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Bagheri M, Pormohammad A, Fardsanei F, Yadegari A, Arshadi M, Deihim B, Hajikhani B, Turner RJ, Khalili F, Mousavi SMJ, Dadashi M, Goudarzi M, Dabiri H, Goudarzi H, Mirsaeidi M, Nasiri MJ. Diagnostic Accuracy of Pyrazinamide Susceptibility Testing in Mycobacterium tuberculosis: A Systematic Review with Meta-Analysis. Microb Drug Resist 2021; 28:87-98. [PMID: 34582723 DOI: 10.1089/mdr.2021.0048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Introduction: Pyrazinamide (PZA) susceptibility testing plays a critical role in determining the appropriate treatment regimens for multidrug-resistant tuberculosis. We conducted a systematic review and meta-analysis to evaluate the diagnostic accuracy of sequencing PZA susceptibility tests against culture-based susceptibility testing methods as the reference standard. Methods: We searched the MEDLINE/PubMed, Embase, and Web of Science databases for the relevant records. The QUADAS-2 tool was used to assess the quality of the studies. Diagnostic accuracy measures (i.e., sensitivity and specificity) were pooled with a random-effects model. All statistical analyses were performed with Meta-DiSc (version 1.4, Cochrane Colloquium, Barcelona, Spain), STATA (version 14, Stata Corporation, College Station, TX), and RevMan (version 5.3, The Nordic Cochrane Centre, the Cochrane Collaboration, Copenhagen, Denmark) software. Results: A total of 72 articles, published between 2000 and 2019, comprising data for 8,701 isolates of Mycobacterium tuberculosis were included in the final analysis. The pooled sensitivity and specificity of the PZA sequencing test against all reference tests (the combination of BACTEC mycobacteria growth indicator tube 960 (MGIT 960), BACTEC 460, and proportion method) were 87% (95% CI: 85-88) and 94.7% (95% CI: 94-95). The positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the area under the curve estimates were found to be 12.0 (95% CI: 9.0-16.0), 0.17 (95% CI: 0.13-0.21), 106 (95% CI: 71-158), and 96%, respectively. Deek's test result indicated a low likelihood for publication bias (p = 0.01). Conclusions: Our analysis indicated that PZA sequencing may be used in combination with conventional tests due to the advantage of the time to result and in scenarios where culture tests are not feasible. Further work to improve molecular tests would benefit from the availability of standardized reference standards and improvements to the methodology.
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Affiliation(s)
- Mohammad Bagheri
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ali Pormohammad
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Fatemeh Fardsanei
- Medical Microbiology Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Ali Yadegari
- School of Medicine, Mazandaran University of Medical Sciences, Mazandaran, Iran
| | - Maniya Arshadi
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Behnaz Deihim
- Department of Bacteriology and Virology, School of Medicine, Dezful University of Medical Sciences, Dezful, Iran
| | - Bahareh Hajikhani
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ray J Turner
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Farima Khalili
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Masoud Dadashi
- Department of Microbiology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran
| | - Mehdi Goudarzi
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hossein Dabiri
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hossein Goudarzi
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehdi Mirsaeidi
- Division of Pulmonary and Critical Care, College of Medicine-Jacksonville, University of Florida, Jacksonville, FL, USA
| | - Mohammad Javad Nasiri
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Shockey AC, Dabney J, Pepperell CS. Effects of Host, Sample, and in vitro Culture on Genomic Diversity of Pathogenic Mycobacteria. Front Genet 2019; 10:477. [PMID: 31214242 PMCID: PMC6558051 DOI: 10.3389/fgene.2019.00477] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 05/03/2019] [Indexed: 12/16/2022] Open
Abstract
Mycobacterium tuberculosis (M. tb), an obligate human pathogen and the etiological agent of tuberculosis (TB), remains a major threat to global public health. Comparative genomics has been invaluable for monitoring the emergence and spread of TB and for gaining insight into adaptation of M. tb. Most genomic studies of M. tb are based on single bacterial isolates that have been cultured for several weeks in vitro. However, in its natural human host, M. tb comprises complex, in some cases massive bacterial populations that diversify over the course of infection and cannot be wholly represented by a single genome. Recently, enrichment via hybridization capture has been used as a rapid diagnostic tool for TB, circumventing culturing protocols and enabling the recovery of M. tb genomes directly from sputum. This method has further applicability to the study of M. tb adaptation, as it enables a higher resolution and more direct analysis of M. tb genetic diversity within hosts with TB. Here we analyzed genomic material from M. tb and Mycobacterium bovis populations captured directly from sputum and from cultured samples using metagenomic and Pool-Seq approaches. We identified effects of sampling, patient, and sample type on bacterial genetic diversity. Bacterial genetic diversity was more variable and on average higher in sputum than in culture samples, suggesting that manipulation in the laboratory reshapes the bacterial population. Using outlier analyses, we identified candidate bacterial genetic loci mediating adaptation to these distinct environments. The study of M. tb in its natural human host is a powerful tool for illuminating host pathogen interactions and understanding the bacterial genetic underpinnings of virulence.
