Orientia, rickettsia, and leptospira pathogens as causes of CNS infections in Laos: a prospective study by Dittrich, S, Rattanavong, S, Lee, SJ, Panyanivong, P, Craig, SB, Tulsiani, SM, Blacksell, SD, Dance, DAB, Dubot-Pérès, A, Sengduangphachanh, A, Phoumin, P, Paris, DH, Newton, PN