{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T03:57:23Z","timestamp":1770782243410,"version":"3.50.0"},"reference-count":37,"publisher":"Oxford University Press (OUP)","issue":"1","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":34,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000925","name":"National Health and Medical Research Council","doi-asserted-by":"publisher","award":["APP1105905"],"award-info":[{"award-number":["APP1105905"]}],"id":[{"id":"10.13039\/501100000925","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,12,26]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The proportion of multidrug-resistant tuberculosis (MDR-TB) cases is increasing in Bhutan. We conducted the first retrospective genomic-epidemiological study to provide insights into the population structure, resistance patterns, and recent transmission in Bhutan.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Whole genome sequencing was performed on randomly selected drug-resistant (DR-TB) and drug-sensitive TB (DS-TB) isolates from Bhutan, collected between 2018 and 2022 at the Microbiological Diagnostic Unit Public Health Laboratory in Melbourne, Australia. Bioinformatic analysis was performed to identify drug-resistance mutations and genomic clustering of cases.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Approximately 40% of DR-TB and 2.5% of DS-TB were sequenced each year. Of the 203 sequences that passed the quality control, 126 (62.1%) were MDR-TB and 15 (7.4%) were isoniazid-resistant TB. There were 4 different circulating lineages, with the majority belonging to lineage 2 (86.2%). Using a SNP-threshold of \u226412 SNPs, 71% of sequences formed 12 genomic clusters; the largest comprised 88% of all MDR-TB sequences and spanned the entire study period and the country. These cases were highly clonal, with a mean pairwise SNP distance of 10 (range 0\u201325). Phylogenetic analysis with publicly available international sequence data showed that this MDR-TB cluster formed a distinct clade.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Contrary to current assumptions of repeat importations, the major burden of MDR-TB in Bhutan appears to be due to recent local transmission resulting in a large endemic cluster, advocating for targeted and enhanced contact tracing and screening for this MDR-TB clade. This study highlights the significant value of investing in TB genomics in resource-limited settings to gain actionable insights to inform policy decisions.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ofid\/ofaf802","type":"journal-article","created":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T12:42:32Z","timestamp":1767789752000},"source":"Crossref","is-referenced-by-count":1,"title":["Extensive Endemic Transmission of Multidrug-Resistant\n                    <i>Mycobacterium tuberculosis<\/i>\n                    in Bhutan: A Retrospective Genomic-Epidemiological Study"],"prefix":"10.1093","volume":"13","author":[{"given":"Thinley","family":"Dorji","sequence":"first","affiliation":[{"name":"Kanglung Hospital , Trashigang ,","place":["Bhutan"]},{"name":"Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity , Melbourne, Victoria 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Victorian Tuberculosis Program, Melbourne Health at the Peter Doherty Institute for Infection and Immunity, University of Melbourne , Melbourne, Victoria ,","place":["Australia"]},{"name":"Department of Infectious Diseases, University of Melbourne , Melbourne,Victoria ,","place":["Australia"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Norelle L","family":"Sherry","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity , Melbourne, Victoria ,","place":["Australia"]},{"name":"Microbiological Diagnostic Unit, Public Health Laboratory, Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity , Melbourne, Victoria ,","place":["Australia"]},{"name":"Department of Infectious Diseases & Immunology, Austin Health , Heidelberg, Victoria 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