“…In Africa, the early identification and utilization of core groups of the population, particularly sex workers, to monitor the epidemic led to a consideration of popula-tion mixing patterns. [33][34][35][36] In efforts to more fully understand the dynamics underlying observed population mixing patterns, researchers have begun to focus on environmental factors, such as migratory labor practices, which facilitate transmission through the geographic diffusion and mixing of populations with varying HIV prevalences. [37][38][39][40][41] For example, investigators in Thailand found that 25% of truckers in their study had had sex with commercial sex workers, as well as with other female partners, such as their wives.…”