Objective Data from the HIV/AIDS surveillance sentinel sites was used to identify the recent HIV-1 infections and to estimate the HIV-1 incidence and epidemic trends among intravenous drug users (IDU),MSM,female sex workers and men attending the sexually transmitted disease clinics in Sichuan province.Methods Specimens collected from IDUs,MSM,female sex workers and men attending the sexually transmitted disease clinics sentinel sites were confirmed as HIV-I positive and tested with BED-CEIA.Annual HIV-1 prevalence and incidence rates were calculated and the incidence was adjusted by McNermar method.Results A total number of 194 223 serum specimens were collected and HIV antibody tested,with 5 297 HIV-1 positive.4 640 of the positives underwent BED-CEIA,with 749 identified as recent infections.During 2011-2015,HIV-1 incidence rates of the four types of population appeared as 5.16％ (95％CI:4.65-5.66),0.22％ (95％CI:0.16-0.28),0.57％(95％CI:0.45-0.69),7.53％ (95％CI:6.06-9.01) and 0.44％ (95％CI:0.36-0.53) respectively.Significant differences were seen in the HIV-1 incidence rates.Conclusions The HIV-1 incidence rates of IDUs from other sentinel sites in Sichuan province,female sex workers and men attending the sexually transmitted disease clinics appeared low,showing that the AIDS prevention and control activities worked effectively.However,the HIV-1 incidence of MSM was still at high level and even rising,suggesting that HIV-1 transmission between MSM and IDUs was possible.

The assay was used in HIV/AIDS surveillance sentinel sites to identify recent HIV?1 infection, to estimate HIV?1 incidence and understand the epidemic trends among men who have sex with men during 2011-2015.During 2011-2015, the HIV?1 incidence of men who have sex with men was 5.16%(95%CI: 4.65%-5.66%) in Sichuan Province. According to, a total of 9 cities had been divided into two type of regions: the first type(the proportion of live HIV/AIDS accounts for more than 0.1% of the permanent population, and the number of live HIV/AIDS has reached 500 cases and above) and the second type(the proportion of live HIV/AIDS accounts for 0.03% to 0.100% of the permanent population, and the number of live HIV/AIDS has reached 100-500 cases). During 2011-2015, the HIV?1 incidence of the second type was 4.24% (95%CI:3.72%-4.76%). The HIV?1 incidence of men who have sex with men was at a high level. The spread of HIV?1 to the second region was possible.

The assay was used in HIV/AIDS surveillance sentinel sites to identify recent HIV?1 infection, to estimate HIV?1 incidence and understand the epidemic trends among men who have sex with men during 2011-2015.During 2011-2015, the HIV?1 incidence of men who have sex with men was 5.16%(95%CI: 4.65%-5.66%) in Sichuan Province. According to, a total of 9 cities had been divided into two type of regions: the first type(the proportion of live HIV/AIDS accounts for more than 0.1% of the permanent population, and the number of live HIV/AIDS has reached 500 cases and above) and the second type(the proportion of live HIV/AIDS accounts for 0.03% to 0.100% of the permanent population, and the number of live HIV/AIDS has reached 100-500 cases). During 2011-2015, the HIV?1 incidence of the second type was 4.24% (95%CI:3.72%-4.76%). The HIV?1 incidence of men who have sex with men was at a high level. The spread of HIV?1 to the second region was possible.

The assay was used in HIV/AIDS surveillance sentinel sites to identify recent HIV-1 infection, to estimate HIV-1 incidence and understand the epidemic trends among men who have sex with men during 2011-2015. During 2011-2015, the HIV-1 incidence of men who have sex with men was 5.16%(95%CI: 4.65%-5.66%) in Sichuan Province. According to, a total of 9 cities had been divided into two type of regions: the first type(the proportion of live HIV/AIDS accounts for more than 0.1% of the permanent population, and the number of live HIV/AIDS has reached 500 cases and above) and the second type(the proportion of live HIV/AIDS accounts for 0.03% to 0.100% of the permanent population, and the number of live HIV/AIDS has reached 100-500 cases). During 2011-2015, the HIV-1 incidence of the second type was 4.24% (95%CI: 3.72%-4.76%). The HIV-1 incidence of men who have sex with men was at a high level. The spread of HIV-1 to the second region was possible.