Longitudinal Trajectories of Alcohol Use in Vietnamese Adults with Hazardous Alcohol Use and HIV.

A three-armed drinking cessation trial in Vietnam found that both a brief and intensive version of an intervention effectively reduced hazardous drinking in people living with HIV. We used group-based trajectory modeling (GBTM) to assess the extent to which findings may vary by latent subgroups distinguished by their unique responses to the intervention. Using data on drinking patterns collected over the 12 months, GBTM identified five trajectory groups, three of which were suboptimal ["non-response" (17.2%); "non-sustained response" (15.7%), "slow response" (13.1%)] and two optimal ["abstinent" (36.4%); "fast response" (17.6%)]. Multinomial logistic regression was used to determine that those randomized to any intervention arm were less likely to be in a suboptimal trajectory group, even more so if randomized to the brief (vs. intensive) intervention. Older age and higher baseline coping skills protected against membership in suboptimal trajectory groups; higher scores for readiness to quit drinking were predictive of it. GBTM revealed substantial heterogeneity in participants' response to a cessation intervention and may help identify subgroups who may benefit from more specialized services within the context of the larger intervention.

Sexual mixing patterns in men who have sex with men: network approaches for smart resource allocation.

BACKGROUND: Age-based sexual mixing patterns in men who have sex with men (MSM) can greatly inform strategic allocation of intervention resources to subsets of the population for the purpose of preventing the greatest number of new HIV infections. METHODS: Egocentric network data collected from MSM participating in annual HIV sentinel surveillance surveys were used to assess age-dependent mixing and to explore its epidemiological implications on the risk of HIV transmission risk (among those HIV-infected) and HIV acquisition risk (among those not infected). RESULTS: Mixing in this sample of 1605 Chinese MSM is relatively age assortative (the average of values expressing the degree of preferential mixing were 2.01 in diagonal cells vs 0.87 in off-diagonal cells). Expected numbers of HIV acquisition were highest in the 20-24years age group; those for HIV transmissions were highest among 25-29year olds. The risk of both acquisition and transmission was highest in age groups that immediately follow the most commonly reported ages of sexual debut in this population (i.e. age 20). CONCLUSIONS: These findings suggest that combination prevention resources should be targeted at younger MSM who are at higher risk of both transmission and acquisition. Programs may also do well to target even younger age groups who have not yet debuted in order to establish prevention effects before risky sexual behaviours begin. More research on optimal strategies to access these harder-to-reach subsets of the MSM population is needed. Findings also support ongoing efforts for public health practitioners to collect network data in key populations to support more empirically driven strategies to target prevention resources.

Expanding syphilis test uptake using rapid dual self-testing for syphilis and HIV among men who have sex with men in China: A multiarm randomized controlled trial.

