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Hussien B, Zewude A, Wondale B, Hailu A, Ameni G. Spoligotyping of Clinical Isolates of Mycobacterium tuberculosis Complex Species in the Oromia Region of Ethiopia. Front Public Health 2022; 10:808626. [PMID: 35372211 PMCID: PMC8970530 DOI: 10.3389/fpubh.2022.808626] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 02/03/2022] [Indexed: 11/22/2022] Open
Abstract
Background Tuberculosis (TB) is a leading cause of morbidity and mortality in Ethiopia. Investigation of the Mycobacterium tuberculosis complex (MTBC) species circulating in the Ethiopian population would contribute to the efforts made to control TB in the country. Therefore, this study was conducted to investigate the MTBC species and spoligo patterns in the Oromia region (central) of Ethiopia. Methods A cross-sectional study design was used to recruit 450 smear positive pulmonary TB (PTB) cases from the Oromia region between September 2017 and August 2018. Mycobacteria were isolated from sputum samples on the Lowenstein Jensen (LJ) medium. Molecular identification of the isolates was performed by spoligotyping. The results of spoligotyping were transferred into a query box in the SITVIT2 database and Run TB-Lineage in the TB Insight website for the identification of spoligo international type (SIT) number and linages of the isolates, respectively. Statistical Product and Service Solutions (SPSS) 20 was applied for statistical analysis. Results Three hundred and fifteen isolates were grouped under 181 different spoligotype patterns. The most dominantly isolated spoligotype pattern was SIT149 and it consisted of 23 isolates. The majority of the isolates were grouped under Euro-American (EA), East-African-Indian (EAI), and Indo-Oceanic (IO) lineages. These lineages consisted of 79.4, 9.8, and 9.8% of the isolates, respectively. One hundred and sixty-five of the isolates were classified under 31 clustered spoligotypes whereas the remaining 150 were singleton types. Furthermore, 91.1% of the total isolates were classified as orphan types. Clustering of spoligotypes was associated (p < 0.001) with EAI lineage. Conclusion SIT149 and EA lineage were predominantly isolated from the Oromia region substantiating the findings of the similar studies conducted in other regions of Ethiopia. The observation of significant number of singleton and orphan spoligotypes warrants for additional genetic typing of the isolates using method(s) with a better discriminatory power than spoligotyping.
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Affiliation(s)
- Bedru Hussien
- Department of Public Health, Goba Referral Hospital, Madda Walabu University, Goba, Ethiopia
| | - Aboma Zewude
- Malaria and Neglected Tropical Diseases Research Team, Ethiopian Public Health Institute, Ministry of Health, Addis Ababa, Ethiopia
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Biniam Wondale
- Department of Biology, Arba Minch University, Arba Minch, Ethiopia
| | - Awraris Hailu
- Department of Public Health, College of Health Sciences, Debre Birhan University, Debre Birhan, Ethiopia
| | - Gobena Ameni
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
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Exploring genotype concordance in epidemiologically linked cases of tuberculosis in New York City. Epidemiol Infect 2016; 145:503-514. [PMID: 27866489 DOI: 10.1017/s0950268816002399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Comparing genotype results of tuberculosis (TB) isolates from individuals diagnosed with TB can support or refute transmission; however, these conclusions are based upon the criteria used to define a genotype match. We used a genotype-match definition which allowed for variation in IS6110 restriction fragment length polymorphism (RFLP) to support transmission between epidemiologically linked persons. Contacts of individuals with infectious TB (index cases) diagnosed in New York City from 1997 to 2003 who subsequently developed TB (contact cases) from 1997 to 2007 were identified. For each contact case and index case (case-pair), isolate genotypes (spoligotype and RFLP results) were evaluated. Isolates from case-pairs were classified as exact or non-exact genotype match. Genotypes from non-exact match case-pairs were reviewed at the genotyping laboratory to determine if the isolates met the near-genotype-match criteria (exactly matching spoligotype and similar RFLP banding patterns). Of 118 case-pairs identified, isolates from 83 (70%) had exactly matching genotypes and 14 (12%) had nearly matching genotypes (supporting transmission), while the remaining 21 (18%) case-pairs had discordant genotypes (refuting transmission). Using identical genotype-match criteria for isolates from case-pairs epidemiologically linked through contact investigation may lead to underestimation of transmission. TB programmes should consider the value of expanding genotype-match criteria to more accurately assess transmission between such cases.
