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Bull PC, Kortok M, Kai O, Ndungu F, Ross A, Lowe BS, Newbold CI, Marsh K.Bull PC, et al.J Infect Dis. 2000 Jul;182(1):252-9. doi: 10.1086/315652. Epub 2000 Jun 30.J Infect Dis. 2000.PMID: 10882604