BACKGROUND: Low syphilis testing uptake is a major public health issue among men who have sex with men (MSM) in many low- and middle-income countries. Syphilis self-testing (SST) may complement and extend facility-based testing. We aimed to evaluate the effectiveness and costs of providing SST on increasing syphilis testing uptake among MSM in China. METHODS AND FINDINGS: An open-label, parallel 3-arm randomized controlled trial (RCT) was conducted between January 7, 2020 and July 17, 2020. Men who were at least 18 years of age, had condomless anal sex with men in the past year, reported not testing for syphilis in the last 6 months, and had a stable residence with mailing addresses were recruited from 124 cities in 26 Chinese provinces. Using block randomization with blocks of size 12, enrolled participants were randomly assigned (1:1:1) into 3 arms: standard of care arm, standard SST arm, and lottery incentivized SST arm (1 in 10 chance to win US$15 if they had a syphilis test). The primary outcome was the proportion of participants who tested for syphilis during the trial period and confirmed with photo verification and between arm comparisons were estimated with risk differences (RDs). Analyses were performed on a modified intention-to-treat basis: Participants were included in the complete case analysis if they had initiated at least 1 follow-up survey. The Syphilis/HIV Duo rapid test kit was used. A total of 451 men were enrolled. In total, 136 (90·7%, 136/150) in the standard of care arm, 142 (94·0%, 142/151) in the standard of SST arm, and 137 (91·3%, 137/150) in the lottery incentivized SST arm were included in the final analysis. The proportion of men who had at least 1 syphilis test during the trial period was 63.4% (95% confidence interval [CI]: 55.5% to 71.3%, p = 0.001) in the standard SST arm, 65.7% (95% CI: 57.7% to 73.6%, p = 0.0002) in the lottery incentivized SST arm, and 14.7% (95% CI: 8.8% to 20.7%, p < 0.001) in the standard of care arm. The estimated RD between the standard SST and standard of care arm was 48.7% (95% CI: 37.8% to 58.4%, p < 0.001). The majority (78.5%, 95% CI: 72.7% to 84.4%, p < 0.001) of syphilis self-testers reported never testing for syphilis. The cost per person tested was US$26.55 for standard SST, US$28.09 for the lottery incentivized SST, and US$66.19 for the standard of care. No study-related adverse events were reported during the study duration. Limitation was that the impact of the Coronavirus Disease 2019 (COVID-19) restrictions may have accentuated demand for decentralized testing. CONCLUSIONS: Compared to standard of care, providing SST significantly increased the proportion of MSM testing for syphilis in China and was cheaper (per person tested). TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1900022409.

Correction: Expanding syphilis test uptake using rapid dual self-testing for syphilis and HIV among men who have sex with men in China: A multiarm randomized controlled trial.

[This corrects the article DOI: 10.1371/journal.pmed.1003930.].

A Statewide Mixed-Methods Study of Provider Knowledge and Behavior Administering Expedited Partner Therapy for Chlamydia and Gonorrhea.

BACKGROUND: Expedited partner therapy (EPT) refers to the practice of having patients diagnosed with chlamydia or gonorrhea deliver medication directly to their partner(s) to treat them presumptively for infection. Although EPT facilitates timely treatment and prevents reinfection, it remains underused. We used findings from key informant interviews to design and implement a statewide survey to estimate knowledge and utilization of EPT and to identify barriers and facilitators to EPT among Minnesota providers. METHODS: From November to December 2020, we carried out 15 interviews with health providers who currently provide EPT and coded interviews by recurring themes. We then conducted a statewide online survey on sexually transmitted infection treatment and barriers to EPT, from December 2020 to March 2021. We disseminated the survey to all licensed Minnesota health providers, and those who reported treating bacterial sexually transmitted infections in the past year were included in the study. RESULTS: Interview themes included the importance of direct provision of partner medication, administrative/pharmacy barriers to treatment, inclusive EPT eligibility, and patient counseling. Of the 623 health providers who completed the online survey, only 70% thought EPT was legal and only 37% currently offer EPT. Of those who did not provide EPT, 78% said they would under certain circumstances. Barriers included concerns about safety/liability of prescribing without a medical examination, administrative concerns about prescriptions, and patient acceptance. CONCLUSIONS: Given that over a quarter of respondents did not know expedited partner therapy (EPT)'s legal status, improving provider education may increase EPT provision. More research is needed on system-level barriers and patient acceptance of solutions identified in this study.

Sexualized Drug Use Among Female Sex Workers from Eight Cities in China: A Cross-Sectional Study.

