Charitha Mendis1, Vasanthi Thevanesam2, Athula Kumara2, Susiji Wickramasinghe3, Dushantha Madegedara4, Chandika Gamage2, Stephen V Gordon5, Yasuhiko Suzuki6, Champa Ratnatunga7, Chie Nakajima8. 1. Division of Bioresources, Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan; Department of Medical Laboratory Science, Faculty of Allied Health Sciences, University of Peradeniya, Sri Lanka. 2. Department of Microbiology, Faculty of Medicine, University of Peradeniya, Sri Lanka. 3. Department of Parasitology, Faculty of Medicine, University of Peradeniya, Sri Lanka. 4. Respiratory Disease Treatment Unit, Teaching Hospital, Kandy, Sri Lanka. 5. School of Veterinary Medicine, University College Dublin, Belfield, Dublin, Ireland; Global Station for Zoonosis Control, Hokkaido University Global Institute for Collaborative Research and Education, Sapporo, Japan. 6. Division of Bioresources, Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan; Global Station for Zoonosis Control, Hokkaido University Global Institute for Collaborative Research and Education, Sapporo, Japan. 7. Department of Microbiology, Faculty of Medicine, University of Peradeniya, Sri Lanka. Electronic address: medmicropera@pdn.ac.lk. 8. Division of Bioresources, Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan; Global Station for Zoonosis Control, Hokkaido University Global Institute for Collaborative Research and Education, Sapporo, Japan. Electronic address: cnakajim@czc.hokudai.ac.jp.
Abstract
OBJECTIVE: Sri Lanka is a country where the molecular epidemiology of Mycobacterium tuberculosis (MTB) is poorly explored. Therefore, this study was performed to identify circulating lineages/sub-lineages of MTB and their transmission patterns. METHODS: DNA was extracted from 89 isolates of MTB collected during 2012 and 2013 from new pulmonary tuberculosis patients in Kandy, Sri Lanka and analyzed by spoligotyping, large sequence polymorphism (LSP), mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing, and drug resistance-associated gene sequencing. RESULTS: The predominant lineage was lineage 4 (Euro-American, 45.9%), followed by lineage 1 (Indo-Oceanic, 29.4%), lineage 2 (East-Asian, 23.5%), and lineage 3 (Central-Asian, 1.2%). Among 26 spoligotype patterns, eight were undesignated or new types and seven of these belonged to lineage 4. Undesignated lineage 4/SIT124 (n=2/8) and SIT3234 (n=8/8) clustered together based on 24-locus MIRU-VNTR typing. The dominant sub-lineage was Beijing/SIT1 (n=19), with the isoniazid resistance katG G944C mutation (Ser315Thr) detected in two of them. CONCLUSIONS: The population structure of MTB in Kandy, Sri Lanka was different from that in the South Asian region. The clonal expansion of locally evolved lineage 4/SIT3234 and detection of the pre-multidrug resistant Beijing isolates from new tuberculosis patients is alarming and will require continuous monitoring.
OBJECTIVE:Sri Lanka is a country where the molecular epidemiology of Mycobacterium tuberculosis (MTB) is poorly explored. Therefore, this study was performed to identify circulating lineages/sub-lineages of MTB and their transmission patterns. METHODS: DNA was extracted from 89 isolates of MTB collected during 2012 and 2013 from new pulmonary tuberculosispatients in Kandy, Sri Lanka and analyzed by spoligotyping, large sequence polymorphism (LSP), mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing, and drug resistance-associated gene sequencing. RESULTS: The predominant lineage was lineage 4 (Euro-American, 45.9%), followed by lineage 1 (Indo-Oceanic, 29.4%), lineage 2 (East-Asian, 23.5%), and lineage 3 (Central-Asian, 1.2%). Among 26 spoligotype patterns, eight were undesignated or new types and seven of these belonged to lineage 4. Undesignated lineage 4/SIT124 (n=2/8) and SIT3234 (n=8/8) clustered together based on 24-locus MIRU-VNTR typing. The dominant sub-lineage was Beijing/SIT1 (n=19), with the isoniazid resistance katG G944C mutation (Ser315Thr) detected in two of them. CONCLUSIONS: The population structure of MTB in Kandy, Sri Lanka was different from that in the South Asian region. The clonal expansion of locally evolved lineage 4/SIT3234 and detection of the pre-multidrug resistant Beijing isolates from new tuberculosis patients is alarming and will require continuous monitoring.
Authors: Benjamin D Thumamo Pokam; D Yeboah-Manu; P M Teyim; P W Guemdjom; B Wabo; A B D Fankep; R E Okonu; Anne E Asuquo Journal: J Clin Tuberc Other Mycobact Dis Date: 2020-09-01