Spatiotemporal Analysis of Men Who Have Sex With Men in Mainland China: Social App Capture-Recapture Method

Short-Term Mobility and Risky Sexual Behaviors Among Men Who Have Sex with Men in Guangdong, China

This study investigated regional differences in short-term mobility patterns among men who have sex with men (MSM) in Guangdong Province, and explored the associations with risky sexual behaviors. An online survey was conducted from June to August 2023, collecting socio-demographic information, intra-provincial mobility details and sexual behaviors. Among 1,808 participants, 60% reported moving within the province over the past six months, primarily for tourism, business/work, or visiting family and friends. Participants were categorized into Pearl River Delta (PRD) and Non-Pearl River Delta (Non-PRD) regions. Significant differences in education level and income were observed between mobile and non-mobile MSM in both areas (p < 0.05). Logistic regression revealed that mobile MSM, relative to non-mobile MSM, were more likely to engage in risky sexual behaviors, with adjusted odds ratios (aORs) for multiple partners, commercial sex, and sexualized drug use ranging from 1.44 to 2.96 in PRD and 2.67 to 4.44 in Non-PRD. Additionally, associations between mobility and behaviors such as having casual partners, group sex, and inconsistent condom use with casual partners were exclusively identified in Non-PRD. These findings indicate that mobility among MSM in Guangdong Province is substantial and follows similar patterns in both regions. Mobile MSM exhibit higher rates of risky sexual behaviors, with notable regional disparities. Addressing the impact of short-term mobility on risky sexual behaviors among MSM is crucial, considering regional variations.

Psychosocial correlates of free Mpox vaccination intention among men who have sex with men in China: model construction and validation

Background

The outbreak of Mpox in China has rendered the promotion of effective preventive measures among susceptible populations particularly crucial. We aimed to explore the correlates and develop a model for Mpox vaccination intention.

Methods

We distributed a questionnaire to a sample of 2403 men who have sex with men to investigate whether they would get a Mpox vaccine. The participants were randomly split into a training set and a testing set in a ratio of 3:1. We screened relevant variables by the least absolute shrinkage and selection operator (LASSO) regression analysis and included them into a Mpox vaccination intention model, which used a multivariate logistic regression analysis and presented the findings as a nomogram. We used the receiver operating characteristic curve, calibration curve, Kolmogorov-Smirnov test, lift test, and population stability index to test the validity and stability of the model.

Results

Of the 2403 participants in our sample, 87.1% intended to get an Mpox vaccine. Five of the thirty-one screened variables, i.e. Mpox knowledge, social support, vaccination internal rewards, vaccination external rewards, and vaccination response efficacy, were included in the vaccination intention model. The model demonstrated strong risk differentiation (Kolmogorov-Smirnov value = 0.46), moderate predictive power (training area under the curve = 0.7709), and good calibration fit, indicating robust performance.

Conclusions

Our proposed model has a good performance and is highly stable, while our findings suggest that governments should design targeted public health strategies, integrating social engagement and leveraging peer and community education to promote Mpox vaccination.

Understanding Awareness, Utilization, and the Awareness-Utilization Gap of HIV PrEP and nPEP Among Young MSM in China

HIV/AIDS remains a significant public health challenge in China, particularly among men who have sex with men (MSM). Pre-Exposure Prophylaxis (PrEP) and non-occupational post-exposure Prophylaxis (nPEP) are effective interventions to reduce HIV transmission in high-risk populations. This study assessed awareness and utilization levels of PrEP and nPEP among young MSM (YMSM) aged 18-29 in China and examined associated factors. A cross-sectional survey of 2,493 YMSM was conducted across six Chinese provinces in September 2022. Participants, recruited via facility-based sampling, completed self-administered online questionnaires distributed by MSM-oriented community-based organizations. Of all the participants, 2,278 (91.4%) were aware of PrEP, and 220 (8.8%) had ever used PrEP; 2,321 (93.1%) were aware of nPEP, and 209 (8.4%) had ever used nPEP. Education level and having recent male sexual partners were positively associated with awareness of PrEP and nPEP, while self-stigma was negatively associated with awareness for both. Among those who had head of PrEP or nPEP, age, having more than 2 male sex partners, and having a history of sexually transmitted diseases (STD) infection were positively associated with the utilization of PrEP and nPEP; inconsistent condom use was associated with less PrEP utilization; monthly income was positively associated with nPEP utilization. Despite high awareness levels, the low utilization of PrEP and nPEP highlights missed opportunities for HIV prevention. Strengthening education on their importance, promoting condom use alongside PrEP/nPEP, reducing stigma, and addressing financial barriers are critical steps toward improving HIV prevention strategies and empowering YMSM to engage with these life-saving interventions.

Spatiotemporal and Behavioral Patterns of Men Who Have Sex With Men Using Geosocial Networking Apps in Shenzhen From Mobile Big Data Perspective: Longitudinal Observational Study

BACKGROUND

The use of geosocial networking apps is linked to increased risky sexual behaviors among men who have sex with men, but their relationship with HIV and other sexually transmitted infections remains inconclusive. Since 2015, the prevalence of app use among men who have sex with men in Shenzhen has surged, highlighting the need for research on their spatiotemporal and behavioral patterns to inform targeted prevention and intervention strategies.

OBJECTIVE

This study aims to investigate the population size, spatiotemporal and behavioral patterns, and mobility of app-using men who have sex with men in Shenzhen using mobile big data. The goal is to inform enhanced and innovative intervention strategies and guide health resource allocation.

METHODS

By leveraging mobile big data application technology, we collected demographic and geographic location data from 3 target apps-Blued (Blued Inc), Jack'd (Online Buddies Inc), and Zank (Zank Group)-over continuous time periods. Spatial autocorrelation (Global Moran I) and hot spot analysis (Getis-Ord Gi) were used to identify the geographic clusters. The Geodetector tool (Chinese Academy of Sciences) was adopted to measure spatially stratified heterogeneity features.

RESULTS

From September 2017 to August 2018, a total of 158,387 males aged 15-69 years in Shenzhen used one of the 3 apps, with the majority (71,318, 45.03%) aged 25-34 years. The app user-to-male ratio was approximately 2.6% among all males aged 15-69 years. The estimated population of app-using men who have sex with men in Shenzhen during this period was 268,817. The geographic distribution of app-using men who have sex with men in Shenzhen was clustered, with hot spots primarily located in central and western Shenzhen, while the distribution of HIV testing and counseling was more concentrated in central-eastern Shenzhen. Approximately 60,202 (38%) app-using men who have sex with men left Shenzhen during the Spring Festival, and 37,756 (62.7%) of them returned after the holiday. The destination distribution showed a relatively centralized flow throughout the country, with the largest mobility within Guangdong province (67.7%), followed by lower mobility to Hunan province (7.9%) and other neighboring provinces (3%-5%), such as Jiangxi, Guangxi, and Hubei Provinces.

