HUMAN BORDETELLA-BRONCHISEPTICA INFECTION RELATED TO CONTACT WITH INFECTED ANIMALS - PERSISTENCE OF BACTERIA IN HOST

Within a period of 2 1/2 years, Bordetella bronchiseptica was isolated four times from a 79-year-old woman with bronchopneumonia, We have de monstrated by pulsed-field gel electrophoresis that this infection was related tb contact with infected rabbits. The initial human B. bronch iseptica isolate had a phenotype characteristic of usual B. bronchisep tica clinical isolates; it produced toxin and adhesins, such as adenyl ate cyclase-hemolysin, filamentous hemagglutinin, and pertactin, and w as able to induce lethality in a murine respiratory model. By contrast , although the three successive human isolates produced adhesins, they did not express adenylate cyclase-hemolysin and were unable to induce lethality. This implies that adenylate cyclase-hemolysin is required to induce lethality We suggest that B. bronchispetica may persist in t he host, with expression of adenylate cyclase-hemolysin being essentia l for the initiation of infection and expression of adhesins being ess ential for persistence.