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Kasaie P, Mathema B, Kelton WD, Azman AS, Pennington J, Dowdy DW. A Novel Tool Improves Existing Estimates of Recent Tuberculosis Transmission in Settings of Sparse Data Collection. PLoS One 2015; 10:e0144137. [PMID: 26679499 PMCID: PMC4683006 DOI: 10.1371/journal.pone.0144137] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 11/14/2015] [Indexed: 11/19/2022] Open
Abstract
In any setting, a proportion of incident active tuberculosis (TB) reflects recent transmission (“recent transmission proportion”), whereas the remainder represents reactivation. Appropriately estimating the recent transmission proportion has important implications for local TB control, but existing approaches have known biases, especially where data are incomplete. We constructed a stochastic individual-based model of a TB epidemic and designed a set of simulations (derivation set) to develop two regression-based tools for estimating the recent transmission proportion from five inputs: underlying TB incidence, sampling coverage, study duration, clustered proportion of observed cases, and proportion of observed clusters in the sample. We tested these tools on a set of unrelated simulations (validation set), and compared their performance against that of the traditional ‘n-1’ approach. In the validation set, the regression tools reduced the absolute estimation bias (difference between estimated and true recent transmission proportion) in the ‘n-1’ technique by a median [interquartile range] of 60% [9%, 82%] and 69% [30%, 87%]. The bias in the ‘n-1’ model was highly sensitive to underlying levels of study coverage and duration, and substantially underestimated the recent transmission proportion in settings of incomplete data coverage. By contrast, the regression models’ performance was more consistent across different epidemiological settings and study characteristics. We provide one of these regression models as a user-friendly, web-based tool. Novel tools can improve our ability to estimate the recent TB transmission proportion from data that are observable (or estimable) by public health practitioners with limited available molecular data.
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Affiliation(s)
- Parastu Kasaie
- Department of Epidemiology, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, MD, United States of America
| | - Barun Mathema
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY, United States of America
| | - W. David Kelton
- Department of Operations, Business Analytics, and Information Systems, University of Cincinnati, Cincinnati, OH, United States of America
| | - Andrew S. Azman
- Department of Epidemiology, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, MD, United States of America
| | - Jeff Pennington
- Department of Epidemiology, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, MD, United States of America
| | - David W. Dowdy
- Department of Epidemiology, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, MD, United States of America
- * E-mail:
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Sun Z, Li W, Xu S, Huang H. The discovery, function and development of the variable number tandem repeats in different Mycobacterium species. Crit Rev Microbiol 2015; 42:738-58. [PMID: 26089025 DOI: 10.3109/1040841x.2015.1022506] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The method of genotyping by variable number tandem repeats (VNTRs) facilitates the epidemiological studies of different Mycobacterium species worldwide. Until now, the VNTR method is not fully understood, for example, its discovery, function and classification. The inconsistent nomenclature and terminology of VNTR is especially confusing. In this review, we first describe in detail the VNTRs in Mycobacterium tuberculosis (M. tuberculosis), as this pathogen resulted in more deaths than any other microbial pathogen as well as for which extensive studies of VNTRs were carried out, and then we outline the recent progress of the VNTR-related epidemiological research in several other Mycobacterium species, such as M. abscessus, M. africanum, M. avium, M. bovis, M. canettii, M. caprae, M. intracellulare, M. leprae, M. marinum, M. microti, M. pinnipedii and M. ulcerans from different countries and regions. This article is aimed mainly at the practical notes of VNTR to help the scientists in better understanding and performing this method.
