Persistent Bordetella Bronchiseptica Pneumonia in an Immunocompetent Infant and Genetic Comparison of Clinical Isolates with Kennel Cough Vaccine Strains

An infant who experienced recurrent episodes of respiratory failure received a diagnosis of pertussis on the basis of immunofluorescence testing, but culture revealed macrolide-resistant Bordetella bronchiseptica. Genetic analysis demonstrated that the child was not infected with a kennel cough vaccine strain, although the family's dog had recently been vaccinated. The infection cleared with imipenem therapy.