How well do vaccines for Bordetella bronchiseptica work in dogs? A critical review of the literature 1977-2014

- Many studies on the efficacy of vaccines for Bordetella bronchiseptica have flaws in experimental design.
- A failure to consider pen effect is a common flaw, and has implications for statistical analyses.
- Data from laboratory studies and field trials document efficacy of intranasal, parenteral and oral Bb vaccines in disease reduction.
- Optimal protocols to engender long-term immunological memory and extend longevity of clinical immunity remain unresolved.

Bordetella bronchiseptica (Bb) has long been causally associated with respiratory disease in dogs. Parenteral and intranasal vaccines for this pathogen have been in common use since their development in the late 1970s and early 1980s and recently a commercial oral Bb vaccine has become available. Overall, the literature (comprising experimental infection models and field studies) documents the efficacy of these vaccines in stimulating disease-sparing mucosal and systemic immune responses that can be associated with reduced growth of Bb in vivo. However, many of the published studies are limited by flaws in experimental design, most notably a failure to consider the biological and statistical implications of the 'pen effect'. Many questions related to the longevity of vaccine induced immunity against Bb and the impact of natural exposure on herd immunity remain unanswered.