Maternal Pertussis Wholecell Responses

Pertussis is resurging worldwide. In Africa alone it is estimated that there are 2.1 million cases and 542,000 deaths from pertussis in infants under 1 year with the highest rates of morbidity and mortality in infants \<3 months old, before possible prevention via the infant immunization programme1. To protect these most vulnerable infants, the World Health Organisation (WHO) recommends Tdap vaccination as safe in pregnancy and recommends the use of wP vaccines within the EPI. Maternal antibody following aP vaccination can interfere with infant anti-pertussis antibody responses post infant EPI vaccination, which is of concern in high burden settings such as Uganda. There are therefore multiple factors in this population which may influence the effect of pertussis immunization in pregnancy, and which have not been studied, most notably HIV infection and interference with wP vaccines in infants. The immunogenicity of Tdap in HIV-infected pregnant women has not yet been examined. In addition, to date, the effect of maternal vaccination, placental transfer and infant antibody responses in HEU infants have not been studied at all. There are no studies examining the immune response to wP vaccine administered to infants (EPI recommendation) whose mothers received aP in pregnancy.