The dry, honking cough that appears three days after a boarding kennel, a dog show or a busy park is one of the most recognisable things in dog ownership. Most cases are miserable, noisy, and entirely self-limiting.
Some are not, and the difference is worth knowing.
What it actually is
“Kennel cough” is a lay term for canine infectious respiratory disease complex — which is a mouthful, but the word *complex* is the informative bit. It is not one organism. It is a set of viruses and bacteria that inflame the upper airway, often in combination.
The usual suspects:
- Bordetella bronchiseptica — the bacterium most people associate with it
- Canine parainfluenza virus
- Canine adenovirus type 2
- Canine respiratory coronavirus — unrelated to the human virus
- Mycoplasma species
- Canine influenza, in some regions
Most clinical cases involve more than one of these, which matters because it explains why a vaccinated dog can still catch something.
How it spreads
Through the air, over short distances, and on shared surfaces. Anywhere dogs congregate:
- Boarding kennels and daycare
- Grooming salons
- Training classes and shows
- Busy parks, and shared water bowls
- Veterinary waiting rooms
Incubation is typically two to ten days. A dog can be infectious before they cough and for one to three weeks afterwards — longer with some organisms.
The signs
The classic: a sudden, dry, forceful, honking cough, often described by owners as the dog having something stuck in their throat. It frequently ends with a retch or a gag that brings up white foam, which people mistake for vomiting.
The cough is typically worse with excitement, exercise, pressure on the throat from a collar, and at night.
Otherwise, a dog with straightforward kennel cough is bright, eating, and behaving normally. That is the key feature.
When to ring the vet
Straightforward cases often do not need treatment, but ring if:
- Your dog is lethargic, off their food, or feverish
- There is nasal or eye discharge, particularly if thick or coloured
- Rapid or laboured breathing, or breathing effort at rest
- The cough is productive — bringing up material rather than foam
- Your dog is a puppy, a senior, pregnant, or immunocompromised
- Your dog is brachycephalic — Pugs, French Bulldogs, Bulldogs already have compromised airways and tolerate respiratory infection poorly
- There is any heart disease in the history
- The cough persists beyond three weeks
- Symptoms are getting worse rather than better after the first few days
A small proportion of cases progress to pneumonia, and that is the thing the list above is designed to catch.
Phone ahead. Do not walk a coughing dog into a full waiting room. Most practices will ask you to wait in the car.
Treatment
For an otherwise well dog, usually supportive care:
- Rest. Restrict exercise for the duration. The cough is aggravated by exertion, and a dog who runs around coughs more and heals slower
- Harness instead of collar. Anything pressing on the trachea sets off a coughing fit
- Humidity. Sitting in a steamy bathroom for ten minutes helps some dogs
- Soft food if swallowing is uncomfortable
- Water always available
Antibiotics are not automatic. Most cases are viral or self-limiting, and reflexive antibiotic use drives resistance. Vets prescribe them when there is evidence of bacterial involvement — fever, coloured discharge, abnormal lung sounds, or a case that is not improving.
Cough suppressants are sometimes prescribed for a dog whose cough is preventing sleep, but they are not used where there is any suspicion of pneumonia, because suppressing a productive cough traps material in the lungs.
Do not give human cough medicine. Many contain paracetamol, decongestants or xylitol.
How long it lasts
Most dogs improve substantially within seven to ten days and are fully recovered within two to three weeks. A mild residual cough after exercise can linger a little longer.
Isolate for at least a week after the cough stops — two is more responsible. Keep away from kennels, daycare, classes and busy parks, and tell anyone whose dog yours has recently been near.
Vaccination
The Bordetella vaccine, usually given intranasally or orally, plus parainfluenza in most core combination vaccines.
What to expect from it honestly:
- It does not guarantee prevention, because it covers only some of the organisms involved
- It does reduce the severity and duration of illness, and reduces shedding
- Immunity is relatively short — typically annual, sometimes six-monthly for high-risk dogs
- It needs giving at least a week or two before exposure
Most boarding kennels and daycare facilities require it, and that requirement is reasonable — it reduces the spread through a population even if it cannot protect every individual.
A mild cough or a sneeze for a few days after the intranasal vaccine is common and not a cause for concern.
What else causes a cough
Not every cough is kennel cough, and assuming it is delays diagnosis of things that matter:
- Heart disease — a soft, moist cough, often worse at night, with reduced exercise tolerance
- Collapsing trachea — a honking cough in small breeds, often triggered by excitement or a collar
- Lungworm — coughing with exercise intolerance, sometimes bleeding problems. Increasingly common in some regions and preventable with the right worming product
- Inhaled foreign body — sudden onset, often in a dog who was running in long grass
- Allergic airway disease
- Laryngeal paralysis — noisy breathing and a change in bark, mostly in older large breeds
A cough that lasts more than three weeks, or one in a dog who has not been near other dogs, deserves a proper workup rather than a wait.
