The 327 Leptospira spp. used in this study are listed in Table S1 . Genomic DNA was extracted as described previously [20] (link), with the exception of isolates from the National Center for Emerging and Zoonotic Infectious Diseases, Centers for Diseases Control and Prevention, USA, which were extracted with the addition of dimethyl sulfoxide. For isolates for which the species was unknown, identification was undertaken by amplification and sequencing of the near full-length 16S rRNA gene (rrs), as described previously [20] (link). Sequence data for rrs has been deposited in GenBank (see Table S2 for accession numbers). The serovars of isolates from recent human leptospirosis cases in Thailand, Laos and Sri Lanka were determined by the WHO/FAO/OIE Collaborating Center for Reference and Research on Leptospirosis, Queensland Health Forensic and Scientific Services, Brisbane, Australia using the cross-agglutinin absorption test (CAAT). The serovars of contemporary isolates from China were determined using CAAT at the China Medical Culture Collection of National Institutes for Food and Drug Control, China.
Ethical approvals to obtain contemporary clinical isolates of Leptospira spp. are as follows. Isolates from patients in northeast Thailand between October 2000 and December 2006 were obtained during a prospective study of acute febrile illness [20] (link), which was approved by the Ethical Committee of the Ministry of Public Health, Royal Government of Thailand. Isolates from patients in Laos between August 2006 and October 2009 were obtained during a prospective fever study approved by the Oxford Tropical Research Ethics Committee (OXTREC) and the National Ethics Committee for Health Research (NECHR), Ministry of Health, Government of Lao PDR. Isolates obtained from patients in Sri Lanka between June 2006 and May 2007 were obtained during a prospective fever study approved by the Research Ethics Committee of the Liverpool School of Tropical Medicine, UK and the Ethical Review Committee of the Faculty of Medicine of the University of Kelaniya, Sri Lanka. Written informed consent was obtained from all subjects except where not required (not required for data analyzed anonymously in Laos PDR at the time of the study). Other clinical isolates were obtained from the China Medical Culture Collection of National Institutes for Food and Drug Control, China, and the National Center for Emerging and Zoonotic Infectious Diseases, Centers for Diseases Control and Prevention, USA. All data were analyzed anonymously.
Ethical approvals to obtain contemporary clinical isolates of Leptospira spp. are as follows. Isolates from patients in northeast Thailand between October 2000 and December 2006 were obtained during a prospective study of acute febrile illness [20] (link), which was approved by the Ethical Committee of the Ministry of Public Health, Royal Government of Thailand. Isolates from patients in Laos between August 2006 and October 2009 were obtained during a prospective fever study approved by the Oxford Tropical Research Ethics Committee (OXTREC) and the National Ethics Committee for Health Research (NECHR), Ministry of Health, Government of Lao PDR. Isolates obtained from patients in Sri Lanka between June 2006 and May 2007 were obtained during a prospective fever study approved by the Research Ethics Committee of the Liverpool School of Tropical Medicine, UK and the Ethical Review Committee of the Faculty of Medicine of the University of Kelaniya, Sri Lanka. Written informed consent was obtained from all subjects except where not required (not required for data analyzed anonymously in Laos PDR at the time of the study). Other clinical isolates were obtained from the China Medical Culture Collection of National Institutes for Food and Drug Control, China, and the National Center for Emerging and Zoonotic Infectious Diseases, Centers for Diseases Control and Prevention, USA. All data were analyzed anonymously.
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