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Affiliation(s)
- Zhaogang Sun
- a Beijing Tuberculosis & Thoracic Tumor Research Institute, Beijing Key Laboratory for Drug Resistance Tuberculosis Research , Beijing , China and
| | - Weimin Li
- b Beijing Chest Hospital, National Tuberculosis Clinical Laboratory, Capital Medical University , Beijing , China
| | - Shaofa Xu
- b Beijing Chest Hospital, National Tuberculosis Clinical Laboratory, Capital Medical University , Beijing , China
| | - Hairong Huang
- b Beijing Chest Hospital, National Tuberculosis Clinical Laboratory, Capital Medical University , Beijing , China
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Mehaffy C, Guthrie JL, Alexander DC, Stuart R, Rea E, Jamieson FB. Marked microevolution of a unique Mycobacterium tuberculosis strain in 17 years of ongoing transmission in a high risk population. PLoS One 2014; 9:e112928. [PMID: 25405861 PMCID: PMC4236100 DOI: 10.1371/journal.pone.0112928] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 08/22/2014] [Indexed: 11/18/2022] Open
Abstract
The transmission and persistence of Mycobacterium tuberculosis within high risk populations is a threat to tuberculosis (TB) control. In the current study, we used whole genome sequencing (WGS) to decipher the transmission dynamics and microevolution of M. tuberculosis ON-A, an endemic strain responsible for an ongoing outbreak of TB in an urban homeless/under-housed population. Sixty-one M. tuberculosis isolates representing 57 TB cases from 1997 to 2013 were subjected to WGS. Sequencing data was integrated with available epidemiological information and analyzed to determine how the M. tuberculosis ON-A strain has evolved during almost two decades of active transmission. WGS offers higher discriminatory power than traditional genotyping techniques, dividing the M. tuberculosis ON-A strain into 6 sub-clusters, each defined by unique single nucleotide polymorphism profiles. One sub-cluster, designated ON-ANM (Natural Mutant; 26 isolates from 24 cases) was also defined by a large, 15 kb genomic deletion. WGS analysis reveals the existence of multiple transmission chains within the same population/setting. Our results help validate the utility of WGS as a powerful tool for identifying genomic changes and adaptation of M. tuberculosis.
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Affiliation(s)
- Carolina Mehaffy
- Public Health Ontario, Toronto, Canada
- University of Toronto, Toronto, Canada
- * E-mail:
| | | | | | | | | | - Frances B. Jamieson
- Public Health Ontario, Toronto, Canada
- University of Toronto, Toronto, Canada
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Oren E, Narita M, Nolan C, Mayer J. Neighborhood socioeconomic position and tuberculosis transmission: a retrospective cohort study. BMC Infect Dis 2014; 14:227. [PMID: 24767197 PMCID: PMC4013806 DOI: 10.1186/1471-2334-14-227] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 04/16/2014] [Indexed: 11/29/2022] Open
Abstract
Background Current understanding of tuberculosis (TB) genotype clustering in the US is based on individual risk factors. This study sought to identify whether area-based socioeconomic status (SES) was associated with genotypic clustering among culture-confirmed TB cases. Methods A retrospective cohort analysis was performed on data collected on persons with incident TB in King County, Washington, 2004–2008. Multilevel models were used to identify the relationship between area-level SES at the block group level and clustering utilizing a socioeconomic position index (SEP). Results Of 519 patients with a known genotyping result and block group, 212 (41%) of isolates clustered genotypically. Analyses suggested an association between lower area-based SES and increased recent TB transmission, particularly among US-born populations. Models in which community characteristics were measured at the block group level demonstrated that lower area-based SEP was positively associated with genotypic clustering after controlling for individual covariates. However, the trend in higher clustering odds with lower SEP index quartile diminished when additional block-group covariates. Conclusions Results stress the need for TB control interventions that take area-based measures into account, with particular focus on poor neighborhoods. Interventions based on area-based characteristics, such as improving case finding strategies, utilizing location-based screening and addressing social inequalities, could reduce recent rates of transmission.
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Affiliation(s)
- Eyal Oren
- Division of Epidemiology & Biostatistics, University of Arizona, Tucson, AZ, USA.
