Mixed methods study on latent tuberculosis among agate stone workers and advocacy for testing silica dust exposed individuals in India

Sci Rep. 2024 Jun 15;14(1):13830. doi: 10.1038/s41598-024-64837-4.

Abstract

The 2021 tuberculosis (TB) preventive treatment guidelines in India included silicosis as a screening group, yet latent TB infection (LTBI) testing for silica-dust-exposed individuals is underemphasized. Focusing on an estimated 52 million silica-dust-exposed workers, particularly agate-stone workers in Khambhat, Gujarat, our study aims to estimate LTBI prevalence, identify predictors, and gather insights from TB and silicosis experts. Employing a sequential explanatory mixed-methods approach, a cross-sectional study involved 463 agate-stone workers aged ≥ 20 years in Khambhat, using IGRA kits for LTBI testing. In-depth interviews with experts complemented quantitative findings. Among agate-stone workers, 58% tested positive for LTBI, with predictors including longer exposure, type of work, and BCG vaccination. Our findings reveal a nearly double burden of LTBI compared to the general population, particularly in occupations with higher silica dust exposure. Experts advocate for including silica-dust-exposed individuals in high-risk groups for LTBI testing, exploring cost-effective alternatives like improved skin sensitivity tests, and shorter TB preventive treatment regimens to enhance compliance. Future research should explore upfront TB preventive treatment for silica-dust-exposed individuals with high LTBI prevalence and optimal exposure duration. This study underscores the urgent need for policy changes and innovative approaches to TB prevention among silica-dust-exposed populations, impacting global occupational health strategies.

Keywords: Agate workers; Direct-treat strategy; Dust exposure duration; High risk; India; Key population; Latent tuberculosis infection; Occupational settings; Silicosis; Tuberculosis preventive treatment.

MeSH terms

  • Adult
  • Cross-Sectional Studies
  • Dust* / analysis
  • Female
  • Humans
  • India / epidemiology
  • Latent Tuberculosis* / diagnosis
  • Latent Tuberculosis* / epidemiology
  • Latent Tuberculosis* / prevention & control
  • Male
  • Middle Aged
  • Occupational Exposure* / adverse effects
  • Prevalence
  • Silicon Dioxide*
  • Silicosis* / diagnosis
  • Silicosis* / epidemiology

Substances

  • Silicon Dioxide
  • Dust