Molecular epidemiology of Mycobacterium tuberculosis among South African gold miners

Barun Mathema, James J. Lewis, Jeremy Connors, Violet N. Chihota, Elena Shashkina, Minty Van Der Meulen, Edward A. Graviss, Ngan P. Ha, Barry N. Kreiswirth, Alison D. Grant, Katherine L. Fielding, Susan E. Dorman, Gavin J. Churchyard

Research output: Contribution to journalArticle

12 Scopus citations

Abstract

Rationale: HIV-associated tuberculosis remains a major health problem among the gold-mining workforce in South Africa. We postulate that high levels of recent transmission, indicated by strain clustering, are fueling the tuberculosis epidemic among gold miners. Objectives: To combine molecular and epidemiologic data to describe Mycobacterium tuberculosis genetic diversity, estimate levels of transmission, and examine risk factors for clustering. Methods: We conducted a cross-sectional study of culturepositive M. tuberculosis isolates in 15 gold mine shafts across three provinces in South Africa. All isolates were subject IS6110-based restriction fragment length polymorphisms, and we performed spoligotyping analysis and combined it with basic demographic and clinical information. Measurements and Main Results: Of the 1,602 M. tuberculosis patient isolates, 1,240 (78%) had genotyping data available for analysis. A highly diverse bacillary population was identified, comprising a total of 730 discrete genotypes. Four genotypic families (Latin American Mediterranean spoligotype family; W-Beijing; AH or X; and T1-T4) accounted for over 50% of all strains. Overall, 45% (560/1,240) of strains were genotypically clustered. The minimum estimate for recent transmission (n - 1 method) was 32% (range, 27-34%). There were no individual-level risk factors for clustering, apart from borderline evidence for being non-South African and having self-reported HIV infection. Conclusions: The high M. tuberculosis genetic diversity and lack of risk factors for clustering are indicative of a universal risk for disease among gold miners and likely mixing with nonmining populations. Our results underscore the urgent need to intensify interventions to interrupt transmission across the entire gold-mining workforce in South Africa.

Original languageEnglish (US)
Pages (from-to)12-20
Number of pages9
JournalAnnals of the American Thoracic Society
Volume12
Issue number1
DOIs
StatePublished - Jan 1 2015

Keywords

  • Gold mines
  • Molecular epidemiology
  • South africa
  • Tuberculosis

ASJC Scopus subject areas

  • Pulmonary and Respiratory Medicine

Fingerprint Dive into the research topics of 'Molecular epidemiology of Mycobacterium tuberculosis among South African gold miners'. Together they form a unique fingerprint.

Cite this