CONCLUSIONS

Shenzhen has a large population of men who have sex with men. The variation and inconsistent spatiotemporal distribution of app use and HIV testing and counseling emphasize the need to adapt traditional venue-based prevention and intervention to identified hot spots and to launch outreach initiatives that extend beyond traditional healthcare settings. Given the relatively high internal and interprovincial mobility of app-using men who have sex with men, further smartphone-based behavioral monitoring could provide valuable insights for developing enhanced and innovative HIV prevention and intervention strategies. Moreover, our study demonstrates the potential of mobile big data to address critical research gaps often overlooked by traditional methods.

Mpox Prevention Self-Efficacy and Associated Factors Among Men Who Have Sex With Men in China: Large Cross-Sectional Study

Background

Self-efficacy in mpox (formerly known as monkeypox) prevention plays a pivotal role in promoting preventive behaviors by fostering a sense of control and motivation, especially among men who have sex with men (MSM), the population most affected by mpox in many countries.

Objective

This study aims to assess the mpox prevention self-efficacy among MSM in China and identify factors influencing it, using a validated mpox prevention self-efficacy scale.

Methods

From October 2023 to March 2024, a nationwide cross-sectional study was conducted among MSM (aged ≥18 years) across 6 geographic regions in China using a snowball sampling method. The recruited participants (effective response rate=2403/2481, 96.9%) were asked to complete an anonymous questionnaire designed based on prior knowledge of mpox and social cognitive theory. The mpox prevention self-efficacy scale was evaluated for construct validity using exploratory factor analysis and confirmatory factor analysis, and its reliability was assessed using the Cronbach α coefficient. Univariate and multivariable logistic regression analyses were used to examine the factors associated with mpox prevention self-efficacy among MSM.

Results

A total of 2403 MSM participants were included, with a mean age of 29 (IQR 19-39) years. Of these, 1228 (51.1%) were aged 25-34 years, 1888 (78.6%) held a college degree or higher, and 2035 (84.7%) were unmarried. The median mpox prevention self-efficacy score was 23 (IQR 18-28). Exploratory factor analysis retained 6 items of the mpox prevention self-efficacy scale. Confirmatory factor analysis confirmed a strong model fit (χ²₅=32.1, n=1225; P<.001; comparative fit index=0.991; root mean square error of approximation=0.067; standardized root mean square residual=0.02; goodness-of-fit index=0.992; normed fit index=0.990; incremental fit index=0.991; Tucker-Lewis index=0.974), with all indices within acceptable ranges. The scale demonstrated good internal consistency, with a Cronbach α of 0.859. The positive factors associated with mpox prevention self-efficacy were mpox-related knowledge (OR 1.107, 95% CI 1.070-1.146), perceived risk awareness (OR 1.338, 95% CI 1.132-1.583), and mpox risk perception (OR 1.154, 95% CI 1.066-1.250), while the negative factor was age, with individuals aged 25 years and older exhibiting lower self-efficacy in mpox prevention (25-34 years: OR 0.789, 95% CI 0.642-0.970; 35-44 years: OR 0.572, 95% CI 0.444-0.736; 45 years and older: OR 0.569, 95% CI 0.394-0.823).

Conclusions

These findings highlight the critical role of targeted interventions to enhance mpox prevention self-efficacy, particularly through increasing knowledge, perceived risk awareness, and risk perception. Such interventions are especially important for middle-aged and older MSM, who may experience a decline in self-efficacy. Strengthening self-efficacy in these areas is essential for promoting sustained preventive behaviors, improving mental well-being, and contributing to more effective mpox prevention and control within the MSM community.

Knowledge, concerns, and vaccine acceptance related to Mpox (Monkeypox) among university students in North and Northeast China: An online cross-sectional study

The growing number of Mpox cases in China has posed a challenge to public health. The prevalence of men who have sex with men behaviors among students has been consistently increasing each year in China, accompanied by a high frequency of unprotected anal sex. As crowded places, schools are highly likely to cause an Mpox outbreak among students through long-term close contact. Understanding university students' perceptions about Mpox and willingness to vaccinate play a vital role in implementing preventive measures in schools. This study aimed to assess knowledge, concerns, and vaccine acceptance toward Mpox among university students in North and Northeast China. A cross-sectional study was conducted among 3831 university students from seven universities in North and Northeast China between September 10 and September 25, 2023. This study found a relative insufficiency in Mpox knowledge among university students (71.60%), with less than half expressing concern about the Mpox outbreak (39.57%), and the majority exhibiting a positive attitude to vaccination (76.30%). Multivariate regression analysis revealed that a good knowledge level was associated with age, study discipline, education level, and a high level of concern about Mpox. Male, elderly, or highly educated participants had a low level of concern about Mpox. Participants with a high level of knowledge toward Mpox were more likely to have the vaccination willingness. This study might help governments and schools to understand students' Mpox perceptions and vaccination intentions, enabling them to implement effective measures in addressing the issue of inadequate understanding regarding Mpox among university students.

Comparison of human immunodeficiency virus-related risky sexual behaviors between men who have sex with men only and men who have sex with men and women: A cross-sectional study in Eastern China

Background

Men who have sex with men (MSM) are a significant population contributing to human immunodeficiency virus (HIV) transmission. Nevertheless, few studies have focused on the heterogeneity in MSM. The characteristics of men who have sex with men and women (MSMW) may differ from men who have sex with men only (MSMO).

Methods

From October 2022 to March 2023, a cross-sectional study for MSM was conducted in Eastern China. An electronic questionnaire was used to collect the demographic characteristics and sexual behaviors of participants. A multivariable logistic regression model was used to assess the differences in HIV-related risky sexual behaviors between MSMO and MSMW.

Results

A total of 1993 MSM were enrolled in the study, with 1221 MSMO and 772 MSMW. Compared to MSMW, MSMO reported younger age at first anal sex, higher coerced homosexual experiences, and observed different characteristics of sexual behavior in the past six months. Multivariable analysis indicated that MSMW were more likely to seek casual partners and use stimulants online and offline. MSMW showed inconsistent condom use with online partners (aOR = 0.51, 95 %CI: 0.38-0.68) and more frequent anal sex after drinking (aOR = 2.27, 95 %CI: 1.54-3.35). They also had higher risks of commercial (aOR = 2.47, 95 %CI: 1.71-3.57) and group sexual behaviors (aOR = 1.88, 95 %CI: 1.24-2.83) compared to MSMO.

Conclusion

Our findings suggest that the differential factors may lead MSMW to become a subgroup at high risk of HIV infection. The gender identity and sexual orientation within MSM should be considered when formulating acquired immune deficiency syndrome (AIDS) prevention and control strategies.

