title: Social-environmental factors and protective sexual behavior among sex workers: the Encontros intervention in Brazil.
abstract: OBJECTIVE
  We sought to determine the association of social-environmental factors with condom use and sexually transmitted infections (STIs) among 420 sex workers participating in an STI/HIV prevention study in Corumbá, Brazil, to inform future intervention efforts.
  
  
  METHODS
  Participants provided urine samples for polymerase chain reaction testing of chlamydia and gonorrhea and responded to multi-item scales addressing perceived social cohesion, participation in networks, and access to and management of resources. We conducted multivariate log-linear and negative binomial regression analyses of these data.
  
  
  RESULTS
  Increased social cohesion was inversely associated with number of unprotected sex acts in the preceding week among women (adjusted incidence rate ratio [IRR] = 0.80; P < .01), and there was a marginal association among men (adjusted IRR = 0.41; P = .08). Women's increased participation in social networks was associated with a decrease in frequency of unprotected sex acts (adjusted IRR = 0.83; P = .04), as was men's access to and management of social and material resources (IRR = 0.15; P = .01). Social-environmental factors were not associated with STIs.
  
  
  CONCLUSIONS
  The social context within which populations negotiate sexual behaviors is associated with condom use. Future efforts to prevent STI/HIV should incorporate strategies to modify the social environment.
authors.affiliation: Population Council's Brazil Office, Campinas. salippman@gmail.com
authors.forename: Sheri A
authors.initials: SA
authors.lastname: Lippman
authors.forename: Angela
authors.initials: A
authors.lastname: Donini
authors.forename: Juan
authors.initials: J
authors.lastname: Díaz
authors.forename: Magda
authors.initials: M
authors.lastname: Chinaglia
authors.forename: Arthur
authors.initials: A
authors.lastname: Reingold
authors.forename: Deanna
authors.initials: D
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; D006293:Health Promotion; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D012044:Regression Analysis; D011477:Sex Work; D012725:Sexual Behavior; D012749:Sexually Transmitted Diseases / Q000175:diagnosis / Q000517:prevention & control / Q000652:urine; D012931:Social Environment; D011795:Surveys and Questionnaires; D047568:Unsafe Sex; D055815:Young Adult