Series 1: Behind the Spread: A Scoping Review of Risk Factors for Exposure to Mycobacterium tuberculosis

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Résumé

Background: Tuberculosis (TB) remains a major global health challenge, with transmission
influenced by the incidence of contagious people with TB, the duration of infectivity, and the
probability of contact with susceptible individuals. This review synthesizes recent evidence
on established and emerging risk factors influencing TB transmission, particularly in light
of global trends such as migration, urbanization, and demographic shifts, to guide future
prevention and control strategies. This scoping review maps and synthesizes evidence
from systematic reviews on risk factors for Mycobacterium tuberculosis exposure. Methods:
A preliminary general literature search was conducted in PubMed on 25 August 2024,
using the keywords “tuberculosis,” “risk factors,” and “systematic review.” A subsequent
targeted search focused on systematic reviews published since 2000 that examined social
and environmental determinants of exposure to M. tuberculosis identified in the general
search. Original research and reviews spanning pre-2000 were excluded. Data extraction
and synthesis followed PRISMA-ScR guidelines. Results: Of the 344 systematic reviews
identified, 14 met the eligibility criteria, reporting on key risk factors contributing to the
incidence of contagious people with TB, the duration of infectivity, and the probability
of contact. These risk factors included homelessness, migration, occupational exposure,
urbanization, climate change, and air pollution. The findings emphasize the complex
interrelated role of social and environmental determinants in driving TB transmission.
Conclusion: This review highlights the need for a multi-sectoral approach to TB, as climate
change, air pollution, overcrowding, stigma, and limited healthcare access exacerbate
established risks related to poverty. Effective prevention and control require targeted
interventions that address these interconnected factors.

Mots-clés

Mycobacterium tuberculosis exposure; climate change; air pollution; occupational health; homelessness; migration; multi-sectoral approach