The landscape of paediatric infectious disease exposure in a rural sub-Saharan Africa setting in Kilifi, Kenya: longitudinal serological analysis over two decades and priorities for future vaccine development

BackgroundThe paucity of data on the contemporary causes of serious infection among the worlds most vulnerable children means the landscape of emerging paediatric infectious disease remains largely undefined and out of focus on the global vaccine research and development agenda. MethodsWe aimed to partially define the paediatric infectious disease landscape in a typical low-income setting in sub-Saharan Africa in Kilifi, Kenya by simultaneously estimating antibody prevalence for 38 infectious diseases using a longitudinal birth cohort that was sampled between 2002 and 2008 and a paediatric inpatient cohort that was sampled between 2006 and 2017. FindingsAmong the infectious diseases with the highest antibody prevalence in the first year of life were vaccine-preventable diseases such as RSV (57.4%), mumps (31.5%) and influenza H3N2 (37.3%). Antibody prevalence for Plasmodium falciparum shifted substantially over time, from 47% in the mid 2000s to 13% approximately 10 years later corresponding to a documented decline in parasite transmission. A high prevalence of antibodies was also observed in the first year of life for infections for which no licenced vaccines are currently available, including norovirus (34.2%), cytomegalovirus (44.7%), EBV (29.3%) and coxsackie B virus (40.7%). The prevalence to antibodies to vaccine antigens in the local immunisation schedule was generally high but varied by antigen. InterpretationThe data show a high and temporally stable infection burden of RSV, mumps and influenza, providing a compelling evidence base to support progress towards the introduction of these vaccines into the local immunization schedule. The high prevalence of norovirus, EBV, CMV and Coxsackie B provide rationale for increased vaccine research and development investment. FundingThis research was funded by the Wellcome Trust (grant no. WT105882MA).