The article reports on a study conducted in Poland between 2009 and 2011 to estimate the incidence of whooping cough caused by Bordetella parapertussis, a bacterium closely related to the agent of pertussis. The study showed that parapertussis is not routinely diagnosed in Poland and estimated an incidence of 39 cases per 100,000 person‑years. The highest incidence rates were observed among children aged 3–5 years and adults over 60 years. Young age, older age, and crowded living conditions were associated with an increased likelihood of diagnosis. The findings supported prioritizing laboratory testing for parapertussis in preschool children and women over 40 presenting with prolonged cough, and suggested considering post‑exposure prophylaxis for close contacts of confirmed cases.
This analysis, based on data from a previously published large‑scale epidemiological study of pertussis, was carried out by Rysard, an EPIET fellow based in Warsaw. I was particularly grateful for his work on this analysis, as the original study was a major undertaking and initially resulted in publications focusing only on pertussis.