Epidemiological surveillance of informal workers' health in two cities in southeastern Brazil: the experience of the TRAPP-TRAPPURA projects.

Informal labor markets have grown in peripheral countries, accounting for more than 50% of jobs. There is anecdotal evidence of a direct relation between informal sector growth and an increase in the frequency and severity of work-related diseases and injuries. Two sister pilot projects were conducted in Uberaba and Campinas, Brazil to develop population-based epidemiological surveillance of workplace injuries in the informal sector.