A qPCR assay for Bordetella pertussis cells that enumerates both live and dead bacteria

Abstract

<jats:title>Abstract</jats:title><jats:p><jats:italic>Bordetella pertussis</jats:italic> is the causative agent of whooping cough, commonly referred to as pertussis. Although the incidence of pertussis was reduced through vaccination, during the last thirty years it has returned to high levels in a number of countries. This resurgence has been linked to the switch from the use of whole-cell to acellular vaccines. Protection afforded by acellular vaccines appears to be short-lived compared to that afforded by whole cell vaccines. In order to inform future vaccine improvement by identifying immune correlates of protection, a human challenge model of <jats:italic>B. pertussis</jats:italic> colonisation has been developed. Accurate measurement of colonisation status in this model has required development of a qPCR-based assay to enumerate <jats:italic>B. pertussis</jats:italic> in samples that distinguishes between viable and dead bacteria. Here we report the development of this assay and its performance in the quantification of <jats:italic>B. pertussis</jats:italic> from human challenge model samples. This assay has future utility in diagnostic labs and in research where a quantitative measure of both <jats:italic>B. pertussis</jats:italic> number and viability is required.</jats:p>