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.

Objective:To explore the characteristics of HIV-1 genotypic drug resistance for protease-reverse transcriptase (PR-RT) and integrase (IN) among antiretroviral therapy (ART)-naive individuals in Beijing, and provide evidence for clinical diagnosis and treatment.Methods:Newly diagnosed individuals or cases initiating ART were recruited in Beijing covering 2019 to 2020, then pol gene fragments and integrase gene were synchronously amplified and sequenced. Phylogenetic analyses were performed to determine subtypes, and the pol gene and integrase gene sequences were submitted to Stanford University HIV drug resistance database for the interpretation of mutations and drug resistance. Results:Among 168 ART-naive individuals, 93.6% were infected via men who have sex with men (MSM). The top two subtypes were CRF01_AE (41.0%) and CRF07_BC (30.3%), and unique recombinant forms accounted for 16.1% infections. Six individuals carried surveillance drug resistance mutations in PR-RT, with a prevalence of transmitted drug resistance (TDR) at 3.7%. And one case carried nucleoside reverse transcriptase inhibitor mutation of K65R, accompanied with major integrase mutation of T66I (0.6%), conveying resistance to elvitegravir and raltegravir at high and low levels, respectively.Conclusions:The prevalence of transmitted drug resistance was considerably low among ART-naive individuals in Beijing, and the surveillance of genotypic drug resistance should be strengthened, including integrase drug resistance.

Objectives:To understand the prevalence of HIV nucleic acid using internet-based dry blood spots HIV testing strategy in men who had sex with men (MSM) and to probe the factors associated with HIV infection.Methods:Using convenient sampling method, 1 375 MSM were recruited and their dry blood spots samples were collected before being mailed to the laboratories for HIV nucleic acid testing. Results were showed to these MSM on a specific website by inputting their codes to it. Non-conditional binary logistic regression method was used to identify the associated factors on HIV infection.Results:The overall proportions of HIV nucleic acid positives appeared as 9.7 % (131/1 349) and HIV antibody positives as 8.3 % (112/1 349). Fresh infections accounted for 14.5 % (19/131) among the newly-identified HIV nucleic acid positives, and the interval was ranging from 6 to 120 days, between the laboratory testings and the closest date that experiencing high risk behavior. Risk factors that related to HIV infection would include: 30 to 39 years of age (comparing to those under the age of 30, OR=1.88, 95 %CI: 1.07-3.29), ≥8 000 Yuan of monthly income (comparing to those without income, OR=0.42, 95 %CI: 0.19-0.96), inconsistent condom use during anal sexual contacts in the last six months (compared with those who had not anal sex or used condoms consistently in anal sex in the past six months, OR=2.22, 95 %CI: 1.45-3.40), ever use of Rush Poppers (compared with those who never used Rush Poppers, OR=2.33, 95 %CI: 1.49-3.64), addictive drug abuse (compared with those who never abused addictive drugs, OR=5.43, 95 %CI: 2.32-12.69), and not having regular sexual partners (compared with having regular sexual partners, OR=1.74, 95 %CI: 1.13-2.68) etc.. Conclusions:Dry blood spots HIV nucleic acid testing could help to identify the fresh HIV infections at an early stage, so as to prevent further transmission in the MSM population, among which fresh HIV infections accounted for a fairly large proportion. It is necessary to set up programs in reducing the abuse of drugs or Rush Poppers, and to promote condom use and advocate on stable sexual partnership etc., among the MSM population.