk factor, but young
children and immunocompromised individuals should take precautions against coming into contact with animals
that have symptoms of tracheobronchitis.
Summary
'Kennel Cough,' now more commonly referred to as 'infectious tracheobronchitis' is a widespread disease
caused by several different viruses and bacteria. It is usually a self-limiting disease and most animals do not
require treatment. Intranasal vaccines are effective, but due to some possible side effects, are
recommended for animals that are at higher risk. Infectious tracheobronchitis is a disease of dogs and wild
canids, it does not appear to be a risk to healthy humans or cats.
References
Ettinger, S. Textbook of Veterinary Internal Medicine. W,B. Saunders Co. Philadelphia, PA; 1989.
Foster, R.; Smith, M. What's the Diagnosis. Macmillan. New York, NY; 1996.
Greene, C. Infectious Diseases of the Dog and Cat. W.b. Saunders Co. Philadelphia, PA; 1998.
Copyright © 1997-2004, Drs. Foster & Smith, Inc. All Rights Reserved.
Reprinted from PetEducation.com.
in the United States. Recently, the condition has become known as tracheobronchitis, canine infectious
tracheobronchitis, Bordetellosis, or Bordetella. It is highly contagious in dogs. The disease is found worldwide
and will infect a very high percentage of dogs in their lifetime.
Infectious agents involved
There are many different agents that contribute to the disease process of tracheobronchitis. The most
common are parainfluenza, Bordetella bronchiseptica, and mycoplasma. Canine adenovirus, reovirus, and canine
herpes virus are thought to possibly contribute to the disease. Although any one of these organisms can cause
symptoms of the disease, the majority of cases are the result of more than one organism.
The most common viral agent is parainfluenza virus. This common virus will cause mild symptoms lasting less
than 6 days unless there is involvement with other bacteria, as is usually the case. Most 5-way vaccines and
'kennel cough' vaccines offer some protection against this virus.
Bordetella bronchiseptica is the most common bacteria isolated from this disease. Clinical signs of infections
occur three to four days after exposure, and if uncomplicated with other agents, will last around 10 days.
However, after the infection has been resolved, the affected animal will continue to shed the bacteria for 6
to 14 weeks and can spread the disease to other susceptible animals during that time. Bordetella is one of the
agents protected against through the use of intranasal 'kennel cough' vaccines. Parainfluenza and Bordetella
most commonly appear together in infectious tracheobronchitis, creating a disease that normally lasts from
14-20 days.
Symptoms
The most common symptom is a dry hacking cough sometimes followed by retching. Many owners describe the
cough as having a 'honking sound.' A watery nasal discharge may also be present. With mild cases, dogs continue
to eat and be alert and active. Many times, there is a recent history of boarding or coming in contact with
other dogs. In more severe cases, the symptoms may progress and include lethargy, fever, inappetence,
pneumonia, and in very severe cases, even death. The majority of severe cases occur in immunocompromised
animals, or young unvaccinated puppies.
Diagnosis
Diagnosis is usually based on the symptoms and a history of recent exposure to other dogs. Bacterial cultures,
viral isolation, and blood work can be performed to verify individual agents of the disease, but due to the
characteristic nature of the symptoms are not routinely performed.
Treatment
There are two treatment options depending on the severity of the disease. In the most common mild
(uncomplicated) form of the disease, antibiotics are usually not used. If the dog has a good appetite and is
alert but suffers only from a recurrent cough, we will often let the disease run its course just as we would
with a cold in humans. Treating the mild case does not shorten the length in which the animal will be a potential
spreader of the disease. Many times, prednisone is given to help reduce the severity and frequency of the
cough and to make the dog more comfortable. In addition, Bronchodilators like aminophylline or cough
suppressants may also be used.
In more severe (complicated) cases where the animal is not eating, running a fever, or showing signs of
pneumonia, antibiotics are often used. The most common ones are tetracycline or trimethoprim-sulfa.
