title: Controlling HIV epidemics among injection drug users: eight years of Cross-Border HIV prevention interventions in Vietnam and China.
abstract: BACKGROUND
  HIV in Vietnam and Southern China is driven by injection drug use. We have implemented HIV prevention interventions for IDUs since 2002-2003 in Lang Son and Ha Giang Provinces, Vietnam and Ning Ming County (Guangxi), China.
  
  
  METHODS
  Interventions provide peer education and needle/syringe distribution. Evaluation employed serial cross-sectional surveys of IDUs 26 waves from 2002 to 2011, including interviews and HIV testing. Outcomes were HIV risk behaviors, HIV prevalence and incidence. HIV incidence estimation used two methods: 1) among new injectors from prevalence data; and 2) a capture enzyme immunoassay (BED testing) on all HIV+ samples.
  
  
  RESULTS
  We found significant declines in drug-related risk behaviors and sharp reductions in HIV prevalence among IDUs (Lang Son from 46% to 23% [p<0.001], Ning Ming: from 17% to 11% [p = 0.003], and Ha Giang: from 51% to 18% [p<0.001]), reductions not experienced in other provinces without such interventions. There were significant declines in HIV incidence to low levels among new injectors through 36-48 months, then some rebound, particularly in Ning Ming, but BED-based estimates revealed significant reductions in incidence through 96 months.
  
  
  CONCLUSIONS
  This is one of the longest studies of HIV prevention among IDUs in Asia. The rebound in incidence among new injectors may reflect sexual transmission. BED-based estimates may overstate incidence (because of false-recent results in patients with long-term infection or on ARV treatment) but adjustment for false-recent results and survey responses on duration of infection generally confirm BED-based incidence trends. Combined trends from the two estimation methods show sharp declines in incidence to low levels. The significant downward trends in all primary outcome measures indicate that the Cross-Border interventions played an important role in bringing HIV epidemics among IDUs under control. The Cross-Border project offers a model of HIV prevention for IDUs that should be considered for large-scale replication.
authors.affiliation: Abt Associates Inc., Cambridge, Massachusetts, United States of America. ted_hammett@abtassoc.com
authors.forename: Theodore M
authors.initials: TM
authors.lastname: Hammett
authors.forename: Don C
authors.initials: DC
authors.lastname: Des Jarlais
authors.forename: Ryan
authors.initials: R
authors.lastname: Kling
authors.forename: Binh Thanh
authors.initials: BT
authors.lastname: Kieu
authors.forename: Janet M
authors.initials: JM
authors.lastname: McNicholl
authors.forename: Punneeporn
authors.initials: P
authors.lastname: Wasinrapee
authors.forename: J Stephen
authors.initials: JS
authors.lastname: McDougal
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.forename: Donghua
authors.initials: D
authors.lastname: Meng
authors.forename: Ngu
authors.initials: N
authors.lastname: Doan
authors.forename: Huu Nguyen
authors.initials: HN
authors.lastname: Tho
authors.forename: Ngoc Hoang
authors.initials: NH
authors.lastname: Quyen
authors.forename: Van Hoang
authors.initials: VH
authors.lastname: Tren
mesh_terms: D000328:Adult; D002681:China; D003140:Communicable Disease Control / Q000379:methods*; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000453:epidemiology / Q000517:prevention & control*; D006679:HIV Seropositivity / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D055552:Infectious Disease Medicine / Q000379:methods; D007391:International Cooperation; D008297:Male; D010353:Patient Education as Topic / Q000379:methods; D010379:Peer Group; D015995:Prevalence; D012309:Risk-Taking; D015819:Substance Abuse, Intravenous / Q000150:complications*; D011795:Surveys and Questionnaires; D014744:Vietnam