There is a rich literature on sexualized drug use (i.e., drug use before or during sex) for men who have sex with men but less data from female sex workers (FSW), particularly from low- and middle-income countries. We describe the sexual and reproductive health outcomes in FSW reporting sexualized drug use. In 2019, we conducted a cross-sectional study in eight cities from seven provinces in China. We recruited FSW through community organizations working with sex workers and included those aged 18 years or above, exchanged sex at least once for money or goods in the past three months, and had traded sex for longer than a year. Multivariable logistic regression models were used. In total, 650 women participated: average age was 38.8 years (SD 10.2), 57.1% reported a monthly income over 5000 RMB ($USD 707), and 12.8% completed high school or above. Among participants, 65 (10.0%, 95% confidence interval (CI) 7.8-12.6) reported a history of sexualized drug use. Compared to FSW who never reported a history of sexualized drug use, FSW who reported a history of sexualized drug use had greater odds of working for a manager compared to being self-employed (adjusted odds ratio (AOR) 4.04, 95% CI 2.12-7.69), work in a sauna (AOR 2.43, 95% CI 1.09-5.41), charging a higher price for vaginal sex (AOR 2.15, 95% CI 1.14-4.06), and ever diagnosed with STIs (AOR 4.51, 95% CI 2.61-7.80). One in ten FSW reported sexualized drug use. Although they had similar risk profiles in terms of consistency of condom use and reproductive health outcomes, these women were more likely to report past STIs than those who reported no sexualized drug use. Health workers who work with substance users should devote attention to the sexual practices of their clients to make sure that they have safer sex.

Evaluation of work resumption strategies after COVID-19 reopening in the Chinese city of Shenzhen: a mathematical modeling study.

OBJECTIVES: As China is facing a potential second wave of the epidemic, we reviewed and evaluated the intervention measures implemented in a major metropolitan city, Shenzhen, during the early phase of Wuhan lockdown. STUDY DESIGN: Based on the classic SEITR model and combined with population mobility, a compartmental model was constructed to simulate the transmission of COVID-19 and disease progression in the Shenzhen population. METHODS: Based on published epidemiological data on COVID-19 and population mobility data from Baidu Qianxi, we constructed a compartmental model to evaluate the impact of work and traffic resumption on the epidemic in Shenzhen in various scenarios. RESULTS: Imported cases account for most (58.6%) of the early reported cases in Shenzhen. We demonstrated that with strict inflow population control and a high level of mask usage after work resumption, various resumptions resulted in only an insignificant difference in the number of cumulative infections. Shenzhen may experience this second wave of infections approximately two weeks after the traffic resumption if the incidence risk in Hubei is high at the moment of resumption. CONCLUSION: Regardless of the work resumption strategy adopted in Shenzhen, the risk of a resurgence of COVID-19 after its reopening was limited. The strict control of imported cases and extensive use of facial masks play a key role in COVID-19 prevention.

Syphilis Self-testing: A Nationwide Pragmatic Study Among Men Who Have Sex With Men in China.

BACKGROUND: Syphilis self-testing may help expand syphilis testing among men who have sex with men (MSM). China has rapidly scaled up human immunodeficiency virus (HIV) self-testing, creating an opportunity for integrated syphilis self-testing. However, there is a limited literature on implementing syphilis self-testing. METHODS: A cross-sectional online survey was conducted among Chinese MSM in 2018. Participants completed a survey instrument including sociodemographic characteristics, sexual behaviors, syphilis self-testing, and HIV self-testing history. Multivariable logistic regression was conducted to identify correlates of syphilis self-testing. We also recorded potential harms associated with syphilis self-testing. RESULTS: Six hundred ninety-nine MSM from 89 cities in 21 provinces in China completed the study. A total of 361/699 (51.7%) men tested for syphilis, of whom 174/699 (24.9%) men used syphilis self-testing. Among 174 who had self-tested, 90 (51.7%) reported that the self-test was their first syphilis test and 161 (92.5%) reported that they undertook syphilis self-testing together with HIV self-testing. After adjusting for covariates, syphilis self-testing was correlated with disclosure of sexual orientation to family or friends (adjusted odds ratio [aOR], 1.90; 95% confidence interval [CI], 1.32-2.73), reporting 2-5 male sexual partners (aOR, 1.81; 95% CI, 1.04-3.16), HIV self-testing (aOR, 39.90; 95% CI, 17.00-93.61), and never tested for syphilis in the hospital (aOR, 2.96; 95% CI, 1.86-4.72). Self-reported harms associated with syphilis self-testing were minimal. CONCLUSIONS: Scaling up syphilis self-testing could complement facility-based testing in China among MSM. Self-testing may increase first-time testing and has limited harms. Our findings suggest that syphilis self-testing could be integrated into HIV self-testing services.

