Statistical analysis and modelling of the effect of conjugate vaccine and systemic capsular antibody on carriage and transmission of Streptococcus pneumoniae in Kenyan children. (360G-Wellcome-092767_Z_10_Z)

The indirect effects of conjugate vaccines have varied markedly in different populations with profound implications for the total effectiveness of each programme. This research project aims to analyse the relationship between vaccination with pneumococcal conjugate vaccine (PCV) and nasopharyngeal carriage of vaccine and non-vaccine strains, and to analyse the effect of serotype-specific antibody concentrations on prevalent and incident homologous nasopharyngeal carriage. These analyses will generate parameters which can be used in models recently developed within the PneumoCarr consortium for evaluating the population effects of vaccine in settings similar to Kenya. They will also aid in validating and extending these models for application in developing country settings. To achieve these objectives, the research project will first analyse data from four studies carried out in Kilifi, Kenya. Next, the parameters obtained from these studies will be used to model the impact of PCV on pneumococcal transmission and disease using well developed modelling structures. As the vaccine is being introduced in Kenya in the third quarter of 2010, and as the effectiveness of PCV introduction is being monitored in a specific study in Kilifi, the validity of the model predictions can be tested with time against the epidemiological observations.