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Affiliation(s)
- Abigail C. Shockey
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
| | - Jesse Dabney
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Caitlin S. Pepperell
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
- Department of Medicine, Division of Infectious Diseases, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
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Shaweno D, Karmakar M, Alene KA, Ragonnet R, Clements AC, Trauer JM, Denholm JT, McBryde ES. Methods used in the spatial analysis of tuberculosis epidemiology: a systematic review. BMC Med 2018; 16:193. [PMID: 30333043 PMCID: PMC6193308 DOI: 10.1186/s12916-018-1178-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 09/20/2018] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Tuberculosis (TB) transmission often occurs within a household or community, leading to heterogeneous spatial patterns. However, apparent spatial clustering of TB could reflect ongoing transmission or co-location of risk factors and can vary considerably depending on the type of data available, the analysis methods employed and the dynamics of the underlying population. Thus, we aimed to review methodological approaches used in the spatial analysis of TB burden. METHODS We conducted a systematic literature search of spatial studies of TB published in English using Medline, Embase, PsycInfo, Scopus and Web of Science databases with no date restriction from inception to 15 February 2017. The protocol for this systematic review was prospectively registered with PROSPERO ( CRD42016036655 ). RESULTS We identified 168 eligible studies with spatial methods used to describe the spatial distribution (n = 154), spatial clusters (n = 73), predictors of spatial patterns (n = 64), the role of congregate settings (n = 3) and the household (n = 2) on TB transmission. Molecular techniques combined with geospatial methods were used by 25 studies to compare the role of transmission to reactivation as a driver of TB spatial distribution, finding that geospatial hotspots are not necessarily areas of recent transmission. Almost all studies used notification data for spatial analysis (161 of 168), although none accounted for undetected cases. The most common data visualisation technique was notification rate mapping, and the use of smoothing techniques was uncommon. Spatial clusters were identified using a range of methods, with the most commonly employed being Kulldorff's spatial scan statistic followed by local Moran's I and Getis and Ord's local Gi(d) tests. In the 11 papers that compared two such methods using a single dataset, the clustering patterns identified were often inconsistent. Classical regression models that did not account for spatial dependence were commonly used to predict spatial TB risk. In all included studies, TB showed a heterogeneous spatial pattern at each geographic resolution level examined. CONCLUSIONS A range of spatial analysis methodologies has been employed in divergent contexts, with all studies demonstrating significant heterogeneity in spatial TB distribution. Future studies are needed to define the optimal method for each context and should account for unreported cases when using notification data where possible. Future studies combining genotypic and geospatial techniques with epidemiologically linked cases have the potential to provide further insights and improve TB control.
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Affiliation(s)
- Debebe Shaweno
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia.
- Victorian Tuberculosis Program at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia.
| | - Malancha Karmakar
- Victorian Tuberculosis Program at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Victoria, Australia
| | - Kefyalew Addis Alene
- Research School of Population Health, College of Health and Medicine, The Australian National University, Canberra, Australia
- Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Romain Ragonnet
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
- Burnet Institute, Melbourne, Australia
| | | | - James M Trauer
- Victorian Tuberculosis Program at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia
| | - Justin T Denholm
- Victorian Tuberculosis Program at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Victoria, Australia
| | - Emma S McBryde
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, Queensland, Australia
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Brynildsrud OB, Pepperell CS, Suffys P, Grandjean L, Monteserin J, Debech N, Bohlin J, Alfsnes K, Pettersson JOH, Kirkeleite I, Fandinho F, da Silva MA, Perdigao J, Portugal I, Viveiros M, Clark T, Caws M, Dunstan S, Thai PVK, Lopez B, Ritacco V, Kitchen A, Brown TS, van Soolingen D, O’Neill MB, Holt KE, Feil EJ, Mathema B, Balloux F, Eldholm V. Global expansion of Mycobacterium tuberculosis lineage 4 shaped by colonial migration and local adaptation. SCIENCE ADVANCES 2018; 4:eaat5869. [PMID: 30345355 PMCID: PMC6192687 DOI: 10.1126/sciadv.aat5869] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 09/11/2018] [Indexed: 05/23/2023]
Abstract
On the basis of population genomic and phylogeographic analyses of 1669 Mycobacterium tuberculosis lineage 4 (L4) genomes, we find that dispersal of L4 has been completely dominated by historical migrations out of Europe. We demonstrate an intimate temporal relationship between European colonial expansion into Africa and the Americas and the spread of L4 tuberculosis (TB). Markedly, in the age of antibiotics, mutations conferring antimicrobial resistance overwhelmingly emerged locally (at the level of nations), with minimal cross-border transmission of resistance. The latter finding was found to reflect the relatively recent emergence of these mutations, as a similar degree of local restriction was observed for susceptible variants emerging on comparable time scales. The restricted international transmission of drug-resistant TB suggests that containment efforts at the level of individual countries could be successful.
