The impact of maternal pertussis vaccination recommendation on infant pertussis incidence and mortality in the USA: an interrupted time series analysis

Abstract Background Pertussis is a contagious respiratory disease. Maternal tetanus–diphtheria–acellular pertussis vaccination during pregnancy has been recommended by the United States Centres for Disease Control (US CDC) Advisory Committee on Immunization Practices (ACIP) for unvaccinated pregnant women since October 2011 to prevent infection among infants; in 2012, ACIP extended this recommendation to every pregnancy, regardless of previous vaccination status. The population-level effect of these recommendations on infant pertussis is unknown. This study aimed to examine the impact of the 2011/2012 ACIP pertussis recommendation on pertussis incidence and mortality among US infants. Methods We used monthly data on pertussis deaths among infants aged