title: Findings from Encontros: a multilevel STI/HIV intervention to increase condom use, reduce STI, and change the social environment among sex workers in Brazil.
abstract: BACKGROUND
  Sexually transmitted infection (STI)/HIV prevention programs, which do not modify social structural contexts that contribute to risk of STI/HIV may fail to bring about improvements in health, particularly among groups who experience discrimination and exclusion from public life. We conducted a multilevel intervention with sex workers, including improved clinical care and community-mobilizing strategies to modify social structural factors that shape sexual behavior, to improve condom use and reduce incident STI.
  
  
  METHODS
  We followed 420 sex workers participating in the Encontros intervention in Corumbá, Brazil, between 2003 and 2005. We estimated the effect of the intervention on incident chlamydia and gonorrhea infections and condom use using generalized estimating equations and inverse probability weighting by comparing those who actively engaged in the intervention activities (exposed) with those who were less engaged (unexposed). We also determined the association of participation on reported social cohesion and participation in networks.
  
  
  RESULTS
  Exposed participants had significantly higher odds of reporting consistent condom use with regular clients (odds ratio [OR]: 1.9, 95% confidence interval:1.1-3.3) and nonsignificantly increased odds with both new clients (OR: 1.6, 0.9-2.8) and nonpaying partners (OR: 1.5, 0.9-1.5). The odds of an incident STI were nonsignificantly reduced for exposed participants compared with unexposed (OR: 0.46, 0.2-1.3). Participation was significantly associated with increased perceived cohesion and participation in networks.
  
  
  CONCLUSIONS
  This prospective study provides evidence that multilevel interventions with mobilizing strategies to modify aspects of the social environment can improve condom use, reduce STIs, and increase social cohesion and participation in networks among sex workers.
authors.affiliation: Center for Aids Prevention Studies, University of California San Francisco, San Francisco, CA, USA. sheri.lippman@ucsf.edu
authors.forename: Sheri A
authors.initials: SA
authors.lastname: Lippman
authors.forename: Magda
authors.initials: M
authors.lastname: Chinaglia
authors.forename: Angela A
authors.initials: AA
authors.lastname: Donini
authors.forename: Juan
authors.initials: J
authors.lastname: Diaz
authors.forename: Arthur
authors.initials: A
authors.lastname: Reingold
authors.forename: Deanna L
authors.initials: DL
authors.lastname: Kerrigan
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil; D017280:Condoms / Q000706:statistics & numerical data*; D005260:Female; D015658:HIV Infections / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D021841:Safe Sex; D011477:Sex Work; D060386:Sex Workers; D012725:Sexual Behavior; D012749:Sexually Transmitted Diseases / Q000517:prevention & control*; D012931:Social Environment