What Is Kennel Cough?
Kennel cough — known medically as infectious tracheobronchitis — is a highly contagious respiratory infection affecting dogs of all ages and breeds. Despite its name, dogs do not need to have visited a kennel to contract it. The condition can be picked up anywhere that dogs meet: at the park, training classes, grooming salons, or even on a brief pavement encounter with an infected animal.
The illness is characterised by inflammation of the trachea (windpipe) and bronchi, producing the distinctive cough that gives the condition its name. It is almost always distressing for owners to witness but is rarely dangerous in otherwise healthy adult dogs. Puppies, elderly dogs, and immunocompromised animals are at greater risk of developing complications.
Causative Agents
Kennel cough is not caused by a single pathogen but rather by a combination of infectious agents that act together to overwhelm the respiratory defences. The most important include:
Bordetella bronchiseptica
The bacterium Bordetella bronchiseptica is considered the primary bacterial cause of kennel cough. It attaches to the cilia — the tiny hair-like structures lining the respiratory tract that normally sweep debris and pathogens away — and prevents them from functioning effectively. This creates the opportunity for secondary infection and prolongs recovery. Bordetella is the agent targeted by the most commonly used kennel cough vaccines.
Canine Parainfluenza Virus
Canine parainfluenza virus is a frequent co-infector that causes its own mild respiratory illness but significantly worsens disease severity when combined with Bordetella. It spreads rapidly through aerosol droplets and can survive briefly on contaminated surfaces, making transmission in busy environments very efficient.
Canine Adenovirus Type 2
Canine adenovirus type 2 (CAV-2) is another viral contributor to the kennel cough complex. Unlike adenovirus type 1, which causes infectious canine hepatitis, CAV-2 primarily targets the respiratory tract. Many combination vaccines include protection against CAV-2 as part of routine preventative care.
Other pathogens — including canine respiratory coronavirus, canine herpesvirus, and Mycoplasma species — can also contribute to the kennel cough syndrome, which is why the illness can persist even in vaccinated dogs.
Recognising the Symptoms
The hallmark of kennel cough is a harsh, forceful cough that is often described as sounding like a goose honking. This distinctive noise is produced by the inflamed trachea and is quite different from the softer cough associated with heart disease or the occasional cough of a dog that has swallowed water too quickly.
The cough may be triggered by excitement, exercise, or gentle pressure on the throat. Many dogs will retch or gag at the end of a coughing bout, sometimes producing a small amount of white foam. Despite the dramatic sound of the cough, most affected dogs remain bright, alert, and interested in food.
Other signs can include a mild nasal discharge, sneezing, and slight lethargy. A high temperature, loss of appetite, lethargy, or green/yellow nasal discharge suggest the infection has become more serious and warrants prompt veterinary attention, as these may indicate secondary bacterial pneumonia.
Is Kennel Cough Self-Limiting?
In the majority of cases, yes. Kennel cough in healthy adult dogs typically runs its course within two to three weeks without any specific treatment. The immune system clears the infection, the respiratory inflammation settles, and the dog returns to normal. Owners can help their dog recover comfortably by ensuring it rests, stays well hydrated, and is not subjected to strenuous exercise during the illness.
Swapping a standard collar for a harness during recovery is advisable, as pressure on the throat from a collar can trigger coughing bouts and cause additional irritation to an already inflamed trachea.
When Are Antibiotics Needed?
Because kennel cough frequently has a significant viral component, antibiotics will not resolve the infection entirely. However, they are indicated in certain situations. Dogs that are systemically unwell — showing high temperature, loss of appetite, significant lethargy, or signs of pneumonia — should be seen by a vet promptly, and a course of antibiotics targeting Bordetella and other bacterial pathogens is likely to be prescribed.
Puppies, elderly dogs, and dogs receiving immunosuppressive medication are also candidates for antibiotic treatment even if they do not initially appear severely ill, as these groups are at higher risk of deterioration. Your vet may also prescribe cough suppressants to provide comfort in dogs where the coughing is particularly severe or persistent.
Isolation Advice
To prevent spreading kennel cough to other dogs, a two-week isolation period is recommended from the onset of signs. This means avoiding dog parks, group walks, grooming appointments, training classes, and kennels. Even after clinical signs have resolved, a dog may continue to shed infectious agents for a short period, so completing the full isolation period is important rather than ending it as soon as the cough improves.
Inform any dog owners whose animals have recently been in contact with your dog, so that they can monitor for signs and keep their pets away from other dogs as a precaution.
Vaccination: What It Can and Cannot Do
Vaccination against kennel cough is widely available and is required by most reputable kennels before dogs are admitted. The most common form is an intranasal vaccine containing live attenuated Bordetella bronchiseptica and parainfluenza virus, which is administered directly into the nostril. Injectable and oral options are also available.
Vaccination reduces the severity of illness if a dog is exposed and may reduce the duration of infection, but it does not provide complete protection against all strains and all causative agents. Vaccinated dogs can still contract kennel cough — particularly from agents not covered by the vaccine — but they are less likely to become seriously ill.
Immunity following vaccination is not lifelong. Annual boosters are recommended to maintain reasonable protection, and some kennels require vaccination within six months of the dog's stay. If your dog has never been vaccinated against kennel cough, speak to your vet about adding it to their routine health care plan.
Reducing the Risk
Beyond vaccination, sensible management can help reduce your dog's exposure to kennel cough. Avoid busy dog areas during local outbreaks, ensure your dog's core vaccinations are up to date, and choose boarding kennels or doggy daycare providers that require all dogs to be vaccinated before entry. A good diet, regular exercise, and appropriate parasite control all contribute to a robust immune system better able to resist infection.
Kennel cough is rarely serious in healthy, vaccinated dogs, but it is unpleasant and highly contagious. Taking a few straightforward precautions significantly reduces the likelihood of your dog catching it — and the risk of passing it on to others.