Dataset Information

Resistance to Mycobacterium tuberculosis infection among highly TB exposed South African gold miners.

ABSTRACT:

Background

Despite high exposure to Mycobacterium tuberculosis, a small proportion of South African goldminers resist TB infection. We determined, among long-service gold miners i) the proportion who were TB uninfected and ii) epidemiological factors associated with being uninfected.

Methods

We enrolled HIV-negative gold miners aged 33-60 years with ≥15 years' service and no history of TB or silicosis. Miners were defined as TB uninfected if i) QuantiFERON-TB Gold Plus (QFT-Plus) negative or ii) in a stricter definition, QFT-Plus-negative and zero-response on TST and as resisters if they were of Black/African ethnicity and negative on both tests. Logistic regression was used to identify epidemiological factors associated with being TB uninfected.

Results

Of 307 participants with a QFT-Plus result, median age was 48 years (interquartile range [IQR] 44-53), median time working underground was 24 years (IQR 18-28), 303 (99%) were male and 91 (30%) were QFT-Plus-negative. The odds of being TB uninfected was 52% lower for unskilled workers (adjusted odds ratio [aOR] 0.48; 95% confidence interval [CI] 0.27-0.85; p = 0.013). Among 281 participants of Black/African ethnicity, 71 (25%) were QFT-Plus negative. Miners with a BMI ≥30 were less likely to be TB uninfected (OR 0.38; 95% CI 0.18-0.80). Using the stricter definition, 44.3% (136/307) of all miners were classified as either TB uninfected (35; 26%) or infected, (101; 74%) and the associations remained similar. Among Black/African miners; 123 were classified as either TB uninfected (23; 19%) or infected (100; 81%) using the stricter definition. No epidemiological factors for being TB uninfected were identified.

Conclusions

Despite high cumulative exposure, a small proportion of miners appear to be resistant to TB infection and are without distinguishing epidemiological characteristics.

SUBMITTER: Chihota VN

PROVIDER: S-EPMC8932619 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

Resistance to Mycobacterium tuberculosis infection among highly TB exposed South African gold miners.

Chihota Violet N VN Ntshiqa Thobani T Maenetje Pholo P Mansukhani Raoul R Velen Kavindhran K Hawn Thomas R TR Wallis Robert R Grant Alison D AD Churchyard Gavin J GJ Fielding Katherine K

PloS one 20220318 3

<h4>Background</h4>Despite high exposure to Mycobacterium tuberculosis, a small proportion of South African goldminers resist TB infection. We determined, among long-service gold miners i) the proportion who were TB uninfected and ii) epidemiological factors associated with being uninfected.<h4>Methods</h4>We enrolled HIV-negative gold miners aged 33-60 years with ≥15 years' service and no history of TB or silicosis. Miners were defined as TB uninfected if i) QuantiFERON-TB Gold Plus (QFT-Plus) ...[more]

PMID: 35302992

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Dataset Information

Resistance to Mycobacterium tuberculosis infection among highly TB exposed South African gold miners.

Background

Methods

Results

Conclusions

Publications

Resistance to Mycobacterium tuberculosis infection among highly TB exposed South African gold miners.

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