Understanding the role of bacterial density and multiplicity of carriage and other carriage characteristics in the transmission of S. pneumoniae

Principal Investigator: Neil French
Institution: Malawi-Liverpool-Wellcome Trust, University of Liverpool
Co-Investigators: Stefan Flasche, Stephane Hue, Todd Swarthout, Kondwani Jambo


Despite extensive carriage surveys, it is challenging to directly measure pneumococcal transmission in endemic population. Recent work by Flasche and Hue suggests that genomic distance of isolates can be used to infer transmission. This study will leverage data from a longitudinal study of infants and their household in Karonga, rural northern Malawi (https://academic.oup.com/aje/article-lookup/doi/10.1093/aje/kwv134) to better understand the characteristics associated with transmission. Confirming the value of the novel genomic approach and applying it to the Malawi dataset will improve classification of transmission events, thereby increasing the power of a standard risk factor study to identify factors associated with promoting transmission. This study will first focus on two measurable and potentially modifiable transmission factors – bacterial density in carriers and multiplicity of carriage.