Zoonotic Tuberculosis and Dairy Products: Comprehensive Meta-Analysis of Prevalence and Public Health Implications.

BACKGROUND

Tuberculosis (TB) remains a global health concern, with unpasteurized milk serving as a major source of zoonotic Mycobacterium bovis transmission in endemic, low-resource regions.

OBJECTIVE

This meta-analysis investigates the prevalence of human TB cases linked to contaminated dairy products, assesses factors influencing transmission dynamics and identifies actionable strategies to reduce risks.

METHODS

A systematic meta-analysis of TB cases from contaminated dairy consumption was conducted using PubMed, Web of Science and Scopus (2000-2024). Eligible studies reported human TB prevalence. Data were extracted systematically, and statistical analyses (MedCalc) assessed heterogeneity (Cochran's Q, I2). Random- or fixed-effects models were applied, with subgroup, sensitivity and publication bias analyses performed.

RESULTS

This meta-analysis reviewed 25 studies from 2000 to 2024, encompassing 10,508 samples, to assess zoonotic TB linked to dairy consumption. Detection rates ranged widely from 0.77% to 49%, with molecular methods like polymerase chain reaction (PCR) showing higher sensitivity (up to 49%) than culture techniques (21%-35%). Prevalence was greater in TB-endemic areas such as Ethiopia, Mexico and Tanzania, where raw dairy samples outperformed blood diagnostics in positivity. Notably, the highest detection rates were observed in confirmed M. bovis cases with a history of raw milk consumption, underscoring the zoonotic risk in unregulated dairy contexts. Significant heterogeneity (I2 = 98.92%) arose from diagnostic, geographic and population differences. Pooled detection rates were 6.08% (fixed-effects) and 22.90% (random-effects), influenced by unpasteurized milk and poor livestock testing. Publication bias was notable (Egger's p = 0.0009), suggesting overrepresentation of positive small studies, highlighting challenges in standardizing zoonotic TB detection.

CONCLUSION

Zoonotic TB from dairy products is a major concern in endemic areas due to unpasteurized milk and poor veterinary infrastructure. Enhanced pasteurization, standardized diagnostics and better surveillance are key to reducing risks, alongside global food safety standards and public health campaigns to protect vulnerable groups.