Reduced pertussis disease severity in infants following the introduction of pertussis vaccination of pregnant women in Spain, 2015–2019

Maternal pertussis vaccination during the third trimester of pregnancy was implemented in 2015 in Spain, reaching a national coverage of 84% in 2019. In this ecological study, we investigated whether there was a change in the disease severity for pertussis in infants upon introduction of prenatal pertussis vaccination.