title: HIV prevalence and factors associated with HIV infection among male injection drug users under 30: a cross-sectional study in Long An, Vietnam.
abstract: BACKGROUND
  Sufficient targeted HIV prevention activities aiming at reducing HIV transmission within and from an extremely marginalized population of injection drug users (IDUs) must urgently and efficiently be implemented in Vietnam. This study was conducted to facilitate the development of such activities by describing transmission risks of young IDUs and evaluating factors in association with HIV infection.
  
  
  METHODS
  Thirty clusters were selected from 29 hotspot communes in Long An province by probability proportional to size (PPS) sampling method. The snowball technique was used for enrolling participants in each cluster. The cross-sectional association of factors obtained during direct structured interviews to 248 male IDUs aged 14 to 29 years old and with their HIV test results were examined.
  
  
  RESULTS
  The HIV prevalence among the studied IDUs was 32%. Age range of 18-20 years old, low educational level, sharing injection equipment or injection drug use in the other cities were independently associated with HIV serostatus in the multivariate analysis. Sexual behaviors did not differ between HIV-positive and -negative IDUs. Among HIV seropositive IDUs who had sexual contact with primary (n = 37), casual (n = 6), and commercial (n = 15) partners, only 5.4% (n = 2), 33.3% (n = 2), and 46.7% (n = 7), respectively, responded that they had used condoms every time.
  
  
  CONCLUSIONS
  About one-third of young IDUs aged less than 30 identified in the hotspot communes in Long An, Vietnam was found to be infected with HIV, and socio-demographic and injection-related factors might account for the infection risk. Prevailing risky sexual behavior of this extremely marginalized population highlights the need to reduce their high transmission risks as a public health priority.
authors.affiliation: Planning Department, National Institute of Hygiene and Epidemiology, 1 Yersin Hai Ba Trung, Hanoi, Vietnam. thuminh1105@yahoo.com
authors.forename: Thu Minh T
authors.initials: TM
authors.lastname: Tran
authors.forename: Hien T
authors.initials: HT
authors.lastname: Nguyen
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yatsuya
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Hamajima
authors.forename: Akio
authors.initials: A
authors.lastname: Nishimura
authors.forename: Katsuki
authors.initials: K
authors.lastname: Ito
mesh_terms: D000293:Adolescent; D000328:Adult; D016000:Cluster Analysis; D017280:Condoms / Q000706:statistics & numerical data; D003376:Counseling; D003430:Cross-Sectional Studies; D015658:HIV Infections / Q000097:blood / Q000453:epidemiology*; D006679:HIV Seropositivity / Q000453:epidemiology / Q000276:immunology; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016485:Needle Sharing / Q000523:psychology / Q000706:statistics & numerical data; D015995:Prevalence; D012111:Residence Characteristics; D012494:Sampling Studies; D012725:Sexual Behavior / Q000523:psychology / Q000706:statistics & numerical data; D012747:Sexual Partners / Q000523:psychology; D012923:Social Class; D015819:Substance Abuse, Intravenous / Q000150:complications / Q000453:epidemiology / Q000523:psychology; D014744:Vietnam / Q000453:epidemiology