Risk attitudes, risky sexual behaviours and willingness to test negative for syphilis using lottery-based financial incentives among Chinese men who have sex with men.

BACKGROUND: Individuals with risk-loving attitudes may be more likely to participate in high-risk sex and gambling. We investigated whether a lottery-based financial incentive to have a negative syphilis test may attract Chinese men who have sex with men (MSM) who practised risky sexual behaviours. METHODS: In July 2018, a national online cross-sectional survey was conducted in China. We collected information on willingness to participate in a lottery-based financial incentive where men were eligible if they tested negative for syphilis, and the minimum prize that would attract them to participate. We used a validated risk attitude scale which asked about the willingness to take risks in six domains, ranging from 0 (avoids taking risk) to 10 (fully prepared to take risks). To avoid multicollinearity, we used principal components analysis to create a 'risk attitude index'. Bivariable and multivariable logistic regression explored factors associated with willingness to test negative for syphilis. RESULTS: 699 MSM enrolled with a median age of 26 years (IQR: 23-30). 70% self-identified as gay and 52% reported ever testing for syphilis. 64% stated they were likely or very likely to test for syphilis linked with a lottery-based incentive. The median desired amount for the lottery had an expected value of ¥10 (US$1.50, IQR: ¥5-¥30). Men who had greater odds of willingness to participate in the lottery-based incentive were those scoring highest on the risk attitude index (adjusted OR (AOR) 2.6, 95% CI 1.5 to 4.3), those reporting more than one sexual partner in the last 3 months (AOR 1.7, 95% CI 1.2 to 2.4), those who had not used condoms during their last sex (AOR 1.5, 95% CI 1.0 to 2.2) and those who ever had group sex (AOR 1.5, 95% CI 1.0 to 2.2). CONCLUSION: Chinese MSM with higher risk attitudes and who reported riskier sexual behaviours indicated greater interest in the concept of a lottery-based incentive for syphilis testing. A lottery-based incentive may be a promising strategy for promoting condom use among risk-loving men.

Detection-Based Monetary Incentives to Improve Syphilis Screening Uptake: Results of a Pilot Intervention in a High Transmission Setting in Southern China.

BACKGROUND: Underscreening of syphilis in clinical settings is a pervasive problem in resource-constrained settings where heavy patient loads and competing health priorities inhibit health providers' ability to meet screening coverage targets. A "detection-based" pay-for-performance (P4P) strategy can incentivize more targeted testing by rewarding providers with a monetary bonus for every confirmed case. METHODS: Five clinics in a high transmission setting of China participated in the 6-month pilot intervention. Seropositive proportions during the P4P intervention were compared with those during the preintervention phase using multilevel logistic regression models adjusted for age and sex of clinic attendees. RESULTS: There were 8423 patients that sought care at 1 of the 6 clinics over the course of the study. Adjusted odds of a positive syphilis screen were greater during the intervention period compared to the preintervention interval (odds ratio, 1.33; 95% confidence interval, 1.14-1.56). Variability in clinic-level effects was substantial given the small number of sites of this pilot study. CONCLUSIONS: Results of this detection-based P4P pilot study demonstrate the feasibility and preliminary effectiveness of this approach for improving syphilis case detection in resource-constrained clinical settings. A fully powered randomized trial is needed to inform the full utility of this approach for improving sexually transmitted disease detection globally.

Leveraging Crowdsourcing for Human Immunodeficiency Virus Testing Posters: A Visual Content Analysis and Cognitive Responses Among Chinese Men Who Have Sex With Men.