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Affiliation(s)
- Ola B. Brynildsrud
- Division of Infectious Diseases and Environmental Health, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
| | - Caitlin S. Pepperell
- Division of Infectious Disease, Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53726, USA
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53726, USA
| | - Philip Suffys
- Laboratory of Molecular Biology Applied to Mycobacteria, Oswaldo Cruz Institute, Avenida Brasil 4365, C.P. 926, Manguinhos 21040-360, Rio de Janeiro, Brazil
| | - Louis Grandjean
- Department of Paediatric Infectious Diseases, Imperial College London, W2 1NY, London, UK
| | - Johana Monteserin
- Instituto Nacional de Enfermedades Infecciosas, ANLIS Carlos Malbran, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires, Argentina
| | - Nadia Debech
- Division of Infectious Diseases and Environmental Health, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
| | - Jon Bohlin
- Division of Infectious Diseases and Environmental Health, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
| | - Kristian Alfsnes
- Division of Infectious Diseases and Environmental Health, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
| | - John O.-H. Pettersson
- Division of Infectious Diseases and Environmental Health, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
- Department of Medical Biochemistry and Microbiology, Zoonosis Science Center, Uppsala University, Uppsala, Sweden
- Marie Bashir Institute for Infectious Diseases and Biosecurity, Charles Perkins Centre, School of Life and Environmental Sciences and Sydney Medical School, The University of Sydney, Sydney, New South Wales 2006, Australia
- Public Health Agency of Sweden, Nobels vg 18, SE-171 82 Solna, Sweden
| | - Ingerid Kirkeleite
- Division of Infectious Diseases and Environmental Health, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
| | - Fatima Fandinho
- Laboratorio de Bacteriologia da Tuberculose, Centro de Referłncia Professor Helio Fraga-Jacarepagu, Estrada de Curicica 2000, Brazil
| | - Marcia Aparecida da Silva
- Laboratorio de Bacteriologia da Tuberculose, Centro de Referłncia Professor Helio Fraga-Jacarepagu, Estrada de Curicica 2000, Brazil
| | - Joao Perdigao
- Instituto de Investigao do Medicamento, Faculdade de Farmcia, Universidade de Lisboa, Lisboa, Portugal
| | - Isabel Portugal
- Instituto de Investigao do Medicamento, Faculdade de Farmcia, Universidade de Lisboa, Lisboa, Portugal
| | - Miguel Viveiros
- Unidade de Microbiologia Medica, Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Taane Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Maxine Caws
- Liverpool School of Tropical medicine, Department of Clinical Sciences, Liverpool, UK
- Birat-Nepal Medical Trust, Lazimpat, Kathmandu, Nepal
| | - Sarah Dunstan
- Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
| | | | - Beatriz Lopez
- Instituto Nacional de Enfermedades Infecciosas, ANLIS Carlos Malbran, Buenos Aires, Argentina
| | - Viviana Ritacco
- Instituto Nacional de Enfermedades Infecciosas, ANLIS Carlos Malbran, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires, Argentina
| | - Andrew Kitchen
- Department of Anthropology, University of Iowa, Iowa City, IA 52242, USA
| | - Tyler S. Brown
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Dick van Soolingen
- Center for Infectious Disease Research, Diagnostics and Perinatal Screening, National Institute for Public Health and the Environment, P.O. Box 1, 3720 BA Bilthoven, Netherlands
| | - Mary B. O’Neill
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53726, USA
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Kathryn E. Holt
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
- Department of Biochemistry and Molecular Biology and Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - Edward J. Feil
- Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK
| | - Barun Mathema
- Mailman School of Public Health, Columbia University, 722 West 168th Street, New York, NY 10032, USA
| | - Francois Balloux
- UCL Genetics Institute, University College London, London WC1E 6BT, UK
| | - Vegard Eldholm
- Division of Infectious Diseases and Environmental Health, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
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Wondale B, Medhin G, Abebe G, Tolosa S, Mohammed T, Teklu T, Pieper R, Ameni G. Phenotypic and genotypic drug sensitivity of Mycobacterium tuberculosis complex isolated from South Omo Zone, Southern Ethiopia. Infect Drug Resist 2018; 11:1581-1589. [PMID: 30288068 PMCID: PMC6161742 DOI: 10.2147/idr.s165088] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Background Knowledge of drug-sensitivity patterns of Mycobacterium tuberculosis complex (MTBC) strains isolated from patients is an important aspect of TB control strategy. This study was conducted to evaluate the drug sensitivity of MTBC isolates in South Omo, southern Ethiopia. Materials and methods A total of 161 MTBC isolates (153 from new cases and eight re-treatment TB cases) were isolated using Lowenstein Jensen medium of which 126 isolates were able to be tested for drug sensitivity by BACTEC™MGIT™ 960 system, while all the 161 isolates were tested by GenoType® MTBDRplus VER 2.0. Descriptive statistics and logistic regression were used to express and present results. Results On the basis of MGIT 960 system, the prevalence of mono-resistance was 9.2% (11/119) in the new cases, although neither poly-resistance nor multidrug resistance (MDR) was recorded in these cases. On the basis of GenoType MTBDRplus assay, two of the 153 isolates (1.3%) of the new cases were mono-resistant for rifampicin (RIF) and one of these isolates had known rpoB gene mutation (H526D). One of the eight (12.5%) isolates obtained from the re-treatment cases was MDR with rpoB gene mutation (D516V) and katG gene mutation (S315T2). Taking MGIT 960 system as a gold standard, the sensitivities of the MTBDRplus assay were 33.3%, 100% and 100% for detection of resistance to isoniazid, RIF and MDR, respectively. On the other hand, its specificities were 99.2%, 100% and 100% for detection of resistance to RIF, isoniazid and MDR, respectively. Conclusion The magnitude of drug resistance was relatively low in the new TB cases of South Omo as compared to the reports from the other regions of the country. This is encouraging and hence the TB Control Program in the Zone should strengthen its program so that the emergence of drug resistance is inhibited.
