Comparing Associated Factors Of HIV Infection Among Drug Users In The Mandatory Detoxification Center, The Voluntary Detoxification Centers And The Communities

Background:The "2008 Report on the global AIDS epidemic" published by UNAIDS showed that intravenous drug use attributed to the majority of the global HIV/AIDS epidemic.In recent years,the number of reported HIV/AIDS cases has been increasing dramatically, and intravenous drug user remained as the main risk factor for HIV infection in China. Studies in different regions reported different prevalence rates of high risk behaviors and HIV infection among drug users.Sometimes,the reported frequencies of the high risk behavior among drug users differed greatly even in the same region and the same time period.It stripped the value of such studies.Objectives:1 To compare demographic characteristics,high risk behaviors and HIV infections among drug users in Mandatory Detoxification Center(MDC),Voluntary Detoxification Centers (VDCs) and communities so that we can assess the difference of their vulnerability and to provide scientific evidence for size estimation of HIV/AIDS epidemic and revision of the surveillance plan.2 To know about the subtypes and to analyze envelop gene fragment sequence among HIV-1 strains.Methods:Drug users were recruited from the MDC,two VDCs and communities in 11 districts in Beijing.The survey was carried out from September to December,2007.Questionnaires were administered focusing on demographic characteristics,drug use behavior and sexual behavior.Blood samples were collected and tested for HIV antibody.Subtype and envelop gene sequence analysis among HIV-1 strains were conducted for those HIV positives using molecular biological analysis software.Data was analyzed using x~2 test, analysis of variance and multivariate logistic regression.Results:1 The drug users in the MDC were the youngest while those in the VDCs were the oldest on average.The proportion of Ugur ethnic group as well as the proportion of illiterate was higher among drug users in MDC while the counterparts were among the drug users in the VDCs.The proportion of Yi ethnic group was higher in the MDC and the communities than that in the VDCs(P＜0.05).Seeking detoxification service in Beijing, 97.2%of the drug users in VDCs were residents of other provinces and 99.0%of them return their hometown in a week.2 Drug users in the MDC and the communities use new type drugs more frequently than those in the VDCs.The proportion of sharing needles or syringes in the last 6 months among the drug users in the MDC was higher than that in the VDCs and the communities.3 Drug users in the communities had more unsafe sex with female/male sex workers, casual sexual partners or homosexual partners than those in the MDC and the VDCs.4 The prevalence rates of HIV infections were 5.2%(41/796),2.7%(14/525) and 1.0% (8/828) respectively among drug users in the MDC,the communities and the VDCs.The difference between the prevalence rates was statistically significant(P＜0.05).5 The associated factors of HIV infection among drug users in MDC include sharing needles or syringes(OR=8.360,95%CI=2.708-25.808),Li ethnic group(OR=53.193, 95%CI=12.249-230.995),Ugur ethnic group(OR=31.881,95%CI=10.640-95.531) and unsafe sex with female/male sex workers(OR=4.347,95%CI=1.314-14.378).The associated factors of HIV infection among drug users in VDCs include sharing needles or syringes(OR=7.572,95%CI=1.222-46.925) and Ugur ethnic group(OR=87.582, 95%CI=13.076-586.632).The associated factors of HIV infection among the communities include sharing needles or syringes(OR=8.074,95%CI=1.832-35.589) and Ugur ethnic group(OR=21.622,95%CI=3.879-120.521).6 The prevalent HIV-1 strain among drug users in Beijing was dominated by three subtypes as CRF07_BC,Thailand B and C.CRF07_BC was identified among drug users in MDC.CRF07_BC,Thailand B and C subtype accounted for 25.0%,25.0%and 50.0% of the HIV-1 strain respectively among drug users in the communities.Conclusion:1 Given the difference of demographic characteristics,behaviors and associated factors between drug users from three types of venues,HIV surveillance among drug users should be carried out in the MDC and the communities.It is not necessary that the VDCs be included in the surveillance system.The proportions of Ugur and Li ethnic group of the samples should be fixed.Size estimation of HIV/AIDS epidemic among drug users in Beijing should be calculated using the HIV infection rate among drug users in MDC as the high estimate and that in the communities as the low estimate.Intervention among drug users in MDC and the communities should focus on methadone maintenance and needle exchange while health education should be carried out in the VDCs.2 The prevalent HIV-1 strain among drug users in Beijing is diverse.CRF07_BC is the dominating subtype.There may be multiple source of transmission for the HIV-1 positives among the drug users in the communities while the HIV-1 positives in the MDC may have the same source of transmission.