The continuing HIV epidemic among men who have sex with men and transgender women in the ASEAN region: implications for HIV policy and service programming.

Men who have sex with men (MSM) in Western urban areas have seen substantive decreases in new diagnoses of HIV infection. This paper explores whether such declines are present among MSM and transgender women (TGW) in Southeast Asia and discusses implications for HIV policies and programming. A scoping review was conducted of scientific publications and selected documents regarding the spread of HIV infection among MSM and TGW in major urban centres of the Association of Southeast Asian Nations (ASEAN) region. Continued high HIV prevalence and incidence among MSM are found in integrated behavioural and biological surveillance (IBBS) and research studies. HIV prevalence among MSM under IBBS decreased only in Bangkok from 28.6% in 2014 to 10.3% in 2018, whereas it was increasing in Kuala Lumpur, Ho Chi Minh City, Vientiane, and Phnom Penh. HIV/AIDS case reports regarding new HIV infection diagnoses among MSM have started to decrease in Singapore since 2011 and have been plateauing in Metropolitan Manila since 2017. Where data were available, it was found that HIV prevalence among TGW was high and if IBBS was conducted, it was increasing. HIV prevalence among TGW under IBBS in Jakarta had risen to 34.0% (2015) and 14.0% (2019) in Phnom Penh. These findings suggest that most ASEAN member states have so far failed to effectively implement and scale-up scientifically proven biomedical HIV prevention measures and counter stigma and discrimination that impedes access to appropriate HIV prevention and treatment services for MSM and TGW.

Daily and Nondaily Oral Preexposure Prophylaxis in Men and Transgender Women Who Have Sex With Men: The Human Immunodeficiency Virus Prevention Trials Network 067/ADAPT Study.

Background: Nondaily dosing of oral preexposure prophylaxis (PrEP) may provide equivalent coverage of sex events compared with daily dosing. Methods: At-risk men and transgender women who have sex with men were randomly assigned to 1 of 3 dosing regimens: 1 tablet daily, 1 tablet twice weekly with a postsex dose (time-driven), or 1 tablet before and after sex (event-driven), and were followed for coverage of sex events with pre- and postsex dosing measured by weekly self-report, drug concentrations, and electronic drug monitoring. Results: From July 2012 to May 2014, 357 participants were randomized. In Bangkok, the coverage of sex events was 85% for the daily arm compared with 84% for the time-driven arm (P = .79) and 74% for the event-driven arm (P = .02). In Harlem, coverage was 66%, 47% (P = .01), and 52% (P = .01) for these groups. In Bangkok, PrEP medication concentrations in blood were consistent with use of ≥2 tablets per week in >95% of visits when sex was reported in the prior week, while in Harlem, such medication concentrations occurred in 48.5% in the daily arm, 30.9% in the time-driven arm, and 16.7% in the event-driven arm (P < .0001). Creatinine elevations were more common in the daily arm (P = .050), although they were not dose limiting. Conclusions: Daily dosing recommendations increased coverage and protective drug concentrations in the Harlem cohort, while daily and nondaily regimens led to comparably favorable outcomes in Bangkok, where participants had higher levels of education and employment. Clinical Trials Registration: NCT01327651.

Young Men Who Have Sex with Men at High Risk for HIV, Bangkok MSM Cohort Study, Thailand 2006-2014.

High HIV incidence has been reported in young men who have sex with men (YMSM) in North America and Western Europe, but there are limited data from Southeast Asia suggesting MSM may be the driver of the HIV epidemic in this region. We described HIV incidence and risk factors among 494 YMSM enrolled in a cohort study in Bangkok, Thailand. The HIV incidence was 7.4 per 100 person-years. In multivariable analysis, reporting use of an erectile dysfunction drug in combination with club drugs, having receptive or both insertive and receptive anal intercourse with men, having hepatitis A infection, having rectal Chlamydia trachomatis, having hepatitis B infection prior to HIV seroconversion, and reporting not always using condoms with male steady partners were significantly associated with HIV incidence in YMSM. Reduction in new HIV infections in YMSM are critical to reach targets set by Thailand and the region.