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Gomes T, Vinhas SA, Reis-Santos B, Palaci M, Peres RL, Aguiar PP, Ribeiro FKC, Marques HS, Dettoni VDV, Johnson JL, Riley LW, Maciel EL. Extrapulmonary tuberculosis: Mycobacterium tuberculosis strains and host risk factors in a large urban setting in Brazil. PLoS One 2013; 8:e74517. [PMID: 24098337 PMCID: PMC3788772 DOI: 10.1371/journal.pone.0074517] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 08/02/2013] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Factors related to the development of extrapulmonary forms of tuberculosis (EPTB) are still poorly understood, particularly in high-endemic countries like Brazil. The objective of the paper is to determine host and Mycobacterium tuberculosis (MTB) strain-related factors associated with the development of EPTB in Espírito Santo state, Brazil. METHODS AND FINDINGS We conducted a retrospective laboratory-based surveillance study of new tuberculosis (TB) cases diagnosed in Espírito Santo state, Brazil between 1998 and 2007. We genotyped 612 isolates of MTB from 606 TB patients using spoligotyping and IS6110-restriction fragment length polymorphism (RFLP) typing and compared sociodemographic and clinical characteristics of patients with pulmonary TB (PTB) and EPTB. Among 606 patients, 464 (77%) had PTB, 79 (13%) had EPTB, 51 (8%) had both, and 12 (2%) had miliary TB. The IS6110 RFLP analysis demonstrated that 250 (41%) isolates belonged to clustered RFLP patterns, 27 (11%) of which were from EPTB. We identified 73 clusters including 35 (48%) composed of 2 isolates each. By spoligotyping, 506 (83%) MTB isolates fell into known patterns and 106 (17%) fell into patterns with no family assignment; 297 (48%) isolates belonged to the Latin-American Mediterranean family. Higher school level (4-7 years OR: 0.16 95% CI 0.34-0.73 and > 8 years of education, OR 0.06 95% CI 0.009-0.50) white ethnicity (OR: 2.54 95% CI 1.03-6.25) and HIV infection (OR: 16.83 95% CI 5.23-54.18) were associated with EPTB. No specific strain lineage or percentage of clustering was associated with EPTB. CONCLUSIONS These results demonstrate that risk factors for EPTB are related more to host than to MTB strain lineage characteristics.
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Affiliation(s)
- Teresa Gomes
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
| | - Solange Alves Vinhas
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
| | - Bárbara Reis-Santos
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
| | - Moisés Palaci
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
| | - Renata Lyrio Peres
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
| | - Paola P. Aguiar
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
| | | | - Hebert Silva Marques
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
| | | | - John L. Johnson
- Tuberculosis Research Unit, Department of Medicine, Division of Infectious Diseases, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Lee W. Riley
- Division of Infectious Disease and Vaccinology, School of Public Health, University of California, Berkeley, California, United States of America
| | - Ethel Leonor Maciel
- Graduate Program in Infectious Diseases, Federal University of Espírito Santo, Vitória, Brazil
- Graduate Program in Public Health, Federal University of Espírito Santo, Vitória, Brazil
- * E-mail:
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Fox GJ, Nhung NV, Sy DN, Lien LT, Cuong NK, Britton WJ, Marks GB. Contact investigation in households of patients with tuberculosis in Hanoi, Vietnam: a prospective cohort study. PLoS One 2012; 7:e49880. [PMID: 23166785 PMCID: PMC3499505 DOI: 10.1371/journal.pone.0049880] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 10/15/2012] [Indexed: 11/29/2022] Open
Abstract
Setting Existing tuberculosis control strategies in Vietnam are based on symptomatic patients attending health services for investigation. This approach has not resulted in substantial reductions in the prevalence of tuberculosis disease, despite the National Tuberculosis Program achieving high treatment completion rates. Alternative approaches are being considered. Objective To determine the feasibility and yield of contact investigation in households of patients with smear positive pulmonary tuberculosis among household members of tuberculosis patients in Hanoi, Vietnam. Methods Household contacts of patients with smear positive pulmonary tuberculosis were recruited at four urban and rural District Tuberculosis Units in Hanoi. Clinical and radiological screening was conducted at baseline, six months and 12 months. Sputum microscopy and culture was performed in contacts suspected of having tuberculosis. MIRU-VNTR molecular testing was used to compare the strains of patients and their contacts with disease. Results Among 545 household contacts of 212 patients, four were diagnosed with tuberculosis at baseline (prevalence 734 cases per 100,000 persons, 95% CI 17–1451) and one was diagnosed with tuberculosis during the subsequent 12 months after initial screening (incidence 180 cases per 100,000 person-years, 95% CI 44–131). Two of these cases were culture positive for M. tuberculosis and both had identical or near-identical MIRU-VNTR strain types. Conclusion Household contacts of patients with potentially infectious forms of tuberculosis have a high prevalence of disease. Household contact investigation is feasible in Vietnam. Further research is required to investigate its effectiveness.