Intentions of healthcare seeking and self-isolation for MPOX among men who have sex with men in China: a national cross-sectional study

Linking identified MPOX cases to care is essential for MPOX control. This study aims to investigate the intentions of healthcare seeking and self-isolation for MPOX among men who have sex with men (MSM) in China. A cross-sectional online survey was conducted in early August 2023 in China. Respondents were recruited by community-based organizations (CBOs), collecting information on demographics, health status, behavioural and psychological characteristics. Univariate and multivariate logistic regression analyses were performed to examine the predictors of intentions to seek healthcare and self-isolate for MPOX within the MSM population. A total of 7725 participants were recruited, with a median age of 30 years. 92.21% of the participants would seek healthcare for MPOX-like symptoms, but only 52.50% intended to self-isolate if diagnosed. Intentions to seek healthcare were lower among those with MPOX-like symptoms in the past 3 months (standardized prevalence ratio (SPRs) = 0.82, 95% CI: 0.74-0.89) and the willingness to self-isolate was reduced among those diagnosed with MPOX in the past 3 months (SPRs = 0.65, 95% CI: 0.48-0.87). Participants free of sexually transmitted infections (STIs) and those aware of their HIV status were more likely to seek healthcare and self-isolate than those with STIs or unaware of their HIV status. Regular followers of MPOX information and those perceiving a low risk of infection were more inclined to take preventive measures. These findings highlight the need for targeted MPOX prevention strategies for high-risk groups and the importance of addressing barriers in infectious disease prevention response.

Evolution of HIV Epidemic and Emerging Challenges - China, 1989-2023

Introduction

This study aimed to provide a comprehensive analysis of the human immunodeficiency virus (HIV) epidemiological landscape in China through a historical review and current assessment.

Methods

Data were extracted from China's HIV/AIDS Comprehensive Response Information Management System (CRIMS). Transmission patterns across different phases were visualized using stacked area charts. Geographical correlations between transmission routes were analyzed using scatter plots and Pearson correlation coefficients. The extent and trends of HIV spread among the general population were evaluated using Venn diagrams and Cochran-Armitage tests.

Results

The HIV epidemic in China evolved through four distinct phases: injecting drug user (IDU) dominated (1989-1994), former plasma donor (FPD) outbreak (1995-2005), sexual transmission dominance (2006-2014), and general population spread (2015-present). A strong correlation was observed between provinces reporting high numbers of IDU cases and those with elevated heterosexual transmission (r=0.88, P<0.001). Between 2015 and 2023, 393,926 cases were identified among the general population through non-marital and non-commercial heterosexual contact (NMNCHC). The proportion of general population cases among heterosexual transmissions increased significantly from 46.2% to 55.7% (Z=42.7, P<0.001).

Conclusion

The significant spread of HIV into the general population necessitates the development of targeted prevention strategies for both high-risk and general populations to address emerging epidemiological challenges.

Role of HIV Serostatus Communication on Frequent HIV Testing and Self-Testing Among Men Who Have Sex With Men Who Seek Sexual Partners on the Internet in Zhejiang, China: Cross-Sectional Study

BACKGROUND

Men who have sex with men (MSM) are increasingly using the internet to meet casual sexual partners. Those who do are at higher risk of sexually transmitted diseases. However, little is known about the rates and associations of frequent HIV testing and self-testing among such MSM.

OBJECTIVE

We aimed to examine HIV serostatus communication and perceptions regarding the HIV infection risk of internet-based partners, along with their associations with frequent HIV testing and self-testing.

METHODS

A cross-sectional study was conducted between May 2018 and April 2019 in Zhejiang Province, China. The study participants were assigned male at birth, were aged 18 years or older, had had casual sex with another male found through the internet in the last 6 months, and were HIV-negative. Information was obtained on HIV-testing behavior, along with demographic characteristics, HIV-related knowledge, internet-based behaviors, sexual behaviors with male partners, HIV serostatus communication, and perceptions regarding the HIV infection risk of internet-based partners. Uni- and multivariate logistic regression models were used to measure the associations of HIV testing and self-testing.

RESULTS

The study recruited 281 individuals who had sought casual sexual partners through the internet during the previous 6 months. Of the participants, 61.9% (174/281) reported frequent HIV testing (twice or more frequently) and 50.9% (119/234; 47 with missing values) reported frequent HIV self-testing. MSM who always or usually communicated about the HIV serostatus of internet-based partners in the previous 6 months had 3.12 (95% CI 1.76-5.52) and 2.45 (95% CI 1.42-4.22) times higher odds of being frequently tested or self-tested for HIV, respectively, compared with those who communicated about this issue minimally or not at all.

CONCLUSIONS

There remains a need to improve the frequency of HIV testing and self-testing among internet-based MSM. HIV serostatus communication should be improved within the context of social networking applications to promote frequent HIV testing among internet-based MSM, especially for those who communicated about this issue minimally or not at all.

Place Visitation Data Reveals the Geographic and Racial Disparities of COVID-19 Impact on HIV Service Utilization in the Deep South

BACKGROUND

The COVID-19 pandemic has posed unprecedented pressure to health care systems, and interrupted health care delivery and access including HIV care in the United States' Deep South, which endures a double epidemic of HIV and COVID-19. Ryan White programs cover HIV care services for over half of PLWH in the Deep South. Given the important role of Ryan White programs, examining the visitation changes to Ryan White facilities during the pandemic offers insights into the impact of the pandemic on HIV healthcare utilization.

OBJECTIVES

Analyze the geographic distribution of HIV facility visitors at the county level before and during the pandemic in the nine US states of Deep South (Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas) to reveal the geographic and racial disparity in visitation disruption caused by the pandemic.

METHODS

We first extracted mobile device-based visitation data for Ryan White HIV facilities in the Deep South during 2019 and 2020. To quantify the disruption in visitations during 2020, we calculated the visitation reduction rate (VRR) for each county, using 2019 data as the baseline. Next, we conducted a spatial analysis of the VRR values to uncover geographical disparities in visitation interruptions. To investigate racial disparities, we performed spatial regression analyses with VRR as the dependent variable, and the percentages of Black, Hispanic, and Asian populations as the independent variables. In this analysis, we controlled for potential confounders.

RESULTS

Geographic disparities in visitation reduction were observed, with all nine Deep South states experiencing significant drops. Georgia experienced the highest visitation loss (VRR = -0.58), followed by Texas (-0.47), Alabama (0.47), and Tennessee (-0.46), while South Carolina had the smallest reductions (-0.11). All the regression models consistently revealed racial disparities in visitation interruption. That is, counties with a higher proportion of Black population tended to have higher RW facility visitation reductions.

CONCLUSIONS

Our analysis revealed distinct geographic disparities in visitation interruptions at Ryan White HIV facilities in the Deep South during the COVID-19 pandemic in 2020. Furthermore, we found that the Black/African American population experienced a greater disruption at the county level in the Deep South during this period.

Media Literacy and Its Potential Influence on Mpox-Related Perceptions and Prevention Intentions in China During the 2022 Multi-Country Outbreak of Mpox

Media literacy plays an increasingly important role in health communication during public health emergencies. The present study aimed to investigate the level of media literacy and its association with disease perceptions and behavioral intentions of receiving vaccination services among young men who have sex with men (YMSM) in China during the 2022 multi-country mpox outbreak. The data were from a large-scale cross-sectional survey conducted among 2,493 YMSM aged 18-29 years in six provincial regions in China in September 2022. A total of 2,079 YMSM who had obtained mpox information from social media platforms were included in this study. Correlation analysis and path analysis were conducted. The mean age of the sample was 24.7. After controlling for background variables, significant positive correlations were found in several pairs between media literacy, mpox-related perceptions (including perceived susceptibility to mpox, perceived severity of mpox, perceived benefits of mpox vaccination, and self-efficacy of receiving mpox vaccination), and the behavioral intention of receiving mpox vaccination. The mpox-related perceptions played a significant mediation role in the association between media literacy and intention of receiving mpox vaccination (indirect effect = 0.165, p < .001, effect size = 82.1%). Media literacy is crucial for developing disease perceptions during public health emergencies and may further influence the adoption of preventive measures. As social media platforms have become the main battle field of health communication during disease outbreaks, improvement of media literacy is urgently warranted.