INTRODUCTION: Extensive marketing and advertising research has informed a deep understanding of the link between visual design and consumer behaviors, providing a useful framework for assessing associations between human immunodeficiency virus (HIV)-related health posters and viewer responses. METHODS: Crowdsourced posters included finalist submissions from a series of nationwide crowdsourcing contests. Centers for Disease Control (CDC) images were sampled from an online poster database maintained by the National Center for acquired immune deficiency syndrome (AIDS). Once coded according to a set of 27 visual features, posters were shown to an online sample of Chinese men who have sex with men-a group currently experiencing the highest HIV incidence in China-to assess their viewer response. RESULTS: The CDC posters were more likely to use positive facial expressions (65%; 95% confidence interval [CI], 40.9-83.7] vs 12.5%; 95% CI, 2.2-4%) and an educational messaging style (85%; 95% CI, 61.1-96% vs 31.3%; 95% CI, 12.1-58.5). Crowdsourced posters exhibited better craftsmanship than CDC posters (more design simplicity, image diversity, color choice, design quality, and moderate use of text) used more visual metaphors (56.3%; 95% CI, 30.6-79.2 vs 5%; [95% CI, 0.2-26.9%]). Several differences in visual complexity were identified but these lacked statistical significance. CONCLUSION: Crowdsourced posters were of higher craftsmanship, possibly due to their ability to recruit skills of professional designers. The CDC posters' use of positive visual reinforcement (smiling faces) and educational messaging may be a legacy of their role in the early days of the epidemic in disseminating basic HIV/AIDS knowledge and dispelling misinformation. Crowdsourcing posters' used more metaphors, suggesting better ability to leverage in-group codes and language.

Partner Notification Among Persons With Early Syphilis in Shenzhen, China, 2011-2017: Implications for Practice and Policy.

BACKGROUND: Partner notification (PN) is an essential component of syphilis control and is recommended by Chinese Sexually Transmitted Disease guidelines. However, in China, studies examining local practice are limited. This study evaluated PN outcomes among persons with early syphilis infection in an urban district in China. METHODS: From 2011 to 2017, persons diagnosed with early syphilis were asked to participate in an evaluation of supportive patient referral partner services for all recent sex partners, and the contact and case finding indices were determined in Nanshan District, Shenzhen, China. RESULTS: During the study period, 642 index patients with early syphilis reported 1749 sex partners. Of those partners, 678 were potentially contactable and 525 (30%) were contacted. The overall contact index was 0.82. Among the 1749 partners reported, 1108 (63%) were described as casual partners, and only 37 (3%) were contacted (contact index 0.13) compared with 641 partners who were either spouses and regular partners (contact index, 1.37). Among those 525 partners contacted, 418 (80%) were tested, and 205 (39%) were diagnosed with and treated for syphilis. Among those, 9 (4%) were primary, 26 (13%) were secondary, 16 (8%) were early latent, and 154 (49%) were other syphilis infections. The overall case finding index was 0.29. CONCLUSIONS: There is a need to improve PN practices in China, which include developing operational guidelines of PN and to develop and evaluate novel PN ways like using Internet-based strategy.

Correction to: Prepared for PrEP: preferences for HIV pre-exposure prophylaxis among Chinese men who have sex with men in an online national survey.

After publication of the original article [1], the authors would like to add a co-author, Dr. Stephen Pan, who contributed sufficiently to this manuscript.

Promoting routine syphilis screening among men who have sex with men in China: study protocol for a randomised controlled trial of syphilis self-testing and lottery incentive.

BACKGROUND: Men who have sex with men (MSM) bear a high burden of syphilis infection. Expanding syphilis testing to improve timely diagnosis and treatment is critical to improve syphilis control. However, syphilis testing rates remain low among MSM, particularly in low- and middle-income countries. We describe the protocol for a randomised controlled trial (RCT) to assess whether provision of syphilis self-testing services can increase the uptake of syphilis testing among MSM in China. METHODS: Four hundred forty-four high-risk MSM will be recruited online and randomized in a 1:1:1 ratio to (1) standard syphilis self-testing arm; (2) a self-testing arm program enhanced with crowdsourcing and a lottery-based incentive, and (3) a standard of care (control). Self-testing services include a free syphilis self-test kit through the mail at monthly intervals. Participants in the lottery incentive arm will additionally receive health promotion materials generated from an open crowdsourcing contest and be given a lottery draw with a 10% chance to win 100 RMB (approximately 15 US Dollars) upon confirmed completion of syphilis testing. Syphilis self-test kits have step-by-step instructions and an instructional video. This is a non-blinded, open-label, parallel RCT. Participants in each arm will be followed-up at three and 6 months through WeChat (a social media app like Facebook messenger). Confirmation of syphilis self-test use will be determined by requiring participants to submit a photo of the used test kit to study staff via secure data messaging. Both self-testing and facility-based testing will be ascertained by sending a secure photographic image of the completed kit through an existing digital platform. The primary outcome is the proportion of participants who tested for syphilis in the past 3 months. DISCUSSION: Findings from this study will provide much needed insight on the impact of syphilis self-testing on promoting routine syphilis screening among MSM. The findings will also contribute to our understanding of the safety, effectiveness and acceptability of syphilis self-testing. These findings will have important implications for self-testing policy, both in China and internationally. TRIAL REGISTRATION: ChiCTR1900022409 (10 April, 2019).

