Protocol for a phase IV double-blind randomised controlled trial to investigate the effect of the 13-valent pneumococcal conjugate vaccine and the 23-valent pneumococcal polysaccharide vaccine on pneumococcal colonisation using the experimental human pneumococcal challenge model in healthy adults (PREVENTING PNEUMO 2).

Liatsikos K, Hyder-Wright A, Pojar S, Chen T, Wang D, Davies K, Myerscough C, Reine J, Robinson RE, Urban B, Mitsi E, Solorzano C, Gordon SB, Quinn A, Pan K, Anderson AS, Theilacker C, Begier E, Gessner BD, Collins A, Ferreira DM, PNEUMO 2 study group,

Malawi Liverpool Wellcome Programme