Abstract
Melioidosis is a disease of significant public health importance that is being increasingly recognized globally. The majority of cases arise through direct percutaneous exposure to its etiological agent, Burkholderia pseudomallei. In the Lao People’s Democratic Republic (Laos), the presence and environmental distribution of B. pseudomallei are not well characterized, though recent epidemiological surveys of the bacterium have indicated that B. pseudomallei is widespread throughout the environment in the center and south of the country and that rivers can act as carriers and potential sentinels for the bacterium. The spatial and genetic distribution of B. pseudomallei strains within Vientiane Capital, where the majority of cases diagnosed to date have originated, remains an important knowledge gap. We sampled surface runoff from drain catchment areas throughout urban Vientiane to determine the presence and local population structure of the bacterium. B. pseudomallei was detected in drainage areas throughout the capital, indicating that it is widespread in the environment and that exposure rates in urban Vientiane are likely higher than previously thought. Whole-genome comparative analysis demonstrated that Lao B. pseudomallei isolates are highly genetically diverse, suggesting that the bacterium is well established and not a recent introduction. Despite the wide genome diversity, one environmental survey isolate was highly genetically related to a Lao melioidosis patient isolate collected 13 years prior to the study. Knowledge gained from this study will augment understanding of B. pseudomallei phylogeography in Asia and enhance public health awareness and future implementation of infection control measures within Laos.
| Original language | English |
|---|---|
| Article number | e02112-20 |
| Pages (from-to) | 1-16 |
| Number of pages | 16 |
| Journal | Applied and Environmental Microbiology |
| Volume | 87 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Feb 2021 |
Bibliographical note
Funding Information:This study was supported by grants from the Australian National Health and Medical Research Council (grant numbers 1046812, 1098337, and 1131932 [The HOT NORTH initiative]). A.R. is supported by a Charles Darwin University International Ph.D. scholarship. D.A.B.D. was supported by the Wellcome Trust (grant number 106698/Z/ 14/Z).
Funding Information:
We thank the Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU) and Mahosot Hospital Microbiology staff for their advice and support in undertaking this investigation, particularly Anisone Chanthongthip and Sengkham Simanivong. Additionally, we thank the microbiology staff at Menzies School of Health and Research for their assistance with culture and processing of samples, especially Vanessa Rigas. We are grateful to Paul Newton, director of LOMWRU, Manivanh Vongsouvath, head of the Mahosot Hospital Microbiology Laboratory, the staff at the Ministry of Health, the University of Health Sciences, and the directors of Mahosot Hospital for their support of this study and the work of LOMWRU. The study was conceptualized by A.R., M.M., M.K., D.A.B.D., and B.J.C. Funding was acquired by B.J.C. and D.A.B.D. Data collection was undertaken by A.R., M.L., and S.R. Formal analysis was done by A.R., M.K., and J.R.W. A.R. wrote the original draft, and M.K., B.J.C., M.M., J.R.W., and D.A.B.D. revised and edited the manuscript. All authors saw and approved the final version. None of the authors have any conflicts of interest to declare. This study was supported by grants from the Australian National Health and Medical Research Council (grant numbers 1046812, 1098337, and 1131932 [The HOT NORTH initiative]). A.R. is supported by a Charles Darwin University International Ph.D. scholarship. D.A.B.D. was supported by the Wellcome Trust (grant number 106698/Z/ 14/Z). This study was approved by the Lao National Ethics Committee for Health Research (2018.32.MC) and the Menzies School of Health Research (HREC 02/38). Sample site approval was obtained by local Lao landowners before survey commencement.
Publisher Copyright:
© 2021 Rachlin et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
