title: The geographic distribution patterns of HIV-, HCV- and co-infections among drug users in a national methadone maintenance treatment program in Southwest China.
abstract: BACKGROUND
  HIV-, HCV- and HIV/HCV co-infections among drug users have become a rapidly emerging global public health problem. In order to constrain the dual epidemics of HIV/AIDS and drug use, China has adopted a methadone maintenance treatment program (MMTP) since 2004. Studies of the geographic heterogeneity of HIV and HCV infections at a local scale are sparse, which has critical implications for future MMTP implementation and health policies covering both HIV and HCV prevention among drug users in China. This study aimed to characterize geographic patterns of HIV and HCV prevalence at the township level among drug users in a Yi Autonomous Prefecture, Southwest of China.
  
  
  METHODS
  Data on demographic and clinical characteristics of all clients in the 11 MMTP clinics of the Yi Autonomous Prefecture from March 2004 to December 2012 were collected. A GIS-based geographic analysis involving geographic autocorrelation analysis and geographic scan statistics were employed to identify the geographic distribution pattern of HIV-, HCV- and co-infections among drug users.
  
  
  RESULTS
  A total of 6690 MMTP clients was analyzed. The prevalence of HIV-, HCV- and co-infections were 25.2%, 30.8%, and 10.9% respectively. There were significant global and local geographic autocorrelations for HIV-, HCV-, and co-infection. The Moran's I was 0.3015, 0.3449, and 0.3155, respectively (P < 0.0001). Both the geographic autocorrelation analysis and the geographic scan statistical analysis showed that HIV-, HCV-, and co-infections in the prefecture exhibited significant geographic clustering at the township level. The geographic distribution pattern of each infection group was different.
  
  
  CONCLUSIONS
  HIV-, HCV-, and co-infections among drug users in the Yi Autonomous Prefecture all exhibited substantial geographic heterogeneity at the township level. The geographic distribution patterns of the three groups were different. These findings imply that it may be necessary to inform or invent site-specific intervention strategies to better devote currently limited resource to combat these two viruses.
authors.affiliation: Department of Epidemiology, School of Public Health, Fudan University, 138 Yi Xue Yuan Road, Shanghai 200032, China. z_yibiao@hotmail.com.
authors.forename: Yi-Biao
authors.initials: YB
authors.lastname: Zhou
authors.forename: Song
authors.initials: S
authors.lastname: Liang
authors.forename: Qi-Xing
authors.initials: QX
authors.lastname: Wang
authors.forename: Yu-Han
authors.initials: YH
authors.lastname: Gong
authors.forename: Shi-Jiao
authors.initials: SJ
authors.lastname: Nie
authors.forename: Lei
authors.initials: L
authors.lastname: Nan
authors.forename: Ai-Hui
authors.initials: AH
authors.lastname: Yang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liao
authors.forename: Xiu-Xia
authors.initials: XX
authors.lastname: Song
authors.forename: Qing-Wu
authors.initials: QW
authors.lastname: Jiang
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D060085:Coinfection / Q000453:epidemiology* / Q000821:virology; D055030:Drug Users / Q000706:statistics & numerical data; D005260:Female; D062306:Geography, Medical; D015658:HIV Infections / Q000453:epidemiology* / Q000821:virology; D006526:Hepatitis C / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D008297:Male; D008691:Methadone / Q000627:therapeutic use; D008875:Middle Aged; D058850:Opiate Substitution Treatment; D015995:Prevalence; D019966:Substance-Related Disorders / Q000188:drug therapy / Q000453:epidemiology* / Q000821:virology
chemical_list: D008691:Methadone