However, many other choices are also available. Steroids or cough suppressants are not usually recommended
because of the risk of immunosuppressive with steroids and the need to continue to clear extra fluid or
mucous in pneumonia patients. Bronchodilators and even aerosol therapy can be used. In moderate or severe
cases, veterinary care should be instituted, as the resultant pneumonia could become life threatening if not
treated properly and promptly.
Vaccination and prevention
The best prevention is to not expose your dog to other dogs, especially young puppies. If this cannot be
avoided, then proper vaccination is the next best option. Chances are that if your dog is regularly vaccinated
with a standard 5-way or 7-way vaccine, he is already being protected against several of the agents causing
tracheobronchitis, mainly parainfluenza and adenovirus. However, these vaccines alone rarely provide
protection against contracting the disease, although they will help reduce the severity of the disease if the
animal becomes infected.
More commonly, for best protection, an intranasal vaccine containing both parainfluenza and Bordetella is used.
Intranasal vaccines create localized immunity that greatly reduces the incidence of clinical signs and illness.
There are several precautions and warnings that need to be observed pertaining to this vaccine. Some dogs
will develop mild signs similar to tracheobronchitis when given this vaccine. Very often, the symptoms will last
for several days and the dog will recover without treatment. Dogs that are vaccinated can also shed the virus
and cause other dogs to become mildly infected and show mild signs. This shedding usually lasts less than 72
hours. In addition, it takes up to 4 days after vaccination for dogs to develop protection. When you combine
these facts, you will see why I strongly recommend that a dog not be given intranasal vaccine within 72 hours
of coming into contact with other susceptible dogs. Do not give the vaccine the day before a dog show,
boarding, etc. Try to give at least four days before contact with other dogs, and preferably 7 days. This way
you will protect your dog from becoming infected by other dogs, and protect those dogs from becoming
infected by yours.
This vaccine is not without its problems. It is a very effective vaccine, but it must be used carefully and is
generally only recommended for dogs that are at high risk. If your dog is not shown, boarded, or comes into
contact with stray dogs, your dog is considered low risk.
In kennels where tracheobronchitis is a problem, strict hygiene with thorough cleaning and disinfection of
cages and food and water containers is essential. In addition, kennels that are indoors should have good
ventilation with an air turnover rate of at least 12 times an hour. Agents causing tracheobronchitis can be
transmitted on hands and clothing as well as through the air, so infected animals must be isolated and handlers
should wear gloves and use proper handwashing to help prevent spread. Vaccination of all animals, especially
puppies is indicated in problem kennels. After initial vaccination as puppies, a yearly booster is recommended.
However, some dogs that are at very high risk are vaccinated every six months.
Human health risk
Until recently, infectious tracheobronchitis was considered to not be a human health risk. Recently however,
research indicates that Bordetella bronchiseptica may cause disease in some humans, primarily those with
compromised immune systems. In normal, healthy adults there does not appear to be a risk factor, but young
children and immunocompromised individuals should take precautions against coming into contact with animals
that have symptoms of tracheobronchitis.
Summary
'Kennel Cough,' now more commonly referred to as 'infectious tracheobronchitis' is a widespread disease
caused by several different viruses and bacteria. It is usually a self-limiting disease and most animals do not
require treatment. Intranasal vaccines are effective, but due to some possible side effects, are
recommended for animals that are at higher risk. Infectious tracheobronchitis is a disease of dogs and wild
canids, it does not appear to be a risk to healthy humans or cats.
References
Ettinger, S. Textbook of Veterinary Internal Medicine. W,B. Saunders Co. Philadelphia, PA; 1989.
Foster, R.; Smith, M. What's the Diagnosis. Macmillan. New York, NY; 1996.
Greene, C. Infectious Diseases of the Dog and Cat. W.b. Saunders Co. Philadelphia, PA; 1998.
Copyright © 1997-2004, Drs. Foster & Smith, Inc. All Rights Reserved.
Reprinted from PetEducation.com.
| This site was created by and is maintained by Belinda Winters for BFH Bassets. If you have any questions or comments email belindawinters@bfhbassets.com |
| This site was created by and is maintained by Belinda Winters for BFH Bassets. If you have any questions or comments email belindawinters@bfhbassets.com |