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Affiliation(s)
- Biniam Wondale
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia, .,Department of Biology, Arba Minch University, Arba Minch, Ethiopia,
| | - Girmay Medhin
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia,
| | - Gemeda Abebe
- Mycobacteriology Research Center, Jimma University, Jimma, Ethiopia
| | - Samuel Tolosa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia,
| | - Temesgen Mohammed
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia,
| | - Takele Teklu
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia, .,Department of Immunology and Molecular Biology, University of Gondar, Gondar, Ethiopia
| | | | - Gobena Ameni
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia,
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6
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Mortimer TD, Weber AM, Pepperell CS. Signatures of Selection at Drug Resistance Loci in Mycobacterium tuberculosis. mSystems 2018; 3:e00108-17. [PMID: 29404424 PMCID: PMC5790871 DOI: 10.1128/msystems.00108-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 01/08/2018] [Indexed: 12/21/2022] Open
Abstract
Tuberculosis (TB) is the leading cause of death by an infectious disease, and global TB control efforts are increasingly threatened by drug resistance in Mycobacterium tuberculosis. Unlike most bacteria, where lateral gene transfer is an important mechanism of resistance acquisition, resistant M. tuberculosis arises solely by de novo chromosomal mutation. Using whole-genome sequencing data from two natural populations of M. tuberculosis, we characterized the population genetics of known drug resistance loci using measures of diversity, population differentiation, and convergent evolution. We found resistant subpopulations to be less diverse than susceptible subpopulations, consistent with ongoing transmission of resistant M. tuberculosis. A subset of resistance genes ("sloppy targets") were characterized by high diversity and multiple rare variants; we posit that a large genetic target for resistance and relaxation of purifying selection contribute to high diversity at these loci. For "tight targets" of selection, the path to resistance appeared narrower, evidenced by single favored mutations that arose numerous times in the phylogeny and segregated at markedly different frequencies in resistant and susceptible subpopulations. These results suggest that diverse genetic architectures underlie drug resistance in M. tuberculosis and that combined approaches are needed to identify causal mutations. Extrapolating from patterns observed for well-characterized genes, we identified novel candidate variants involved in resistance. The approach outlined here can be extended to identify resistance variants for new drugs, to investigate the genetic architecture of resistance, and when phenotypic data are available, to find candidate genetic loci underlying other positively selected traits in clonal bacteria. IMPORTANCEMycobacterium tuberculosis, the causative agent of tuberculosis (TB), is a significant burden on global health. Antibiotic treatment imposes strong selective pressure on M. tuberculosis populations. Identifying the mutations that cause drug resistance in M. tuberculosis is important for guiding TB treatment and halting the spread of drug resistance. Whole-genome sequencing (WGS) of M. tuberculosis isolates can be used to identify novel mutations mediating drug resistance and to predict resistance patterns faster than traditional methods of drug susceptibility testing. We have used WGS from natural populations of drug-resistant M. tuberculosis to characterize effects of selection for advantageous mutations on patterns of diversity at genes involved in drug resistance. The methods developed here can be used to identify novel advantageous mutations, including new resistance loci, in M. tuberculosis and other clonal pathogens.
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Affiliation(s)
- Tatum D. Mortimer
- Division of Infectious Diseases, Department of Medicine, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Alexandra M. Weber
- Division of Infectious Diseases, Department of Medicine, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Caitlin S. Pepperell
- Division of Infectious Diseases, Department of Medicine, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, Wisconsin, USA
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7
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Spinato J, Boivin É, Bélanger-Trudelle É, Fauchon H, Tremblay C, Soualhine H. Genotypic characterization of drug resistant Mycobacterium tuberculosis in Quebec, 2002-2012. BMC Microbiol 2016; 16:164. [PMID: 27459848 PMCID: PMC4962473 DOI: 10.1186/s12866-016-0786-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 07/22/2016] [Indexed: 11/30/2022] Open
Abstract
Background The increasing emergence of drug-resistant tuberculosis presents a threat to the effective control of tuberculosis (TB). Rapid detection of drug-resistance is more important than ever to address this scourge. The purpose of this study was to genotypically characterize the first-line antitubercular drug-resistant isolates collected over 11 years in Quebec. Results The main mutations found in our resistant strains collection (n = 225) include: the S315T substitution in katG (50.2 %), the -15 C/T mutation in the inhA promoter (29 %); the S531L substitution in rpoB (43 %); the deletion 8 bp 446 / + R140S in pncA (72.9 %); the M306I (35.7 %) and M306V (21.4 %) substitutions in embB. Ten of the mutations in katG and 4 mutations identified in pncA were previously undescribed. Conclusion Screening of mutations conferring resistance to first-line antituberculous drugs using DNA-sequencing approach seems to be feasible and would drastically shorten the time to determine the resistance profile compared to the proportion method.
