A retrospective analysis of tuberculosis in livestock farmers in Lahore district, Pakistan.

Introduction: Mycobacterium tuberculosis is the main cause of tuberculosis in humans, accounting for numerous illnesses and thousands of fatalities globally. Data regarding the association of various risk factors and TB in livestock farmers in Pakistan is scarce.

Methodology: A retrospective matched case-control study of TB cases was performed in Lahore, Pakistan to investigate the potential risk factors that lead to the development of TB in Pakistani livestock farmers. A total of 170 participants were included in the study. The case was matched with control based on neighborhood and the case-control ratio was kept 1:1. Data were statistically analyzed using R version 4.2.1. Conditional logistic regression was conducted to identify biologically and statistically plausible risk factors associated with the TB outcome among livestock farmers.

Results: In univariable analysis, 10 risk factors were identified (p < 0.05). Gender, age, being married, family type, living in a big family, BCG vaccination status, history of smoking, working at a cattle farm, co-housing with cattle at night, , consumption of raw milk. The multivariable model identified four risk factors i.e., consumption of raw milk (Odds Ratio [OR]: 7.7; 95% Confidence Interval [CI]: 1.95-30.68), living in big family (OR: 6.2; 95% CI: 1.25-30.82) and working at cattle farm (OR: 4.2; 95% CI: 1.08-16.56), while gender was found to be a protective factor with OR < 1 (OR: 0.06; 95% CI: 0.01-0.26).

Conclusions: This study demonstrated that sociodemographic risk factors and exposure to infected cattle can influence the development of TB in farmers.