Canine Respiratory Bordetellosis: Keeping up with an Evolving Pathogen

Introduction In light of advances in molecular microbiology and vaccinology it may seem surprising that Bordetella bronchiseptica (Bb) continues to be a significant respiratory tract pathogen in dogs. Improvements in the prevention and control of canine respiratory bordetellosis are within our reach, however, the scarcity of resources committed to this goal continues to be a problem. In this report, we provide a review of the clinical aspects of respiratory bordetellosis in dogs, discuss recent progress in understanding canine Bb at the molecular level, and consider particularly promising new approaches for reliable disease prevention. Canine respiratory bordetellosis was first recognized in association with epizootics of canine distemper that occurred in the early 1900's. Despite the availability of several types of vaccines, Bb continues to be a major cause of canine respiratory disease. This was particularly evident throughout 1999 when outbreaks of respiratory tract disease (Kennel Cough) plagued racing Greyhounds even though the racing Greyhound industry has rigorous vaccination policies to prevent infectious respiratory tract disease. Conservative estimates place 1999 Greyhound racing revenue losses associated with this disease complex in the millions of dollars. Less dramatic but nevertheless significant disease outbreaks are a relatively common occurrence in boarding kennels, animal shelters, research facilities, and veterinary clinics. Our studies, as well as the experience of veterinarians and dog owners, leave little doubt that current vaccines do not adequately protect dogs against bordetellosis.