title: Human immunodeficiency virus and the prevalence of undiagnosed tuberculosis in African gold miners.
abstract: We hypothesized that rapid presentation may be a general feature of tuberculosis (TB) associated with human immunodeficiency virus (HIV) that limits the impact of HIV on the point prevalence of TB. To investigate this, we performed a cross-sectional HIV and TB disease survey with retrospective and prospective follow-up. HIV prevalence among 1,773 systematically recruited miners was 27%. TB incidence was much more strongly HIV associated (incidence rate ratio, 5.5; 95% confidence interval [CI], 3.5-8.6) than the point prevalence of undiagnosed TB disease (odds ratio, 1.7; 95% CI, 0.9-3.3). For smear-positive TB, 7 of 9 (78%) prevalent cases were HIV negative, and point prevalence was nonsignificantly lower in miners who were HIV positive (odds ratio, 0.8; 95% CI, 0.1-4.2). The calculated mean duration of smear positivity before diagnosis (point prevalence/incidence) was substantially shorter for HIV-positive than HIV-negative TB patients (0.17 and 1.15 years, respectively; ratio, 0.15; 95% CI, 0.00-0.73). HIV has considerably less impact on the point prevalence of TB disease than on TB incidence, probably because rapid disease progression increases presentation and case-finding rates. The difference in mean duration of smear positivity was particularly marked and, if generalizable, will have major implications for TB control prospects in high HIV prevalence areas.
authors.affiliation: Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom. elc1@mweb.co.zw
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Corbett
authors.forename: Salome
authors.initials: S
authors.lastname: Charalambous
authors.forename: Vicky M
authors.initials: VM
authors.lastname: Moloi
authors.forename: Katherine
authors.initials: K
authors.lastname: Fielding
authors.forename: Alison D
authors.initials: AD
authors.lastname: Grant
authors.forename: Christopher
authors.initials: C
authors.lastname: Dye
authors.forename: Kevin M
authors.initials: KM
authors.lastname: De Cock
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Hayes
authors.forename: Brian G
authors.initials: BG
authors.lastname: Williams
authors.forename: Gavin J
authors.initials: GJ
authors.lastname: Churchyard
mesh_terms: D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D006046:Gold; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008906:Mining / Q000706:statistics & numerical data*; D015995:Prevalence; D012189:Retrospective Studies; D013019:South Africa / Q000453:epidemiology; D013997:Time Factors; D014376:Tuberculosis / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology*
chemical_list: D006046:Gold