[Analysis of Spatial Clustering of HIV infected in men who have sex with men in Chongqing of 2004-2015].

Objective: To analyze the spatial clustering characteristics of HIV/AIDS among men who have sex with men (MSM) in Chongqing from January 2004 to December 2015 and understand the HIV/AIDS related behaviors among MSM by interview. Methods: Data related to MSM who were infected with HIV and whose present address were in Chongqing, were collected from Information System on the HIV/AIDS Prevention and Control. Information included the age when the information was inputted, address, occupation, education level, and marital status. The total number of MSM who were infected with HIV and reported was 6 604 in Chongqing. Those with unknown address were ruled out. The spatial autocorrelation analysis and the local spatial autocorrelation analysis were carried out by using ArcGIS 10.3. In addition, in November 2015 and May 2016, using a convenience sampling, we conducted one-on-one interviews among 23 MSM in the Chongqing Center for Disease Control and prevention.

INCLUSION CRITERIA: Receiving voluntary counseling and testing in the urban area of Chongqing and willing to participate in the interview by oral informed consent; male and self-described as MSM. The content of the interview included basic information, sexual orientation, sexual role, the main place of making friends, the main place of sexual behavior, a long-term experience in other provinces and drug abuse. Results: The HIV/AIDS reported number in Chongqing from 2004 to 2015 showed an uptrend, except in 2010. The age distribution of 6 604 cases of HIV positive patients was mainly concentrated in the 15-34 years old, about 68.5% (4 522 cases). There was a positive spatial autocorrelation in MSM, except 2005 (Moran's I=-0.046, P=0.823), form 2004 to 2015, Global Moran's I values were 0.308, 0.254, 0.335, 0.683, 0.673, 0.558, 0.620, 0.673, 0.685, 0.654 and 0.649, respectively; all P values were <0.01. The result of local spatial autocorrelation analysis showed that high-high accumulation area development in Chongqing city was divided into two stages in 2004-2015, which were Yuzhong, Jiangbei, and Shapingba district in 2004-2007 and the expanded Jiulongpo, Nan'an, and Yubei district in 2008-2015. Qualitative interviews results revealed that the age of the respondents was 20-44, and the mainly way of making friends were using mobile phone App and internet (17 participants). Most of the participants (11 participants) were making friends in the bar. The majority of respondents would ask the friends or themselves to use condoms when meeting with them the first time (19 participants), and 8 of respondents reported that they would not use condoms when their old friends refused to use condoms. Conclusion: The HIV infected MSM mainly aged between 15-34 years old and the spatial distribution of HIV/AIDS among MSM was clustered in economically developed main area in Chongqing. MSM began to make friends on the Internet, and could not adhere to using condom, which indicated that we should focus on internet intervention to find more efficacious interventions.