This may account for some additional false positivity owing to persistence of IgM antibodies following previous infections. Similar observation of poor specificity of an anti-Leptospira IgM rapid assay was reported in Vietnam where a high proportion of clinically well individuals gave find protocol positive IgM results. 5 This study suggests that the diagnostic accuracy of this ELISA for diagnosis of acute leptospirosis in Laos

is improved when the diagnostic cut-off is optimised using ROC curve analysis compared with that provided in the manufacturer’s instructions. Further studies are required to determine the utility of this assay for acute diagnosis and epidemiology in other leptospirosis-endemic and non-endemic settings as it is likely that such ‘tuning’ of ELISA

cut-offs is needed in different epidemiological settings. Further studies are also required to determine the diagnostic utility of this and other such assays as simply antibody detection tools for application in epidemiological surveillance. There is a clear need for implementation and local validation of new serological assays and PCRs for acute diagnosis of leptospirosis SCH772984 cell line infection. PNN, SDB and AT conceived and designed the study; SDB, AT, MV, VD, OL, LS, RH and MD analysed and interpreted the data; SDB, AT and PNN drafted the manuscript. All authors critically revised the manuscript for intellectual content and read and approved the final version. SDB and PNN are guarantors of the paper. Wellcome Trust of Great Britain; Embassy Small Grants Scheme. None declared. The ELISA tests were provided without charge by Standard Diagnostics (Yongin-si, South Korea). Standard Diagnostics had no

role in the design, execution, analysis, writing or submission of this paper. Ethical approval was granted by the Ethical Review Committee of the Faculty of Medical Sciences, National University of Laos, Vientiane, Laos. The authors O-methylated flavonoid are very grateful to all the patients who participated in this study as well as the doctors, nurses and staff of the microbiology laboratory, especially Rattanaphone Phetsouvanh, Mayfong Mayxay, Anisone Changthongthip, Soulignasack Thongpaseuth and Simaly Phongmany, Valy Keoluangkot and the staff of the Adult Infectious Disease Ward. The authors also thank Profs. Chanpheng Thammavong and Bounkong Syhavong, the Minister of Health, His Excellency Dr Ponmek Dalaloy and the Director of the Curative Department, Ministry of Health, Prof. Sommone Phounsavath for their support for this study, which was part of the Wellcome Trust–Mahosot Hospital–Oxford Tropical Medicine Research Collaboration funded by the Wellcome Trust of Great Britain. The authors are very grateful to the British Embassy, Bangkok, and His Excellency the British Ambassador to the Lao PDR for additional financial support under the Embassy Small Grants Scheme.