Risk of tuberculosis in public transport sector workers, Lima, Peru

SETTING: Delays from symptom onset to the diagnosis and treatment of smear-positive pulmonary tuberculosis (TB) produces possible new cases in persons in close contact with TB cases, especially in confined spaces such as overcrowded public transport, which puts other users and transport workers at risk.

OBJECTIVE: To estimate TB incidence rates in patients of a health micro-network, and the percentage of transport sector workers among TB and multidrug-resistant TB (MDR-TB) patients.

DESIGN: Crude and indirect standardised incidence rates of TB were calculated from an exhaustive analysis of all clinical histories of incident patients in a health micro-network between 1 January 2007 and 30 June 2008. The percentage of transport sector workers and the association between MDR-TB and working in the transport sector were analysed.

RESULTS: Standardised incidence rates for transport sector workers are 2.7–4.5 times higher than those in the total working-age male and global population of the micro-network studied. The association between TB and transport occupation and MDR-TB and transport occupation is high (respectively OR 3.06, 95%CI 2.2–4.2 and OR 3.14, 95%CI 1.1–9.1).

CONCLUSION: These results indicate that the use of informal public transport is a risk factor for TB infection and an occupational risk in countries with characteristics similar to those in Peru.