Use of time-location sampling for systematic behavioral surveillance of truck drivers in Brazil.

We assessed HIV-related risk behavior in a time-location sampling (TLS) interviewer administered survey of male truck drivers at the crossroads of two of the major highways used for trucking in Northeast Brazil (N = 686). Overall, 21.3% had sex while on the road (2.8% unprotected); 12.3% had sex with commercial sex workers (1.4% unprotected); 1.8% had sex with hitch-hikers (0.3% unprotected). Unprotected sex with non-wife partners while on the road was independently associated with stimulant use, lack of religious affiliation and being separated or divorced. Stimulant use may be a particular occupational hazard associated with risk for HIV among truck drivers in Brazil and should be considered as a point of intervention. The TLS sampling approach can form the basis of systematic behavioral surveillance in this highly mobile population.