Magnitude and associated factors of latent tuberculosis infection due to Mycobacterium tuberculosis complex among high-risk groups in urban Bobo-Dioulasso, Burkina Faso

Objectives: To determine the prevalence and risk factors for latent tuberculosis infection (LTBI) among three high-risk groups – household contacts of TB index cases, healthcare workers and slaughterhouse workers – in Bobo-Dioulasso, Burkina Faso. Methods: Participants were recruited to this cross-sectional study from March to July 2020 after giving informed consent. Sociodemographic, clinical and biological data were collected using a structured questionnaire. The QuantiFERON-TB Gold Plus test (QFT-Plus) and the tuberculin skin test (TST) were used for detection of LTBI. Bivariate and multivariate logistic regression analyses were performed to identify risk factors for LTBI. Results: The prevalence of LTBI among 101 participants (age range 15–68 years) was 67.33% [95% confidence interval (CI) 57.27–76.33] and 84.16% (95% CI 75.55–90.66) based on QFT-Plus and TST results, respectively. Compared with healthcare workers and household contacts of TB index cases, the prevalence of LTBI among slaughterhouse workers was significantly higher for both QTF-Plus (96.8%; P<0.001) and TST (100%; P=0.003). Working in a slaughterhouse [adjusted odds ratio (AOR) 1.095, 95% CI 1.00–2.036], smoking (AOR 4.214, 95% CI 1.051–16.899), ≥15 years of exposure (AOR 5.617, 95% CI 1.202–32.198), having an animal at home (AOR 2.735, 95% CI 1.102–6.789) and protozoal infection (AOR 2.591, 95% CI 1.034–6.491) were significantly associated with LTBI on the QFT-Plus assay. Conclusion: The prevalence of LTBI was high in all three groups, particularly slaughterhouse workers. The risk factors identified could form the basis of targeted intervention.