Kennel cough (canine infectious tracheobronchitis)
Contagious respiratory illness in dogs caused by Bordetella, parainfluenza, and sometimes other pathogens. Like a "common cold" — usually self-limiting.
Kennel cough is a viral and bacterial respiratory infection complex, most commonly involving Bordetella bronchiseptica and canine parainfluenza virus. It is highly contagious, spreads through respiratory droplets and shared surfaces, and outbreaks are common where dogs gather (boarding kennels, daycare, shows, parks, vets' waiting rooms).
The classic sign is a dry honking cough, often described as sounding like the dog is choking. Some dogs have mild nasal discharge or low energy; most stay bright and eat well. Onset is typically 3–10 days after exposure.
Most cases self-limit in 1–3 weeks. Antibiotics are reserved for cases with fever, lethargy, decreased appetite, or productive cough — a vet decides. Cough suppressants are sometimes prescribed.
Vaccination (Bordetella, often combined with parainfluenza) is non-core but strongly recommended for any dog that boards, attends daycare, goes to shows, or frequents busy dog parks. Vaccines do not prevent all cases (the syndrome includes pathogens not in vaccines) but reduce severity and incidence.
Highly contagious for 1–3 weeks after symptoms start — isolate from other dogs through that window, including beyond when your dog personally feels better.