Homosexual identity and network overlap predictors of HIV infection among older men from rural China: a case-control study

Background

The number of newly reported older (≥50 years old) people living with HIV/AIDS in China has been steadily increasing, and heterosexual transmission has been identified as the major route.

Methods

In this study, based on biopsychosocial model, a case-control study (74 cases vs 296 controls) was applied to find out predictors (21 potential ones) of HIV infection among older men from rural China. Binary logistic regression with backward selection was applied.

Results

Out of 21 potential predictors of HIV infection, 4 were confirmed: receiving HIV-related health education (HRHE) (OR 0.449, 95% CI 0.238 to 0.848), self-reported homosexual identity (16.517 (95% CI 1.073 to 254.182)), visiting female sex workers (FSW) (58.427 (95% CI 7.895 to 432.403)), complete non-overlap of intimate social network and sexual network (2.912 (95% CI 1.372 to 6.177)), partial overlap (3.334 (95% CI 1.536 to 7.236)).

Discussion

Findings from this study suggest current comprehensive prevention and control services need to be strengthened to provide effective HRHE including condom use to older men and help them to improve condom use, especially during visiting FSW and among self-reported homosexual older men. Moreover, increasing intimacy in their sexual relationships is necessary.

Behavioral Intention of Receiving Monkeypox Vaccination and Undergoing Monkeypox Testing and the Associated Factors Among Young Men Who Have Sex With Men in China: Large Cross-Sectional Study

BACKGROUND

The worldwide human monkeypox (mpox) outbreak in 2022 mainly affected men who have sex with men (MSM). In China, young men who have sex with men (YMSM) were at a potential high risk of mpox infection due to their sexual activeness and the eased COVID-19 restrictions at the end of 2022.

OBJECTIVE

This study aimed to investigate the behavioral intention of receiving mpox vaccination and undergoing mpox testing in 4 different scenarios and explore their associations with background and behavioral theory-related factors among Chinese YMSM.

METHODS

An online cross-sectional survey was conducted among YMSM aged 18-29 years from 6 representative provinces of China in September 2022. Participants recruited (recruitment rate=2918/4342, 67.2%) were asked to self-administer an anonymous questionnaire designed based on prior knowledge about mpox and classic health behavior theories. Data on the participants' background, mpox knowledge and cognition, mpox vaccination and testing cognition, and the behavioral intention of receiving mpox vaccination and undergoing mpox testing were collected. Descriptive analysis and univariate and multivariate linear regressions were performed. Geodetector was used to measure the stratified heterogeneity of behavioral intention.

RESULTS

A total of 2493 YMSM with a mean age of 24.6 (SD 2.9) years were included. The prevalence of having a behavioral intention of receiving mpox vaccination ranged from 66.2% to 88.4% by scenario, varying in epidemic status and cost. The prevalence of having an mpox testing intention was above 90% in all scenarios regardless of the presence of symptoms and the cost. The positive factors related to vaccination intention included mpox knowledge (ba=0.060, 95% CI 0.016-0.103), perceived susceptibility of mpox (ba=0.091, 95% CI 0.035-0.146), perceived severity of mpox (ba=0.230, 95% CI 0.164-0.296), emotional distress caused by mpox (ba=0.270, 95% CI 0.160-0.380), perceived benefits of mpox vaccination (ba=0.455, 95% CI 0.411-0.498), self-efficacy of mpox vaccination (ba=0.586, 95% CI 0.504-0.668), and having 1 male sex partner (ba=0.452, 95% CI 0.098-0.806), while the negative factor was perceived barriers to vaccination (ba=-0.056, 95% CI -0.090 to -0.022). The positive factors related to testing intention were perceived severity of mpox (ba=0.283, 95% CI 0.241-0.325), perceived benefits of mpox testing (ba=0.679, 95% CI 0.636-0.721), self-efficacy of mpox testing (ba=0.195, 95% CI 0.146-0.245), having 1 male sex partner (ba=0.290, 95% CI 0.070-0.510), and having in-person gatherings with MSM (ba=0.219, 95% CI 0.072-0.366), while the negative factor was emotional distress caused by mpox (ba=-0.069, 95% CI -0.137 to -0.001).

CONCLUSIONS

Among Chinese YMSM, the intention of undergoing mpox testing is optimal, while the mpox vaccination intention has room for improvement. A future national response should raise YMSM's mpox knowledge, disseminate updated information about mpox and preventive measures, improve preventive service accessibility and privacy, and provide advice on positively coping with the associated emotional distress.

The risk of mpox importation and subsequent outbreak potential in Chinese mainland: a retrospective statistical modelling study

BACKGROUND

The 2022-2023 mpox (monkeypox) outbreak has spread rapidly across multiple countries in the non-endemic region, mainly among men who have sex with men (MSM). In this study, we aimed to evaluate mpox's importation risk, border screening effectiveness and the risk of local outbreak in Chinese mainland.

METHODS

We estimated the risk of mpox importation in Chinese mainland from April 14 to September 11, 2022 using the number of reported mpox cases during this multi-country outbreak from Global.health and the international air-travel data from Official Aviation Guide. We constructed a probabilistic model to simulate the effectiveness of a border screening scenario during the mpox outbreak and a hypothetical scenario with less stringent quarantine requirement. And we further evaluated the mpox outbreak potential given that undetected mpox infections were introduced into men who have sex with men, considering different transmissibility, population immunity and population activity.

RESULTS

We found that the reduced international air-travel volume and stringent border entry policy decreased about 94% and 69% mpox importations respectively. Under the quarantine policy, 15-19% of imported infections would remain undetected. Once a case of mpox is introduced into active MSM population with almost no population immunity, the risk of triggering local transmission is estimated at 42%, and would rise to > 95% with over six cases.

CONCLUSIONS

Our study demonstrates that the reduced international air-travel volume and stringent border entry policy during the COVID-19 pandemic reduced mpox importations prominently. However, the risk could be substantially higher with the recovery of air-travel volume to pre-pandemic level. Mpox could emerge as a public health threat for Chinese mainland given its large MSM community.