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Affiliation(s)
- Joanna Spinato
- McGill University, Montreal, Quebec, Canada.,Present address: Public Health Ontario Laboratory, Toronto, Ontario, M5G 1 M1, Canada
| | - Élyse Boivin
- Laboratoire de santé publique du Quebec, 20045 chemin Sainte-Marie, Sainte-Anne de Bellevue, Quebec, H9X 3R5, Canada
| | - Émilie Bélanger-Trudelle
- Laboratoire de santé publique du Quebec, 20045 chemin Sainte-Marie, Sainte-Anne de Bellevue, Quebec, H9X 3R5, Canada
| | - Huguette Fauchon
- Laboratoire de santé publique du Quebec, 20045 chemin Sainte-Marie, Sainte-Anne de Bellevue, Quebec, H9X 3R5, Canada
| | | | - Hafid Soualhine
- Laboratoire de santé publique du Quebec, 20045 chemin Sainte-Marie, Sainte-Anne de Bellevue, Quebec, H9X 3R5, Canada.
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8
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Thomas TA, Heysell SK, Houpt ER, Moore JL, Keller SJ. Outbreak of pyrazinamide-monoresistant tuberculosis identified using genotype cluster and social media analysis. Int J Tuberc Lung Dis 2015; 18:552-8. [PMID: 24903792 DOI: 10.5588/ijtld.13.0663] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING Monoresistance to pyrazinamide (PZA) has infrequently been associated with Mycobacterium tuberculosis. OBJECTIVE To report an outbreak of PZA-monoresistant M. tuberculosis in Virginia involving two genotype clusters from December 2004 to August 2010. RESULTS Thirty cases were identified involving a predominantly young, US-born population with histories of substance use and incarceration and a large proportion of children aged <15 years (n= 6, 20%); of these, 23 cases (77%) were culture-confirmed as M. tuberculosis complex. DNA fingerprinting and molecular analysis of the PZA resistance gene, pncA, demonstrated a clonal strain that was not M. bovis. Genotypic data provided the initial link between seemingly unrelated cases, and helped reveal a historic genotype cluster of cases from 2004. Further genotype cluster and contact investigation procedures, including the novel use of the social networking website Facebook.com, revealed additional links between the 2004 and 2009 genotype clusters and described an ongoing, extensive outbreak necessitating an enhanced screening and treatment protocol for contacts. CONCLUSIONS This outbreak demonstrates how tuberculosis can spread through a young, vulnerable population. The use of genotypic data and the novel incorporation of social media investigations were critical to understanding the settings and context of infectivity.
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Affiliation(s)
- T A Thomas
- University of Virginia, Charlottesville, Virginia, USA
| | - S K Heysell
- University of Virginia, Charlottesville, Virginia, USA
| | - E R Houpt
- University of Virginia, Charlottesville, Virginia, USA
| | - J L Moore
- Virginia Department of Health, Richmond, Virginia, USA
| | - S J Keller
- Virginia Department of Health, Richmond, Virginia, USA
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9
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Gene sequencing for routine verification of pyrazinamide resistance in Mycobacterium tuberculosis: a role for pncA but not rpsA. J Clin Microbiol 2012; 50:3726-8. [PMID: 22895038 DOI: 10.1128/jcm.00620-12] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pyrazinamide (PZA) is an important component of first-line therapy for the treatment of tuberculosis. Here, we evaluate targeted gene sequencing as a supplement to phenotypic PZA susceptibility testing of Mycobacterium tuberculosis. Routine sequencing of pncA, but not rpsA, is effective for verification of PZA susceptibility results.
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Benedetti A, Menzies D, Behr MA, Schwartzman K, Jin Y. How close is close enough? Exploring matching criteria in the estimation of recent transmission of tuberculosis. Am J Epidemiol 2010; 172:318-26. [PMID: 20576754 DOI: 10.1093/aje/kwq124] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
If Mycobacterium tuberculosis isolates from 2 people have the same genotype, transmission may have occurred between them. Genotyping based on the insertion sequence IS6110 uses identical restriction fragment length polymorphisms ("fingerprints") to infer transmission. However, once transmission has occurred, the genotypes may mutate, resulting in divergent fingerprints. Estimation of the proportion of tuberculosis (TB) cases due to recent transmission includes 3 approaches to determine if genotypes match: exact matching (assumes no fingerprint change); band-addition, band-loss, band-shift matching (ad hoc attempt to account for fingerprint changes); and genetic distance (directly accounts for fingerprint changes). Via simulation study, the authors varied the fingerprint change rate, level of recent transmission, and background genetic heterogeneity and estimated sensitivity, specificity, and bias of the recent transmission index by matching method. For exact matching, specificity was always high, but sensitivity decreased as the change rate increased. For band-addition, band-loss, band-shift matching, specificity decreased as genetic diversity decreased, and sensitivity remained high as the change rate increased. Genetic distance offered a compromise between the 2. Results from this study suggest that interpretation of the recent transmission index and the resulting necessary public health interventions will vary according to how researchers account for spontaneous mutation when estimating transmission from genotyping data.
