Kennel Cough (Infectious Tracheobronchitis)

Kennel cough (infectious canine tracheobronchitis) is a highly contagious upper respiratory infection caused by a combination of pathogens - most commonly Bordetella bronchiseptica bacteria (often the primary pathogen) alongside various respiratory viruses including parainfluenza, adenovirus type 2, and others. Bordetella can cause disease alone; combined infections tend to be more severe.

The condition is spread through airborne droplets and direct contact - a single infected dog at a training class, a park, or in a boarding facility can spread it to many others rapidly. Despite the name, a dog doesn't need to have been in kennels to contract it.

Classic presentation

• Harsh, dry, honking cough - often described as sounding like the dog has something stuck in its throat. The cough may be triggered by excitement, exercise, or pressure on the trachea (e.g., collar pressure).
• Gagging or retching after coughing - owners often misidentify this as vomiting
• Clear nasal discharge - may progress to purulent (yellow-green) in more complex infections
• Mild lethargy - most dogs remain relatively bright and continue eating normally
• Low or no fever in uncomplicated cases

Most cases are self-limiting. Uncomplicated kennel cough in a healthy adult dog resolves within 1–3 weeks without treatment.

Daily monitoring

For a dog with kennel cough, log daily:

• Cough frequency and character: Getting better, staying the same, or worsening?
• Appetite and water intake: A dog that stops eating warrants vet attention
• Energy level: Generally alert and engaged, or lethargic?
• Temperature if you can take it: Above 39.5°C suggests bacterial complication
• Nasal discharge: Clear or purulent?
• Breathing: Normal? Any increased rate or effort at rest?

The key monitoring question is whether the dog is progressing towards recovery or showing signs of deterioration.

When to worry: pneumonia

In some dogs - particularly puppies, elderly dogs, immunocompromised dogs, or those with concurrent health conditions - kennel cough can progress to pneumonia. Warning signs:

• Worsening cough despite several days passing
• Rapid breathing or respiratory effort at rest
• Lethargy beyond mild tiredness
• Fever
• Loss of appetite for more than 24 hours
• Purulent (yellow-green) nasal or ocular discharge

Pneumonia is a serious complication. If these signs develop, vet assessment the same day is appropriate.

Isolation

Kennel cough is highly contagious. Until the cough has fully resolved:

• Avoid dog parks, training classes, doggy daycare, and contact with other dogs
• Inform your boarding facility or training club if your dog developed kennel cough after attending
• In households with multiple dogs, assume the other dogs have been exposed and monitor them too

Most dogs are contagious for several weeks after clinical signs resolve, though the period of highest contagiousness is during active infection.

Treatment

Uncomplicated kennel cough in a healthy adult dog: supportive management only. Rest, avoiding collar pressure on the trachea (use a harness), and monitoring. Cough suppressants are sometimes prescribed for a particularly productive cough that's disrupting sleep. Antibiotics are not routinely needed for uncomplicated cases.

Complicated kennel cough (progression indicators above, or immunocompromised dog): Antibiotics (doxycycline most commonly) are appropriate. Hospitalisation if pneumonia develops.

Vaccination

The Bordetella vaccine - available as an intranasal spray or oral drops, as well as injectable form - reduces the severity of infection but does not provide complete protection. It is strongly recommended for:

• Dogs that attend kennels (most reputable kennels require up-to-date Bordetella vaccination)
• Dogs regularly at training classes, dog parks, or daycare
• Dogs in multi-dog households

Vaccination is typically annual; some products provide 12-month protection from a single dose. The intranasal or oral route provides faster mucosal immunity (within 72 hours) compared to injectable vaccination (2 weeks to full protection).

When to contact your vet

Contact your vet for a routine appointment or phone advice if:

• The cough has been present for more than a week without any improvement
• You want antibiotic treatment to shorten the course or are unsure of severity

Contact your vet the same day if:

• Rapid breathing or breathing effort at rest
• Refusing food for more than 24 hours
• Significant lethargy beyond mild tiredness
• Fever
• Puppy, elderly dog, or immunocompromised dog

Frequently Asked Questions

My dog has been vaccinated for kennel cough but still got it. Why? The Bordetella vaccine protects primarily against Bordetella bronchiseptica but doesn't protect against all the viral components of kennel cough. It also reduces severity rather than providing complete protection. A vaccinated dog who contracts kennel cough typically has a shorter, milder illness.

How long is my dog contagious? Dogs are typically most contagious during the active infection (while coughing). They continue to shed organisms for some weeks after clinical recovery. Keep affected dogs away from other dogs until the cough has fully resolved, and ideally for a few days beyond that.

My dog coughs occasionally but seems completely normal otherwise - is this kennel cough? Occasional isolated coughing in an otherwise healthy, vaccinated adult dog who hasn't been around other dogs recently may have other causes (heart disease, laryngeal paralysis, collapsing trachea in small breeds, or a foreign body). A persistent cough worth investigating. The classic kennel cough is frequent, harsh, and appears suddenly after exposure.

Can I catch kennel cough from my dog? Bordetella bronchiseptica very rarely causes infection in healthy humans. Immunocompromised individuals have a very small risk. Human infection from dogs is not a practical concern for most households.

Can puppies get kennel cough? Yes, and they are at higher risk of complications including pneumonia. Puppies should be vaccinated from 8 weeks of age. Any coughing illness in a puppy warrants prompt vet assessment.