Behavioral intentions of self-isolation and informing close contacts after developing mpox-related symptoms among young men who have sex with men in China

The 2022 multi-country mpox outbreak raised public concern globally. Self-isolation and informing close contacts after developing mpox-related symptoms are critical measures in controlling the outbreak. This study investigated behavioral intentions of self-isolation and informing close contacts after developing mpox-related symptoms and associated factors among young men who have sex with men (YMSM) aged 18-29 years in China. The cross-sectional study was conducted among 2493 YMSM in six provincial regions in China from September 10th to 30th, 2022. Descriptive and logistic analyses were applied, using the intentions of self-isolation and informing close contacts after developing mpox-related symptoms as binary outcomes. The mean age of the participants was 24.6 (SD = 2.9) years. The prevalence of having intentions of self-isolation and informing close contacts after developing mpox-related symptoms was 88.6% (95% CI: 87.3%-89.9%) and 84.9% (95% CI: 83.5%-86.3%). Participants who were employed (adjusted odds ratio (AOR) = 1.474, 95% CI: 1.035-2.097; AOR = 1.371, 95% CI:1.002, 1.876), had higher mpox knowledge scores (AOR = 1.474, 95% CI: 1.035-2.097; AOR = 1.371, 95% CI: 1.002-1.876), and had higher perceived threats of mpox (AOR = 1.079, 95% CI: 1.030-1.130; AOR = 1.045, 95% CI: 1.002-1.090) were more likely to intend to self-isolate and inform close contacts. Participants who had MSM in-person gatherings in the past 6 months were more likely to intend to self-isolate (AOR = 1.392, 95% CI: 1.066-1.208). Participants with higher depression scores (AOR = 0.968, 95% CI: 0.948-0.989) and self-stigma (AOR = 0.975, 95% CI: 0.954-0.997) were less likely to intend to self-isolate and inform close contacts, respectively. Self-isolation and informing close contacts when developing disease-related symptoms are acceptable measures in response to mpox in China. Strengthening targeted risk communication and self-efficacy, raising disease knowledge, providing mental support, and reducing stigma toward the affected community are warranted.

Quality assessment and sexual health information analysis of mobile dating applications for men who have sex with men: A comprehensive evaluation using the User Version of the Mobile App Rating Scale

Objective

Numerous mobile apps designed for men who have sex with men (MSM) are launched in recent years, potentially serving as crucial platforms for disseminating sexual health information and promoting healthy sexual behaviors. This study aimed to evaluate the quality of dating apps for MSM on the apps market and analyze the sexual health information they provide.

Methods

A systematic search was conducted in major apps platforms in China (including Apple, OPPO, Huawei, and Tencent) to identify current MSM dating apps. Apps fitting the inclusion criteria were independently assessed by two MSM users via using the User Version of Mobile App Rating Scale (uMARS), a user-assessed quality scale for mobile apps.

Results

Fifty mobile apps were identified and assessed, with an overall uMARS score of 3.64 ± 0.53 out of 5. More than half (29 out of 50) of apps included sexual health information.

Conclusions

The overall quality of the apps was satisfactory, whereas significant variations existed in sexual health information content and focus. It is recommended that app developers can further collaborate with public health experts to enhance the accuracy and utility of sexual health information on these platforms.

Gay App Use, Sexuality Traits, and High-Risk Sexual Behaviors Among Men Who Have Sex With Men in China: Mediation Analysis

BACKGROUND

Gay geosocial networking apps, also known as "gay apps," have gained increasing popularity in the men who have sex with men (MSM) community. Certain sexuality traits and gay app use are both associated with high-risk sexual behaviors among MSM. However, little is known about the underlying mechanism of such relationships.

OBJECTIVE

Based on the uses and gratifications theory, this study aimed to test the mediation effect of gay app use on the relationship between sexuality traits (sexual compulsivity and sexual sensation seeking) and high-risk sexual behaviors (multiple sexual partners and unprotected anal intercourse) among MSM.

METHODS

A cross-sectional, multicenter study was conducted in Wuhan and Changsha, China, from August to October 2020. A representative sample of 402 MSM was recruited through respondent-driven sampling. A self-administered web-based structured questionnaire was used to collect data on sociodemographic information, high-risk sexual behaviors, gay app use, sexual compulsivity, and sexual sensation seeking. Path analysis was conducted to assess the mediation effect.

RESULTS

Our study revealed that 67.42% (n=271) of MSM used gay apps for seeking potential sexual partners, with 37.06% (n=149) of them engaging in unprotected anal intercourse, and 45.42% (n=218) of them having multiple sexual partners. Of the participants, 17.16% (n=69) reported significant sexual compulsivity, while 29.10% (n=117) reported significant sexual sensation seeking. Notably, gay app usage partially mediated the relationship between sexual compulsivity and multiple sexual partners but fully mediated the relationship between sexual compulsivity and unprotected anal intercourse. Furthermore, gay app usage partially mediated the relationship between sexual sensation seeking and multiple sexual partners but fully mediated the relationship between sexual sensation seeking and unprotected anal intercourse.

CONCLUSIONS

High-risk sexual behaviors are common among MSM. Most MSM rely on gay apps to find sexual partners, which, when combined with higher levels of sexual compulsivity and sexual sensation seeking, can increase the likelihood of engaging in high-risk sexual behaviors. Therefore, interventions aimed at reducing these behaviors among MSM should focus on addressing the use of gay apps, while also considering the influence of their sexuality traits on gay app use.

Change of sexual behavior among men who have sex with men before, during and after COVID-19 pandemic in China: a cross-sectional study

INTRODUCTION

The COVID-19 epidemic control and prevention strategies affected people's sexual activities and behaviors. Little was known about long-term effects of COVID-19 prevention and control strategies on sexual behaviors among men who have sex with men (MSM). This study aimed to examine changes in risky sexual behaviors of MSM before and after the local epidemic.

METHODS

An online survey was conducted nationwide from June 1 to June 10, 2022. MSM aged 16 years and above, residing in China were recruited through convenience sampling. A generalized estimating equation model with modified Poisson regression was used to analyze changes in multiple sexual partners, unprotected sex, mobility for sexual activity, and recreational substance use before and after the local epidemic.

RESULTS

Compared to the pre-pandemic (36.5%), the prevalence of multiple sexual partners (11.5%) significantly decreased during the local epidemic and then increased after the local epidemic (25.2%) but remained lower than pre-pandemic, as did the prevalence of unprotected sex (31.1%, 19.4%, and 26.1%), mobility for sexual activity (7.5%, 2.8%, and 4.1%) and recreational substance use (47.7%, 27.2%, and 39.5%). Compared to the pre-pandemic, higher declines in the prevalence of risky sexual behaviors during the local epidemic existed among MSM living without a regular partner (44% decrease in unprotected sex and 46% in recreational substance use), with a bachelor's degree and above (70% decrease in multiple sex partners, 39% in unprotected sex, 67% in mobility for sexual activity and 44% in recreational substance use), higher incomes (70% decrease in multiple sex partners), self-identified gay or bisexual/unsure (38-71%), and HIV infection (49-83% decrease respectively in these four indicators). After the local epidemic, the declines in the above indicators compared to the pre-pandemic were correspondingly. And higher declines existed among MSM living without a regular partner (8% decrease in unprotected sex and 13% in recreational substance use), with a bachelor's degree and above (33% decrease in multiple sex partners), higher incomes (55% decrease in mobility for sexual activity), self-identified gay (51% decrease in mobility for sexual activity), and HIV infection (32%, 68%, 24% decrease respectively in unprotected sex, mobility for sexual activity and recreational substance use).

CONCLUSIONS

Risky sexual behaviors reduced considerably during the local epidemic, then seemed rebounded after the outbreak but wouldn't return to pre-pandemic levels. More attention should be paid to vulnerable people with lower socio-economic status, HIV-positive, and sexual minorities for sustained HIV and COVID-19 prevention.