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Affiliation(s)
- Andrea Benedetti
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada.
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11
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Pharmacokinetics-pharmacodynamics of pyrazinamide in a novel in vitro model of tuberculosis for sterilizing effect: a paradigm for faster assessment of new antituberculosis drugs. Antimicrob Agents Chemother 2009; 53:3197-204. [PMID: 19451303 DOI: 10.1128/aac.01681-08] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There are currently renewed efforts to develop drugs that could shorten the duration of antituberculosis therapy. This is best achieved by optimizing the sterilizing effect. However, the current pathway for the development of new molecules with the potential to have a sterilizing effect is inefficient. We designed an in vitro pharmacokinetic-pharmacodynamic model in which Mycobacterium tuberculosis replicating slowly at pH 5.8 was exposed to pyrazinamide by use of the concentration-time profiles encountered in patients. The sterilizing effect rates and the time to the emergence of drug resistance were examined. Daily pyrazinamide dosing for 28 days accurately achieved (i) the pyrazinamide pharmacokinetic parameters, (ii) the lack of early bactericidal activity, (iii) a sterilizing effect rate of 0.10 log(10) CFU/ml per day starting on day 6 of therapy, and (iv) a time to the emergence of resistance of the from 2 to 3 weeks of monotherapy encountered in patients with tuberculosis. Next, dose-scheduling studies were performed. The sterilizing effect was linked to the pyrazinamide ratio of the area under the concentration-time curve from 0 to 24 h (AUC(0-24)) to the MIC (r(2) = 0.80 to 0.90), with 90% of the maximal effect being achieved by an AUC(0-24)/MIC of 209.08. Resistance suppression was associated with the percentage of time that the concentration persisted above the MIC (r(2) = 0.73 to 0.91). Monte Carlo simulations of 10,000 patients demonstrated that the currently recommended pyrazinamide doses (15 to 30 mg/kg of body weight/day) achieved the AUC(0-24)/MIC of 209.08 in the epithelial lining fluid of only 15.1 to 53.3% of patients. Doses of >60 mg/kg per day performed better. Our vitro model for the sterilizing effect, together with Monte Carlo simulations, can be used for the faster identification of the clinical doses that are needed to achieve a sterilizing effect and that can then be studied in clinical trials.
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12
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Brassard P, Henry KA, Schwartzman K, Jomphe M, Olson SH. Geography and genealogy of the human host harbouring a distinctive drug-resistant strain of tuberculosis. INFECTION GENETICS AND EVOLUTION 2007; 8:247-57. [PMID: 18316250 DOI: 10.1016/j.meegid.2007.11.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Revised: 11/28/2007] [Accepted: 11/29/2007] [Indexed: 10/22/2022]
Abstract
For a strain of Mycobacterium tuberculosis mono-resistant to pyrazinamide (PZA), we report the geographic distribution within Quebec of the 77 cases diagnosed during 1990-2000. Known as the Quebec mutation (or the pncA deletion), the strain is rare in urban areas and showed an unexpected concentration in Mauricie, one of the 16 health districts of the province, with a cluster of 10 cases situated in a rural area of 35-km radius. The cases occurred among people >50 (98%), of French Canadian origins (90%), and are understood to have arisen by reactivation. The rarity in Montreal and smaller cities is explained by the youthfulness of massive postwar migrations. To reach back into the history of settlement, we examined genealogies: 92,429 ancestral marriages for 32 of the 77 PZA-resistant isolates and 226,535 for a set of 85 controls with isolates of more diverse mycobacterial strains. Genealogical analysis showed no salient common ancestor for the cases, and kinship among them was no greater than observed in control samples from the same regions. But it identified an unsuspected geographical region as the site of ancestral concentrations prior to 1840, for both resistant strains and controls. The following scenario is proposed for the resistant strain: endemic in a specific geographical region by 1800, it dispersed with families moving into regions opened to settlement in the 1840s and 1850s, among them Mauricie, where dispersion was intensified by seasonal mobility of labour in logging, milling and marketing timber. In high-incidence areas, it is difficult to distinguish cases of reactivation from recent infections, but the low-incidence context allows us to observe a 200-year trajectory of a distinctive drug-resistant strain of M. tuberculosis.
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Affiliation(s)
- Paul Brassard
- Department of Medicine, McGill University Health Center, Royal Victoria Hospital, Montréal, Québec, Canada H3A 1A1.
