Fig. 1

Serotype-specific pneumococcal carriage in Malawian children, determined by microarray. A total of 179 pneumococcal strains were detected from 116 nasopharyngeal swabs, comprising 43 distinct pneumococcal serotypes and non-typeable strains (NT). The blue and red bar graphs represent serotypes detected in HIV positive and HIV negative children respectively. The serotypes were classified as Vaccine Type and Non-Vaccine Type. The non-vaccine serotypes were subdivided into high (Non-Vaccine Type (*)) and low (Non-Vaccine Type (**)) invasive potential based on the global frequency of isolation from invasive disease [24]. Individuals carrying multiple serotypes are represented more than once. The line graph represents cumulative frequency of serotypes isolated and was used to estimate the proportion of Vaccine Type (60 %) and Non-Vaccine Type (40 %)