Mpox risk perception and associated factors among Chinese young men who have sex with men: Results from a large cross-sectional survey

The mpox outbreak since 2022 had attacked the community of men who have sex with men (MSM) heavily. This large cross-sectional study investigated the levels and associated factors of mpox risk perception among young MSM (YMSM) aged 18-29 years in six provincial regions of China in September 2022. The participants were recruited via facility-based sampling. Mpox risk perception was measured by perceived susceptibility and perceived severity of mpox. Geodetector was used to measure stratified heterogeneity of mpox risk perception. Univariate and multivariable linear regressions were used to examine the factors associated with mpox risk perception. A total of 2493 participants were included with a mean age of 24.6 years. The proportion of perceiving a susceptibility of mpox under different scenarios ranged 3.7%-17.0% and that of perceiving a severity of mpox ranged 81.6%-83.2%. Stratified heterogeneity of perceived susceptibility, perceived severity, and overall perceived risk of mpox were observed in several characteristics such as study sites, monthly income, risk behaviors, and psychosocial factors. Multivariable regression showed the level of mpox risk perception was positively associated with having in-person gathering activities (ba  = 0.457, 95% CI: 0.208, 0.705), history of HIV infection (ba  = 0.431, 95% CI: 0.028, 0.834), depressive symptoms (ba  = 0.069, 95% CI: 0.049, 0.090), and self-stigma to MSM identity (ba  = 0.047, 95% CI: 0.024, 0.071). The Chinese YMSM showed a high level of perceived severity of mpox but a low level of perceived susceptibility. It is warranted to strengthen targeted risk communication of mpox, develop comprehensive and unstigmatized health messages, and provide mental health support for YMSM.

Effectiveness and cost-effectiveness of human papillomavirus vaccination strategies among men who have sex with men in China: a modeling study

Introduction

The health and economic benefits of human papillomavirus (HPV) vaccination targeted at men who have sex with men (MSM) in developing settings have been rarely assessed. This study aimed to evaluate the effectiveness and cost-effectiveness of different HPV vaccination strategies among MSM in China.

Methods

A Markov model was developed to simulate HPV transmission dynamics among a total of 30.73 million MSM in China. The corresponding natural history included 6 states: susceptible, infected with low-risk subtypes, high-risk subtypes, anogenital warts and anal cancer, and deaths from anal cancer. MSM were divided into three age groups with cut-off points of 27 and 45 years. Alternative vaccination strategies were built by allocating bivalent, quadrivalent, nine-valent, or no vaccine to each of the groups. We generated the prevented infections and deaths by vaccination compared with baseline (no vaccination) and calculated incremental cost-effectiveness ratios (ICERs) to determine the optimal strategy.

Results

The model showed that in 10 years, at baseline, the existing cases of anogenital warts would reach 5,464,225 (IQR, 4,685,708-6,174,175); that of anal cancer would reach 1,922.95 (1,716.56-2,119.93), resulting in 940.55 (732.27-1,141.87) deaths. Under 50% vaccination coverage among one age group, the prevented cases of anogenital warts were maximized with quadrivalent vaccines allocated to MSM aged 27-45 years; that of anal cancer were maximized when offering nine-valent vaccines to the same group. Under 50% vaccination coverage among all groups, the lowest ICER (34,098.09 USD/QALY, 31,146.54-37,062.88) was reached when only quadrivalent vaccines were provided. Based on this strategy, when the annual vaccination rate increased by 30%, the ICER (33,521.75 USD/QALY, 31,040.73-36,013.92) would fall below three times China's per capita GDP. When the vaccine price decreased by 60%, the ICER was reduced to 7,344.44 USD/QALY (4,392.89-10,309.23), indicating good cost-effectiveness taking China's per capita GDP as a threshold.

Conclusions

HPV vaccination can effectively reduce the prevalence and mortality of related diseases among MSM in China, especially quadrivalent vaccines for anogenital warts and nine-valent vaccines for anal cancer. MSM aged 27-45 years were the optimal group for vaccination. Annual vaccination and appropriate adjustment of vaccine price are necessary to further improve the cost-effectiveness.

Development and validation of a risk score for predicting inconsistent condom use with women among men who have sex with men and women

BACKGROUND

Men who have sex with men and women (MSMW) are the most important bridge population for HIV transmission. Condom use plays an important role for HIV infection. However the predictors for condom ues with females are not well characterized.

METHODS

This was a cross-sectional study. Participants were enrolled by four community-based organizations (CBOs) by offline (bathrooms, bars), and online (gay applications, chat room) from April to December 2019. Electronic questionnare was fulfilled after a face-to-face training led by CBOs. We identified predictors of inconsistent condom use with females by creating a risk score based on regression coefficients. We externally validated this score via an independent cross-sectional survey conducted in Zhejiang Province in 2021. A total of 917, 615 MSMW were included in analysis in 2019 and 2021, seperately.

RESULTS

Among 917 MSMW, 73.2% reported heterosexual behavior in the prior 6 months and 38.3% reported inconsistent condom use with females (ICUF) over that time. Compared with heterosexual/unsure MSMW, bisexual MSMW reported more male and female sex partners, higher proportion of inconsistent condom use with males, less commercial sex with males (p < 0.05). Four risky predictors of ICUF were identified: Duration of local residence ≦6 months; more than one male partner in the prior 6 months; inconsistent condom use with males in the prior 6 months; and never heard post-exposure prophylaxis (PEP). The proportions of respondents indicating ICUF in the low- (0), medium- (2-4) and high-risk (6-20) groups (according to our risk scoring system) were 11.7% (14/120), 26.9% (96/357), and 78.1% (125/160), respectively (P_trend < 0.001). In the validation survey, the respective proportions of those reporting ICUF were 13.4% (15/112), 17.8% (24/185) and 87.3% (96/110) (P_trend < 0.001).

CONCLUSIONS

We developed and validated a predictive risk score for ICUF among MSMW; four factors were identified, of which inconsistent condom use with men was the most important. Risk reduction intervention programs should focus on MSM who report inconsistent condom use with males, never heard PEP, having multiple partners and living in local less than 6 months.

Estimating Changes in Population Size and Behavioral Characteristics in Men Who Have Sex With Men Between 2014 and 2019: Longitudinal Study

Background

Men who have sex with men (MSM) are at high risk for HIV infection. Accurate estimation of the population size and monitoring the risk sexual behavioral change of MSM is of great importance to develop targeted HIV prevention and interventions.

Objective

The goal of the research was accurate estimation of the population size and monitoring the risk sexual behavioral change of MSM.

Methods

Street interception investigation methods were conducted among males aged 16 years and older in selected sites in Shenzhen in 2014 and 2019. A population survey was used to estimate the population size of MSM. Logistic regression analysis was applied to evaluate the difference in behavioral characteristics in MSM from 2014 to 2019.