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13
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Yeo IKT, Tannenbaum T, Scott AN, Kozak R, Behr MA, Thibert L, Schwartzman K. Contact investigation and genotyping to identify tuberculosis transmission to children. Pediatr Infect Dis J 2006; 25:1037-43. [PMID: 17072127 DOI: 10.1097/01.inf.0000241101.12510.3c] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Tuberculosis (TB) in young children is an indicator of ongoing community transmission. We examined contact investigations related to pediatric TB, yield for source case identifications and genotypes for relevant Mycobacterium tuberculosis isolates in a low-incidence setting. METHODS We reviewed public health data for all patients with TB aged <18 years reported to Montreal authorities during 1996 to 2000. M. tuberculosis isolates from patients of all ages were subjected to IS6110-based genotyping, supplemented by spoligotyping, to compare isolates from children and adults during the same years. RESULTS Sixty-six patients aged <18 years were diagnosed with active TB from 1996 to 2000. Mean age was 11.1 years (standard deviation 6.7 years). Twenty-five children (38%) were Canadian-born, all with at least one foreign-born parent. Nineteen children were diagnosed after contact investigations of known adult cases; 8 underwent no contact investigation. For the remaining 39 children, a total of 616 contacts were identified. The median number of contacts per child was 9 (interquartile range, 6-10). Four hundred eighty-one contacts (78%) underwent tuberculin testing; 188 (39%) were reactors and 186 (39%) began treatment of latent TB. Investigations uncovered 4 probable source cases, all involving parents or other relatives. M. tuberculosis genotyping for 38 children identified up to 14 additional possible source cases; in only one was a possible epidemiologic link evident from public health records. CONCLUSIONS Among largely foreign-born children with active TB, contact investigations were extensive and often identified latent tuberculosis infection--but rarely source cases. However, genotyping suggested substantial, previously unrecognized transmission to children despite low overall incidence.
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Affiliation(s)
- Ivan K T Yeo
- Respiratory Epidemiology Unit, McGill University, Montreal, Quebec, Canada
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14
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Streicher EM, Victor TC, van der Spuy G, Sola C, Rastogi N, van Helden PD, Warren RM. Spoligotype signatures in the Mycobacterium tuberculosis complex. J Clin Microbiol 2006; 45:237-40. [PMID: 17065260 PMCID: PMC1828946 DOI: 10.1128/jcm.01429-06] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Evolution of the direct repeat region in Mycobacterium tuberculosis has created unique spoligotype signatures specifically associated with IS6110-defined strain families. Spoligotyping signatures may enable the analysis of the strain population structure in different settings and will enable the rapid identification of strain families that acquire drug resistance or escape protective immunity in drug and vaccine trials.
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Affiliation(s)
- E M Streicher
- DST/NRF Centre of Excellence in Biomedical TB Research, Department of Medical Biochemistry, Stellenbosch University, Tygerberg, South Africa 7505
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Scott AN, Menzies D, Tannenbaum TN, Thibert L, Kozak R, Joseph L, Schwartzman K, Behr MA. Sensitivities and specificities of spoligotyping and mycobacterial interspersed repetitive unit-variable-number tandem repeat typing methods for studying molecular epidemiology of tuberculosis. J Clin Microbiol 2005; 43:89-94. [PMID: 15634955 PMCID: PMC540143 DOI: 10.1128/jcm.43.1.89-94.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The development of PCR-based genotyping modalities (spoligotyping and mycobacterial interspersed repetitive unit-variable-number tandem repeat [MIRU-VNTR] typing) offers promise for real-time molecular epidemiological studies of tuberculosis (TB). However, the utility of these methods depends on their capacity to appropriately classify isolates. To determine the operating parameters of spoligotyping and MIRU-VNTR typing, we have compared results generated by these newer tests to the standard typing method, IS6110 restriction fragment length polymorphism, in analyses restricted to high-copy-number IS6110 isolates. Sensitivities of the newer tests were estimated as the percentages of isolates with identical IS6110 fingerprints that had identical spoligotypes and MIRU-VNTR types. The specificities of these tests were estimated as the percentages of isolates with unique IS6110 fingerprints that had unique spoligotypes and MIRU-VNTR types. The sensitivity of MIRU-VNTR typing was 52% (95% confidence interval [CI], 31 to 72%), and the sensitivity of spoligotyping was 83% (95% CI, 63 to 95%). The specificity of MIRU-VNTR typing was 56% (95% CI, 51 to 62%), and the specificity of spoligotyping was 40% (95% CI, 35 to 46%). The proportion of isolates estimated to be due to recent transmission was 4% by identical IS6110 patterns, 19% by near-identical IS6110 patterns, 33% by MIRU-VNTR typing, and 53% by spoligotyping. The low calculated specificities of spoligotyping and MIRU-VNTR typing led to misclassification of cases, inflated estimates of TB transmission, and low positive predictive values, suggesting that these techniques have unsuitable operating parameters for population-based molecular epidemiology studies.
