Bordetella and Infectious Tracheobronchitis in Dogs
Infectious tracheobronchitis is the inflammation of the upper respiratory tract in dogs caused by infectious pathogens. This is commonly known as “kennel cough,” and can occur secondary to multiple viruses and the bacteria Bordetella bronchiseptica. Other bacteria can also act as secondary pathogens, but aren’t the primary inciting cause.
The viruses most commonly associated with infectious tracheobronchitis include canine parainfluenza, canine adenovirus 2 (CAV-2), and canine distemper virus. Other viruses that may play a part in this disease process, but haven’t directly been linked, include: canine reovirus (1, 2 and 3), canine adenovirus 1 (CAV-1), and canine herpesvirus. Bordetella bronchiseptica is the primary bacterial pathogen associated with this disease process but Pseudomonas sp, Escherichia coli and Klebsiella pneumoniae may contribute as secondary pathogens.
What Dogs Are at Risk for Bordetella?
The disease is associated most often with dogs housed in a high-density population or boarding kennels. If your dog is frequently boarded, goes to the groomer, dog park, or doggy day care, or interacts with other dogs, vaccination is recommended. Puppies and younger dogs are at greatest risk due to their naive immune system, but old dogs can even acquire kennel cough. Most facilities that participate in boarding, day care, and grooming require dogs to be vaccinated against Bordetella.
How Is Bordetella Transmitted in Dogs?
The infectious agents can be transmitted through the air with respiratory secretions, direct contact with infected dogs, or through exposure on surfaces.
What Are Signs of a Bordetella Infection?
The cough associated with acute infectious tracheobronchitis (ITB) is a dry, high-pitched, honk-like cough, often followed by retching. It is often worse during periods of physical activity and can persist for minutes on end. Other signs may include irritated eyes, rhinitis (runny nose), or sneezing. More severe signs include loss of appetite, depression, or fever.
Puppies under 6 months of age tend to be more severely affected by infectious tracheobronchitis and can have more severe clinical signs. Most adult dogs will have mild signs that are self limiting and recover without complications.
The incubation period from the time the dog first contracts the infection to the time that symptoms develop is typically between 3 to 10 days, and the symptoms can last for days to weeks. A mild to moderate cough without other symptoms is usually self-limiting, however, causes can linger and lead to chronic bronchitis.
Any of these signs should prompt a visit to your veterinarian in order to ensure that infection hasn’t spread to lungs and developed into pneumonia.
How Is Infectious Tracheobronchitis Diagnosed?
Most cases of kennel cough are diagnosed by a physical exam, history of possible exposure, and clinical signs. There are PCR respiratory panels that can be submitted that will screen for known viral causes, in addition to Bordetella bronchiseptica. This panel is useful to look for other underlying viral causes that can mimic kennel cough. If pneumonia is a concern or suspected, radiographs will be recommended.
What Are Treatment Measures for Infectious Tracheobronchitis?
Most dogs will recover with mild signs and no treatment. Antibiotics are prescribed to certain dogs to shorten the course of disease and to prevent secondary infections. In young puppies, geriatric dogs, or dogs with other underlying health conditions, the infection can be more severe and require hospitalization with IV fluids, antibiotics, and oxygen supplementation.
When Is the Bordetella Vaccine Recommended?
The vaccine to protect against Bordetella in dogs is recommended for dogs at risk of exposure. The highest risk dogs are housed in a high-density population or boarding kennel.
How Is the Bordetella Vaccine Administered?
The bordetella vaccine can be given intranasal or by injection. The intranasal vaccine may make patients immune faster, but either method is acceptable.
The American Animal Hospital Association provides the following vaccination recommendations:
- Puppies can be vaccinated using the intranasal vaccine as early as 3 weeks of age (depending on the product label). A second dose should be given two to four weeks later. This is recommended for puppies with high risk of exposure.
- Puppies can receive the injectable vaccine starting at 6 to 8 weeks of age, followed by a booster three to four weeks later between the ages of 10 and 12 weeks.
- For adult dogs or puppies over 16 weeks of age, the intranasal vaccine can be given once OR the injectable vaccine can be given twice, two to four weeks apart.
- Dogs should receive boosters every 12 months, depending on exposure risk.
For all vaccines, it is important to vaccinate at least 5 days before potential exposure. Vaccines do not work immediately. It takes time for the body to respond to the vaccine, develop immunity, and provide protection against the specific disease.
What Is the Difference Between Infectious Tracheobronchitis and Canine Influenza?
Canine influenza or Canine flu can closely mimic infectious tracheobronchitis, but they aren’t the same disease process. Canine influenza (CI) is an infectious virus that can spread quickly through naive populations of dogs. The two canine influenza viruses that are present right now are H3NB and H3N2. These are different from the H3N2 strain that affects people yearly. Dog’s can not get human flu strains and humans can not get canine influenza.
Canine influenza outbreaks can happen in highly-populated boarding facilities, daycares, and groomers, similar to kennel cough infections. Transmission of the viruses are similar, since flu is also transmitted through airway secretions and exposure in the environment. Clinical signs are similar to canine tracheobronchitis, but tend to be more severe.
- Retching after coughing
- Profound lethargy
- Nasal discharge
- Excessive drooling
Canine influenza infections can be more severe than normal kennel cough infections. Unfortunately, some dogs with canine flu can develop severe pneumonia, which requires hospitalization and oxygen support. Canine influenza can be fatal if severe forms develop, with a noted fatality rate of <10%.
There is a vaccine available for canine influenza that covers both strains of the virus. This vaccine is recommended for dogs with risk of exposure.
Please have your dog evaluated by a veterinarian at any point if concerned about infectious tracheobronchitis or canine influenza.