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Affiliation(s)
- Gregory James Fox
- Woolcock Institute of Medical Research, Sydney, New South Wales, Australia.
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Walter ND, Strong M, Belknap R, Ordway DJ, Daley CL, Chan ED. Translating basic science insight into public health action for multidrug- and extensively drug-resistant tuberculosis. Respirology 2012; 17:772-91. [PMID: 22458269 PMCID: PMC4540333 DOI: 10.1111/j.1440-1843.2012.02176.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Multidrug (MDR)- and extensively drug-resistant (XDR) tuberculosis (TB) impose a heavy toll of human suffering and social costs. Controlling drug-resistant TB is a complex global public health challenge. Basic science advances including elucidation of the genetic basis of resistance have enabled development of new assays that are transforming the diagnosis of MDR-TB. Molecular epidemiological approaches have provided new insights into the natural history of TB with important implications for drug resistance. In the future, progress in understanding Mycobacterium tuberculosis strain-specific human immune responses, integration of systems biology approaches with traditional epidemiology and insight into the biology of mycobacterial persistence have potential to be translated into new tools for diagnosis and treatment of MDR- and XDR-TB. We review recent basic sciences developments that have contributed or may contribute to improved public health response.
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Affiliation(s)
- Nicholas D Walter
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Denver, Aurora, Colorado, USA.
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Garzelli C, Rindi L. Molecular epidemiological approaches to study the epidemiology of tuberculosis in low-incidence settings receiving immigrants. INFECTION GENETICS AND EVOLUTION 2012; 12:610-8. [DOI: 10.1016/j.meegid.2011.10.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 10/17/2011] [Accepted: 10/18/2011] [Indexed: 10/15/2022]
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van Schalkwyk C, Cule M, Welte A, van Helden P, van der Spuy G, Uys P. Towards eliminating bias in cluster analysis of TB genotyped data. PLoS One 2012; 7:e34109. [PMID: 22479534 PMCID: PMC3315507 DOI: 10.1371/journal.pone.0034109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 02/23/2012] [Indexed: 11/18/2022] Open
Abstract
The relative contributions of transmission and reactivation of latent infection to TB cases observed clinically has been reported in many situations, but always with some uncertainty. Genotyped data from TB organisms obtained from patients have been used as the basis for heuristic distinctions between circulating (clustered strains) and reactivated infections (unclustered strains). Naïve methods previously applied to the analysis of such data are known to provide biased estimates of the proportion of unclustered cases. The hypergeometric distribution, which generates probabilities of observing clusters of a given size as realized clusters of all possible sizes, is analyzed in this paper to yield a formal estimator for genotype cluster sizes. Subtle aspects of numerical stability, bias, and variance are explored. This formal estimator is seen to be stable with respect to the epidemiologically interesting properties of the cluster size distribution (the number of clusters and the number of singletons) though it does not yield satisfactory estimates of the number of clusters of larger sizes. The problem that even complete coverage of genotyping, in a practical sampling frame, will only provide a partial view of the actual transmission network remains to be explored.
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Affiliation(s)
- Cari van Schalkwyk
- The South African Department of Science and Technology/National Research Foundation (DST/NRF) Centre of Excellence in Epidemiological Modelling and Analysis, Faculty of Science, University of Stellenbosch, Stellenbosch, South Africa.
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El Khéchine A, Drancourt M. Diagnosis of pulmonary tuberculosis in a microbiological laboratory. Med Mal Infect 2011; 41:509-17. [DOI: 10.1016/j.medmal.2011.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 04/08/2011] [Accepted: 07/22/2011] [Indexed: 02/05/2023]
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