Tuberculosis in transit: risk factors in Tanzania’s high-mobility border regions

Abstract

Introduction: tuberculosis remains a leading infectious killer in low-and middle-income countries. Tanzania's cross-border, high-mobility regions present persistent control challenges. Methods: we recruited 400 adults (200 bacteriologically confirmed pulmonary tuberculosis cases and 200 presumptive non-tuberculosis controls) from six regions between November 2019 and December 2021. Data from structured questionnaires and medical records were analyzed with χ2 tests and multivariate logistic regression. Results: most participants were predominantly male (55.6%) and aged 21-50 years (77.8%). HIV co-infection was the strongest predictor of tuberculosis (AOR=1.52; 95% CI; 1.15-2.21; p=0.003). Household crowding (≥4 residents) (AOR=1.44; 95% CI; 1.03-2.03; p=0.032), poor ventilation (AOR=1.40; 95% CI; 1.01-1.95; p=0.043), and biomass-fuel use (AOR=1.37; 95% CI; 1.00-1.88; p=0.049) independently increased risks for pulmonary tuberculosis. Behavioral factors, smoking (AOR=1.68; 95%CI; 1.12-2.50; p=0.012) and alcohol consumption (AOR=1.57; 95% CI; 1.07-2.31; p=0.021) showed similar associations. Regional tuberculosis prevalence was higher in mobile populations (χ2=6.79; p=0.009); 90% of cases were newly diagnosed patients. Conclusion: pulmonary tuberculosis in Tanzania’s high-mobility regions is driven by HIV co-infection, overcrowded and poorly ventilated dwellings, biomass-fuel smoke, and high-risk behaviors, compounded by diagnostic delays. Strengthening integrated TB-HIV services, enhancing community awareness, and implementing geographically targeted screening are pivotal to accelerating progress toward national End-TB targets.