Gender Identity and Sexual Orientation in Chinese Men Who Have Sex with Men: A Latent Class Analysis.

Men who have sex with men (MSM) are a diverse population yet are often treated as a monolithic risk group. In China, MSM have long been characterized as a "bridge population" of closeted men who are married to (or will marry) women due to sociocultural expectations. Latent class models can inform a more nuanced yet empirical characterization of this population. In total, 1424 eligible respondents recruited online provided self-reported behavioral data. Nine items related to constructs including sexual behaviors, sexual orientation, and gender identity informed the latent class model. Logistic regression was used to measure associations between latent class membership and HIV-related sexual and health-seeking behaviors. Model fit indicated a population structure made up of four classes that we characterized as "Gender nonconforming" (4.3%), "Closeted-unmarried" (29.9%), "Closeted-married" (24.6%), and "Out" (41.2%). Members of the "gender nonconforming" class were more likely to report HIV-related risk behaviors, and "Closeted-unmarried" class members were less likely to report health-seeking behaviors, both relative to "Out" members. The largest latent class was made up of members of the "Out" class, an enlightening revision of a population traditionally viewed as largely closeted men. Two types of "closeted" classes emerged, distinguished by divergent tendencies regarding marriage and health seeking. Findings suggest that current understandings of Chinese MSM are simplistic (regarding closeted behaviors) and too narrow (in its definition of MSM as cisgender men). A more nuanced understanding of MSM subgroups and their heterogeneous risk behaviors will be critical for provision of more meaningful prevention services.

Supernatural Explanatory Models of Health and Illness and HIV Antiretroviral Therapy Use Among Young Men Who Have Sex with Men in China.

BACKGROUND: In China, men who have sex with men (MSM) shoulder a disproportionate HIV burden. Early initiation and adherence to HIV antiretroviral therapy (ART) will be critical to reversing the HIV epidemic in China, but ART usage remains suboptimal among MSM diagnosed with HIV. One understudied but potentially important factor underpinning suboptimal ART usage is personal belief in supernatural explanatory models of health and illness (supernatural explanatory models). This study examines associations between beliefs in supernatural explanatory models and ART usage among MSM in China. METHOD: In 2017, an online survey was distributed nationwide throughout China by gay community-based organizations. Eligible study participants were self-identified MSM between 16 and 30 years old who had tested positive for HIV and who had seen a doctor in the last 2 years. Beliefs in supernatural explanatory models were measured using a three-item scale developed specifically for the Chinese population (range, 3-15). RESULTS: Of 73 participants, the majority were currently using ART (83.6%) and 42.5% expressed some endorsement of belief in supernatural explanatory models. However, among 21 participants with the strongest belief in supernatural explanatory models, prevalence of current ART usage was 61.9%. Stronger belief in supernatural explanatory models was significantly associated with lower likelihood of current ART usage (adjusted odds ratio = 0.52; 95% confidence interval = 0.13-0.75). CONCLUSION: Belief in supernatural explanatory models may be a powerful predictor of ART usage among MSM living with HIV in China. Further studies are needed to corroborate these findings and elucidate mechanisms of association.

"Getting to Zero" Among Men Who Have Sex with Men in China: a Review of the HIV Care Continuum.