Results

In this study, we surveyed 10,170 participants in 2014, of whom 448 (4.41%, 95% CI 4.01%-4.80%) participants were men who have ever had sex with another man (MSMe) and 229 (2.25%, 95% CI 1.96%-2.54%) were men who had sex with another man in the previous 6 months (MSMa). A total of 10,226 participants were surveyed in 2019, of which 500 (4.90%, 95% CI 4.47%-5.31%) and 208 (2.03%, 95% CI 1.76%-2.31%) participants were MSMe and MSMa, respectively. The results showed that the population size of MSM who are active (MSMa) in Shenzhen was 155,469 (2.29%, 95% CI 2.28%-2.30%) in 2014 and 167,337 (2.05%, 95% CI 2.04%-2.06%) in 2019. It was estimated that there were about 12,005,445 (2.04%, 95% CI 2.04%-2.04%) MSMa in China in 2019. Compared with 2014, the MSMa in 2019 were more likely to seek sex partners through mobile phone apps and less likely to have male and female sex partners in addition to having inconsistent condom use and more than 6 sex partners in the previous 6 months.

Conclusions

In Shenzhen, the proportion of MSMa among the general male population was lower in 2019 than in 2014, and the prevalence of HIV risk behavior was reduced in 2019. Although the preferred platform to find male sex partners among MSM has changed, intervention with high–HIV risk MSM could still help to reduce HIV risk behaviors among the whole MSM group. Because MSM prefer to seek sex partners through mobile phone apps, further study is needed to strengthen internet interventions with high–HIV risk MSM to curb the spread of HIV.

Cost-effectiveness of oral pre-exposure prophylaxis and expanded antiretroviral therapy for preventing HIV infections in the presence of drug resistance among men who have sex with men in China: A mathematical modelling study

Background

Oral pre-exposure prophylaxis (PrEP) and antiretroviral therapy (ART) can effectively prevent HIV infections among men who have sex with men (MSM), but the emergence and transmission of HIV drug-resistance (HIVDR) may compromise their benefits. The costs and benefits of expanding PrEP and ART coverage in the presence of HIVDR in China remain unknown.

Methods

We developed a comprehensive dynamic transmission model incorporating the transmitted (TDR) and acquired (ADR) HIV drug resistance. The model was calibrated by the HIV surveillance data from 2009 to 2019 among MSM in Jiangsu Province, China, and validated by the dynamic prevalence of ADR and TDR. We aimed to investigate the impact of eight intervention scenarios (no PrEP, 20%, 50% or 80% of PrEP, without (77% coverage) or with (90% coverage) expanded ART) on the HIV epidemic trend and cost-effectiveness of PrEP over the next 30 years.

Findings

20% or 50% PrEP + 90% ART would be cost-effective, with an incremental cost-effectiveness ratio (ICER) of 25,417 (95% confidence interval [CI]: 12,390–38,445) or 47,243 (23,756–70,729), and would yield 154,949 (89,662–220,237) or 179,456 (102,570–256,342) incremental quality-adjusted life-years (QALYs) over the next 30 years. No PrEP + 90% ART would yield 125,211 (73,448–176,974) incremental QALYs and be cost-saving. However, 20–80% PrEP + 77% ART and 80% PrEP + 90% ART with ICER of $77,862–$98,338 and $63,332, respectively, and were not cost-effective. A reduction of 64% in the annual cost of oral PrEP would make it highly cost-effective for 50% PrEP + 90% ART.

Interpretation

20% or 50% PrEP + 90% ART is cost-effective for HIV control in the presence of HIVDR. Expanded ART alone may be the optimal policy under the current limited budgets.

Funding

National Natural Science Foundation of China, the National S&T Major Project Foundation of China.

Risks and Opportunities to Ensure Equity in the Application of Big Data Research in Public Health

The big data revolution presents an exciting frontier to expand public health research, broadening the scope of research and increasing the precision of answers. Despite these advances, scientists must be vigilant against also advancing potential harms toward marginalized communities. In this review, we provide examples in which big data applications have (unintentionally) perpetuated discriminatory practices, while also highlighting opportunities for big data applications to advance equity in public health. Here, big data is framed in the context of the five Vs (volume, velocity, veracity, variety, and value), and we propose a sixth V, virtuosity, which incorporates equity and justice frameworks. Analytic approaches to improving equity are presented using social computational big data, fairness in machine learning algorithms, medical claims data, and data augmentation as illustrations. Throughout, we emphasize the biasing influence of data absenteeism and positionality and conclude with recommendations for incorporating an equity lens into big data research.

The Characteristics and Risk Factors of Web-Based Sexual Behaviors Among Men Who Have Sex With Men in Eastern China: Cross-sectional Study

Background

Finding casual sex partners on the internet has been considered a huge challenge for HIV transmission among men who have sex with men (MSM) in China.

Objective

This study aimed to identify the characteristics and risk factors of finding causal sex partners on the internet among MSM in Zhejiang Province, China.

Methods

This was a cross-sectional study. Participants were enrolled by 4 community-based organizations (CBOs) and 10 Voluntary Counselling and Testing (VCT) clinics through advertisements in bathrooms, bars, and gay hook-up apps from June to December 2018. A CBO- or physician-assisted survey was conducted to collected information on finding casual sex partners, perceived HIV infection, and HIV risk behaviors.

Results

Among 767 participants, 310 (40.4%) reported finding causal sex partners on the internet. Factors associated with finding casual sex partners on the internet included watching pornographic videos on the internet more than once a week (adjusted odds ratio [aOR]=1.881, 95% CI 1.201-2.948), discussing “hooking-up online” with friends (aOR=4.018, 95% CI 2.910-5.548), and perceiving that the likelihood of HIV infection among casual sex partners sought on the internet was “medium” (aOR=2.034, 95% CI 1.441-2.873) or “low” (aOR=2.548, 95% CI 1.524-4.259). Among the participants who reported finding casual sex partners on the internet, 30.2% (91/310) reported having unprotected sex with casual sex partners encountered on the internet in the past 6 months. On multivariate logistic regression analyses, knowing the HIV infection status of casual sex partners sought on the internet was significantly associated with performing inserted intercourse (aOR=1.907, 95% CI 1.100-3.306) and a decreased risk of inconsistent condom use (aOR=0.327, 95% CI 0.167-0.642).

Conclusions

Web-based casual sexual behavior is becoming more prevalent, and the rate of unprotected sex among MSM in Zhejiang Province is high. Future HIV prevention approaches should emphasize the importance for MSM to proactively determine the HIV infection status of potential casual sex partners sought on the internet.

