title: Social and structural factors associated with HIV infection among female sex workers who inject drugs in the Mexico-US border region.
abstract: BACKGROUND
  FSWs who inject drugs (FSW-IDUs) can acquire HIV through high risk sexual and injection behaviors. We studied correlates of HIV infection among FSW-IDUs in northern Mexico, where sex work is quasi-legal and syringes can be legally obtained without a prescription.
  
  
  METHODS
  FSW-IDUs>18 years old who reported injecting drugs and recent unprotected sex with clients in Tijuana and Ciudad Juarez underwent surveys and HIV/STI testing. Logistic regression identified correlates of HIV infection.
  
  
  RESULTS
  Of 620 FSW-IDUs, prevalence of HIV, gonorrhea, Chlamydia, trichomonas, syphilis titers ≥1:8, or any of these infections was 5.3%, 4%, 13%, 35%, 10% and 72%, respectively. Compared to other FSW-IDUs, HIV-positive women were more likely to: have syphilis titers ≥1:8 (36% vs. 9%, p<0.001), often/always inject drugs with clients (55% vs. 32%, p = 0.01), and experience confiscation of syringes by police (49% vs. 28%, p = 0.02). Factors independently associated with HIV infection were syphilis titers ≥1:8, often/always injecting with clients and police confiscation of syringes. Women who obtained syringes from NEPs (needle exchange programs) within the last month had lower odds of HIV infection associated with active syphilis, but among non-NEP attenders, the odds of HIV infection associated with active syphilis was significantly elevated.
  
  
  CONCLUSIONS
  Factors operating in both the micro-social environment (i.e., injecting drugs with clients) and policy environment (i.e., having syringes confiscated by police, attending NEPs) predominated as factors associated with risk of HIV infection, rather than individual-level risk behaviors. Interventions should target unjustified policing practices, clients' risk behaviors and HIV/STI prevention through NEPs.
authors.affiliation: Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America. sstrathdee@ucsd.edu
authors.forename: Steffanie A
authors.initials: SA
authors.lastname: Strathdee
authors.forename: Remedios
authors.initials: R
authors.lastname: Lozada
authors.forename: Gustavo
authors.initials: G
authors.lastname: Martinez
authors.forename: Alicia
authors.initials: A
authors.lastname: Vera
authors.forename: Melanie
authors.initials: M
authors.lastname: Rusch
authors.forename: Lucie
authors.initials: L
authors.lastname: Nguyen
authors.forename: Robin A
authors.initials: RA
authors.lastname: Pollini
authors.forename: Felipe
authors.initials: F
authors.lastname: Uribe-Salas
authors.forename: Leo
authors.initials: L
authors.lastname: Beletsky
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Patterson
mesh_terms: D000328:Adult; D001519:Behavior; D003710:Demography; D004777:Environment; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000453:epidemiology*; D006801:Humans; D008800:Mexico / Q000453:epidemiology; D018671:Needle-Exchange Programs; D016017:Odds Ratio; D011477:Sex Work / Q000706:statistics & numerical data*; D012959:Socioeconomic Factors; D015819:Substance Abuse, Intravenous / Q000150:complications* / Q000453:epidemiology*; D013587:Syphilis / Q000150:complications; D014481:United States / Q000453:epidemiology