The immunological basis for immunization series: module 4: pertussis, update 2017

Overview

Bordetella pertussis is a strictly human pathogen with multiple biological activities. The bacteria are transmitted by droplets and the infectious dose is small in immunologically naïve patients. Pertussis infection begins with the attachment of B. pertussis to the ciliated epithelium of the respiratory tract; the subsequent manifestations are thought to be the result of the interplay between various virulence factors (toxins and adhesins) of the organism (Table 1). Irrespective of high vaccination coverage in infants and toddlers, B. pertussis circulates in all countries; reinfections are common and occur throughout a person’s lifetime.

The genomes of the three classical Bordetella species – B. pertussis, B. parapertussis and B. bronchiseptica – as well as of some other Bordetella spp. have been sequenced and are publicly available (Parkhill et al., 2003; Sebaihia et al., 2006; Bouchez & Guiso, 2013; Harvill et al., 2014; Gross et al., 2008). B. pertussis and B. parapertussis appear to have emerged relatively recently from a common B. bronchiseptica-like ancestor (Diavatopoulos et al., 2005). Changes in virulence factor expression in Bordetella spp. have also been studied at the genomic level (Linz et al., 2016).