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Affiliation(s)
- Allison N Scott
- Department of Epidemiology and Biostatistics, McGill University, Montreal, Quebec, Canada
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16
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Nguyen D, Brassard P, Menzies D, Thibert L, Warren R, Mostowy S, Behr M. Genomic characterization of an endemic Mycobacterium tuberculosis strain: evolutionary and epidemiologic implications. J Clin Microbiol 2004; 42:2573-80. [PMID: 15184436 PMCID: PMC427889 DOI: 10.1128/jcm.42.6.2573-2580.2004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In a study of 302 Mycobacterium tuberculosis clinical isolates from the low-incidence Canadian-born population of Quebec, we characterized a large endemic strain family by using genomic deletions. The DS6(Quebec) deleted region (11.4 kb) defined a strain family of 143 isolates encompassing two subgroups: one characterized by pyrazinamide (PZA) susceptibility and the other marked by a PZA-monoresistant phenotype. A second deletion (8 bp) in the pncA gene was shared by all 76 isolates with the PZA resistance phenotype, whereas a third DRv0961 deletion (970 bp) defined a further subset of 15 isolates. From their deletion profiles, we derived a most parsimonious evolutionary scenario and compared multiple standard genotyping modalities (using IS6110 restriction fragment length polymorphism [RFLP], spoligotyping, and mycobacterial interspersed repetitive units [MIRU]) across the deletion-based subgroups. The use of a single genotyping modality yielded an unexpectedly high proportion of clustered isolates for a high IS6110 copy strain (27% by IS6110 RFLP, 61% by MIRU, and 77% by spoligotyping). By combining all three modalities, only 14% were genotypically clustered overall, a result more congruent with the epidemiologic profile of reactivation tuberculosis, as suggested by the older age (mean age, 60 years), rural setting, and low proportion of epidemiologic links. These results provide insight into the evolution of genotypes in endemic strains and the potential for false clustering in molecular epidemiologic studies.
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Affiliation(s)
- Dao Nguyen
- Division of Infectious Diseases and Medical Microbiology, McGil University Health Centre, Montreal, Quebec, Canada
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Koivula T, Ekman M, Leitner T, Löfdahl S, Ghebremicahel S, Mostowy S, Behr MA, Svenson SB, Källenius G. Genetic characterization of the Guinea-Bissau family of Mycobacterium tuberculosis complex strains. Microbes Infect 2004; 6:272-8. [PMID: 15026014 DOI: 10.1016/j.micinf.2003.12.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2003] [Accepted: 12/09/2003] [Indexed: 10/26/2022]
Abstract
In a previous study of Mycobacterium tuberculosis complex isolates from Guinea-Bissau in West Africa, we identified a unique group of strains, designated here as the Guinea-Bissau family of strains, which, although genotypically closely related, phenotypically demonstrated a considerable heterogeneity. We conducted here a detailed genotypic analysis of a subset (n = 35) of these isolates. Based on the data obtained, and by comparison of known corresponding genes in mycobacteria outside the M. tuberculosis complex, we propose that the Guinea-Bissau strains belong to a unique branch of the M. tuberculosis complex tree in between classical M. tuberculosis and classical M. bovis. These observations are discussed in their significance in M. tuberculosis complex classification.
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Affiliation(s)
- Tuija Koivula
- Swedish Institute for Infectious Disease Control, 17182 Solna, Sweden
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Nguyen D, Proulx JF, Westley J, Thibert L, Dery S, Behr MA. Tuberculosis in the Inuit Community of Quebec, Canada. Am J Respir Crit Care Med 2003; 168:1353-7. [PMID: 14500266 DOI: 10.1164/rccm.200307-910oc] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In low-incidence countries targeting tuberculosis (TB) elimination, TB remains a problem of a few high-risk groups. In Canada, Aboriginals, and particularly the Arctic Inuit communities, have witnessed dramatic decreases in TB during the 1960s to 1970s, but rates remain at least 10 to 20 times higher than the national average. We are describing the results of an integrated traditional and molecular epidemiology study of all culture-positive Mycobacterium tuberculosis cases in the Arctic Inuit communities of Quebec from 1990 until 2000. The demographic characteristics of the 46 TB cases included in the study were most notable for a bimodal age distribution (48% under 25 years). Genotyping analysis using multiple modalities (IS6110 restriction fragment length polymorphism, spoligotype, mycobacterial interspersed repetitive units-variable number tandem repeats) showed that 76% (35/46) of TB cases were clustered (six clusters, median size four cases) and estimated that at least 62.5% of TB cases were due to ongoing transmission. By integrating the epidemiologic and genotyping data, we observed that the genotyping clustering results were concordant with recognized epidemiologic links but most notably identified previously unrecognized intervillage transmission. This study demonstrates significant ongoing transmission in a geographically isolated, low-density population. In a resource-rich country such as Canada, these communities illustrate some of the persistent challenges of TB control and elimination.
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Affiliation(s)
- Dao Nguyen
- Department of Medicine and Research Institute, McGill University Health Centre, Montreal, Quebec, Canada
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