PURPOSE OF REVIEW: To review the literature on progress towards UNAIDS 90-90-90 targets for HIV prevention and treatment among men who have sex with men (MSM) in China. RECENT FINDINGS: China has made progress towards UNAIDS 90-90-90 targets among MSM. However, socio-structural barriers, including HIV-related stigma and homophobia, persist at each stage of the HIV care continuum, leading to substantial levels of attrition and high risk of forward HIV transmission. Moreover, access to key prevention tools, such as pre-exposure prophylaxis, is still limited. Multilevel interventions, many using digital intervention, have been shown effective in pragmatic randomized controlled trials in China. Multilevel interventions incorporating digital health have led to significant improvement in engagement of Chinese MSM in the HIV care continuum. However, interventions that address socio-structural determinants, including HIV-related stigma and discrimination, towards Chinese MSM are needed.

Identifying high risk subgroups of MSM: a latent class analysis using two samples.

BACKGROUND: Latent class analyses (LCA) are increasingly being used to target specialized HIV interventions, but generalizability of emergent population structures across settings has yet to be considered. We compare LCA performed on two online samples of HIV negative Chinese men who have sex with men (MSM) to detect more generalizable latent class structures and to assess the extent to which sampling considerations impact the validity of LCA results. METHODS: LCAs were performed on an 1) nationwide online survey which involved no in-person contact with study staff and a 2) sentinel surveillance survey in which participants underwent HIV and syphilis testing in the city of Guangzhou, both conducted in 2014. Models for each sample were informed by risk factors for HIV acquisition in MSM that were common to both datasets. RESULTS: An LCA of the Guangzhou sentinel surveillance data indicated the presence of two relatively similar classes, differing only by the greater tendency of one to report group sex. In contrast an LCA of the nationwide survey identified three classes, two of which shared many of the same features as those identified in the Guangzhou survey, including the fact that they were mainly distinguished by group sex behaviors. The final latent class in the nationwide survey was composed of members with notably few risk behaviors. CONCLUSIONS: Comparisons of the latent class structures of each sample lead us to conclude that the nationwide online sample captured a larger, possibly more representative group of Chinese MSM comprised of a larger, higher risk group and a small yet distinct lower group with few reported behaviors. The absence of a lower risk group in the Guangzhou sentinel surveillance dataset suggests that MSM recruited into studies involving free HIV/STI testing may oversample MSM with higher risk behaviors and therefore greater risk perception. Lastly, two types of higher risk MSM were emergent across both samples distinguished largely by their recent group sex behaviors. Higher odds not only of self-reported HIV infection but also of closeted tendencies and gender fluid identities in this highest risk group suggest that interacting factors drive individual and structural facets of HIV risk.

Correction to: Identifying high risk subgroups of MSM: a latent class analysis using two samples.

Following publication of the original article [1], the author reported his family name has been marked as the first name. His given name is M. Kumi and his family name is Smith.

Prepared for PrEP: preferences for HIV pre-exposure prophylaxis among Chinese men who have sex with men in an online national survey.

BACKGROUND: Pre-exposure prophylaxis (PrEP) is not widely available in China. Previous studies reported low awareness and inconclusive findings on the acceptability of PrEP among Chinese men who have sex with men (MSM). METHODS: We conducted a secondary analysis of an online national survey comparing preferences for oral and long-acting injectable PrEP among MSM and identifying correlates of preferences. The study did not collect detailed information about partner types that may influence negotiated safety and PrEP uptake. RESULTS: Nine-hundred and seventy-nine men from the larger sample of 1045 men responded to the PrEP survey questions. Most men (81.9%) had never heard of PrEP, but reported interest in using PrEP. More participants chose injectable PrEP (36.3%) as their preferred formulation than oral PrEP (24.6%). Men who had at least two HIV tests (adjusted OR = 1.36, 95%CI 1.04, 1.78) more commonly preferred injectable PrEP. CONCLUSION: Our findings may help inform PrEP messaging in areas where PrEP has yet to be scaled up.