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 casefinding 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.

Antiretroviral therapy for tuberculosis control in nine African countries

“…To incorporate this into our model, we let the TB disease duration vary as the incidence of TB disease raised to the power of −δ so that when δ = 0, the TB disease duration is the same for all stages of HIV and when δ = 1, the increase in TB incidence is exactly balanced by the decrease in TB disease duration and the prevalence of TB disease is unchanged (SI Appendix, section 3). The estimated TB disease duration in HIV-positive as compared with HIV-negative people, averaged over all stages of HIV infection, is 0.31 (95% CI: 0.18-0.53) (7,(30)(31)(32). Fitting the TB model to trend data for South Africa and setting δ = 0.60 (95% CI: 0.20-0.86) matches the estimated average disease duration.…”

“…HIV-positive people are more likely than HIV-negative people to develop TB but have a shorter TB disease duration and are less infectious for TB (7,(30)(31)(32). The prevalence of TB disease, and hence transmission, is therefore a balance between the increase in TB incidence and the decrease in TB disease duration, allowing for the decrease in TB infectiousness.…”

Effect of HIV-1 Infection on T-Cell–based and Skin Test Detection of Tuberculosis Infection

“…Africa contains 9 of the 22 countries with the highest tuberculosis burden in the world, and the predominant factor driving the increased incidence of tuberculosis in these areas is the high prevalence of HIV (2).…”

Evaluation of public awareness and attitude to pulmonary tuberculosis in a Nigerian rural community

“…4 This study also aimed to determine the level of knowledge, attitude and behavioral practices (KABP) of people towards TB in a rural Nigerian community 5 while evaluating the level of knowledge of TB in different sections of the society in the community, including the medical community. It evaluated the attitude and behavioral practices of the medical community members towards TB and also the awareness of TB patients regarding their disease.…”