Spatiotemporal Dynamic Analysis of A-Level Scenic Spots in Guizhou Province, China

A-level scenic spots are a unique evaluation form of tourist attractions in China, which have an important impact on regional tourism development. Guizhou is a key tourist province in China. In recent years, the number of A-level scenic spots in Guizhou Province has been increasing, and the regional tourist economy has improved rapidly. The spatial distribution evolution characteristics and influencing factors of A-level scenic spots in Guizhou Province from 2005 to 2019 were measured using spatial data analysis methods, trend analysis methods, and geographical detector methods. The results elaborated that the number of A-level scenic spots in all counties of Guizhou Province increased, while in the south it developed slowly. From 2005 to 2019, the spatial distribution in A-level scenic spots were characterized by spatial agglomeration. The spatial distribution equilibrium degree of scenic spots in nine cities in Guizhou Province was gradually developed to reach the “relatively average” level. By 2019, the kernel density distribution of A-level scenic spots had formed the “two-axis, multi-core” layout. One axis was located in the north central part of Guizhou Province, and the other axis ran across the central part. The multi-core areas were mainly located in Nanming District, Yunyan District, Honghuagang District, and Xixiu District. From 2005 to 2007, the standard deviation ellipses of the scenic spots distribution changed greatly in direction and size. After 2007, the long-axis direction of the ellipses gradually formed a southwest to northeast direction. We chose elevation, population density, river density, road network density, tourism income, and GDP as factors, to discuss the spatiotemporal evolution of the scenic spots’ distribution with coupling and attribution analysis. It was found that the river, population distribution, road network density, and the A-level scenic spots’ distribution had a relatively high coupling phenomenon. Highway network density and tourist income have a higher influence on A-level tourist resorts distribution. Finally, on account of the spatiotemporal pattern characteristics of A-level scenic spots in Guizhou Province and the detection results of influencing factors, we put forward suggestions to strengthen the development of scenic spots in southern Guizhou Province and upgrade the development model of “point-axis network surface” to the current “two-axis multi-core” pattern of tourism development. This study can explain the current situation of the spatial development of tourist attractions in Guizhou Province, formulate a regulation mechanism of tourism development, and provide a reference for decision-making to boost the high-quality development of the tourist industry.

HIV incidence among men who have sex with men using geosocial networking smartphone application in Beijing, China: an open cohort study

Background

Sexual transmission among men who have sex with men (MSM) is the dominant route of HIV transmission in China. Extensive use of geosocial networking (GSN) smartphone application (app) has dramatically changed the pattern of sexual behaviors and HIV risk among MSM, but data on HIV incidence and the changing risk behaviors of GSN app-using MSM are limited. We aims to assess the HIV incidence and its correlates among gay GSN app-using MSM in China.

Methods

We constructed an open cohort which was initiated and maintained using a GSN app to assess the HIV incidence among app-using MSM, recruited from June 2017 to December 2018. MSM completed an online questionnaire on their sociodemographic characteristics, sexual behaviors, recreational drug use and sexually transmitted infections status. Then each man had an HIV test, and those tested negatives were enrolled into the cohort. Participants completed follow-ups with additional HIV tests though the app during the study period, and were censored at HIV seroconversion or study end date. HIV incidence was calculated by dividing the sum of observed HIV seroconversions by the observed person-time. Univariate (Chi-square test and Fisher’s exact test) and multivariate (proportional hazards regression) analyses were used to examine correlates of HIV incidence.

Results

A total of 6957 HIV negative MSM were enrolled in the open cohort, 37 seroconversions occurred among 1937 men contributing 1065 observed person-years: HIV incidence was 3.47 per 100 person-years [95% confidence interval (CI): 2.37–4.57]. More than five sexual partners [hazard ratio (HR) = 2.65, 95% CI: 1.04–6.67], and sex with HIV positive partners (HR = 3.82, 95% CI: 1.16–12.64) in the preceding six months were positively associated with HIV seroconversion. Consistent condom use for anal sex (HR = 0.27, 95% CI: 0.07–0.96), and reporting insertive anal sex only (HR = 0.23, 95% CI: 0.08–0.62) in the preceding six months were protective factors for HIV seroconversion.

Conclusions

Tailored interventions targeting app-using MSM are urgently needed given their high risk of HIV. As a new tool for accessing MSM at higher HIV risk, GSN smartphone app could play an important role in HIV research among MSM.

Analysis of the Driving Factors of Active and Rapid Growth Clusters Among CRF07_BC-Infected Patients in a Developed Area in Eastern China

Background

The purpose of this study was to research the molecular transmission and genetic evolutionary characteristics among CRF07_BC-infected patients in a developed area in Eastern China.

Methods

Plasma samples from newly diagnosed HIV-1-positive patients from 2015–2018 and basic demographic and epidemiological information were obtained. Pol sequences from CRF07_BC-infected patients were selected for phylogenetic, molecular transmission network, and Bayesian evolutionary analyses.

Results

Pol sequences were successfully obtained from 258 samples of CRF07_BC. Phylogenetic analysis revealed 2 distinct lineages: lineage 1 (66.3%, 171/258), primarily from men who have sex with men (MSM) and some heterosexual individuals, and lineage 2 (33.7%, 87/258), primarily from heterosexual individuals. Under an optimal genetic distance of 0.01 substitutions/site, 163 individuals (63.2%, 163/258) formed 23 groups comprising 6 clusters and 17 dyads in the networks. A distinctly large and rapidly growing cluster (C1) containing 105 individuals was identified, in which MSM with ≥4 links had quite a high transmission risk (low educational background, active sexual behavior, low sexual protection awareness, etc.). According to Bayesian analyses, most C1 clades formed from 2005 to 2009, most of which were closely geographically related to CRF07_BC epidemic strains from Anhui province.

Conclusions

Here, we elucidated the local transmission characteristics and epidemic pattern of HIV-1 CRF07_BC, revealing that MSM (especially with ≥4 links) may be a significant driver in the formation of active and rapid growth networks in regional CRF07_BC epidemics. Thus, unique region– and risk group–specific transmission network analysis based on a molecular approach can provide critical and insightful information for more effective intervention strategies to limit future HIV-1 transmission.

Location inference for hidden population with online text analysis

Background

Understanding the geographic distribution of hidden population, such as men who have sex with men (MSM), sex workers, or injecting drug users, are of great importance for the adequate deployment of intervention strategies and public health decision making. However, due to the hard-to-access properties, e.g., lack of a sampling frame, sensitivity issue, reporting error, etc., traditional survey methods are largely limited when studying such populations. With data extracted from the very active online community of MSM in China, in this study we adopt and develop location inferring methods to achieve a high-resolution mapping of users in this community at national level.

Methods

We collect a comprehensive dataset from the largest sub-community related to MSM topics in Baidu Tieba, covering 628,360 MSM-related users. Based on users’ publicly available posts, we evaluate and compare the performances of mainstream location inference algorithms on the online locating problem of Chinese MSM population. To improve the inference accuracy, other approaches in natural language processing are introduced into the location extraction, such as context analysis and pattern recognition. In addition, we develop a hybrid voting algorithm (HVA-LI) by allowing different approaches to vote to determine the best inference results, which guarantees a more effective way on location inference for hidden population.

Results

By comparing the performances of popular inference algorithms, we find that the classic gazetteer-based algorithm has achieved better results. And in the HVA-LI algorithms, the hybrid algorithm consisting of the simple gazetteer-based method and named entity recognition (NER) is proven to be the best to deal with inferring users’ locations disclosed in short texts on online communities, improving the inferring accuracy from 50.3 to 71.3% on the MSM-related dataset.

Conclusions

In this study, we have explored the possibility of location inferring by analyzing textual content posted by online users. A more effective hybrid algorithm, i.e., the Gazetteer & NER algorithm is proposed, which is conducive to overcoming the sparse location labeling problem in user profiles, and can be extended to the inference of geo-statistics for other hidden populations.