Challenges and emerging opportunities for the HIV prevention, treatment and care cascade in men who have sex with men in Asia Pacific.

In Asia Pacific, most countries have expanded HIV treatment guidelines to include all those with HIV infection and adopted antiretroviral treatment for prevention (TFP) as a blanket strategy for HIV control. Although the overall epidemic development associated with this focus is positive, the HIV epidemic in men who have sex with men (MSM) is continuing unperturbed without any signs of decline or reversal. This raises doubt about whether TFP as a blanket HIV prevention policy is the right approach. This paper reviews currently available biomedical HIV prevention strategies, national HIV prevention policies and guidelines from selected countries and published data on the HIV cascade in MSM. No evidence for efficacy of TFP in protecting MSM from HIV infection was found. The rationale for this approach is based on assumptions about biological plausibility and external validity of latency-based efficacy found in heterosexual couples. This is different from the route and timing of HIV transmission in MSM. New HIV infections in MSM principally occur in chains of acutely HIV-infected highly sexually active young men, in whom acquisition and transmission are correlated in space and time. By the time TFP renders its effects, most new HIV infections in MSM will have already occurred. On a global level, less than 6% of all reports regarding the HIV care cascade from 1990 to 2016 included MSM, and only 2.3% concerned MSM in low/middle-income countries. Only one report originated from Asia Pacific. Generally, HIV cascade data in MSM show a sobering picture of TFP in engaging and retaining MSM along the continuum. Widening the cascade with a preventive extension, including pre-exposure prophylaxis, the first proven efficacious and only biomedical HIV prevention strategy in MSM, will be instrumental in achieving HIV epidemic control in this group.

Psychosocial and Behavioral Characteristics of High-Risk Men Who Have Sex with Men (MSM) of Unknown HIV Positive Serostatus in Bangkok, Thailand.

HIV prevalence remains high in men who have sex with men (MSM) in Bangkok. Even though resources for HIV testing and treatment are available for all, a large proportion of MSM still do not get HIV tested. We studied high risk MSM who are unaware of their HIV status to help maximize effectiveness of our resources. Convenience sampling was conducted among MSM who came for HIV testing at the Thai Red Cross Anonymous Clinic and two popular drop-in centers in Bangkok. Inclusion criteria were MSM aged >18 years, have not been tested positive for HIV, who reported ≥1 of the following in the previous 6 months: condomless sex with a male, being a sex worker, or having a sexual transmitted infection diagnosis. Audio-Computer-Assisted Self-Interview was used to assess psychosocial profile, sexual risks, and HIV testing patterns prior to being informed of their HIV positive status. Among 499 high-risk MSM enrolled, the median age was 24.8 years and 112 (22 %) tested HIV-positive. Among the HIV-positive participants, 92 % self-identified as gay (versus bisexual), 39 % attained a bachelors degree or higher, 65 % had monthly income 10,000-29,999 baht ($280-830 USD), 10 % had vaginal or anal sex with a woman in the past 12 months, 39 % had condomless receptive sex with men and 21 % went to Lat Phrao to find a sexual partner. Compared to HIV negative MSM, HIV-positive MSM had less HIV testing: 31 % had ever been tested for HIV, 12 % had been tested in the past 6 months; but were more likely to guess correctly their positive status (31 %). Regarding psychosocial variables among HIV-positive MSM, 7 % had regular methamphetamine use in the past 3 months, 10 % had >2 sources of discrimination, and 8 % had >2 sources of discrimination due to being MSM. In multivariable model, age<30 year old, self-identified as gay, had monthly income <50,000 baht ($1400 USD), had anal sex with men in past 12 months, had >2 sources of discrimination because of being MSM, did not get HIV test in past 6 months, and guess of positive HIV were significantly associated with HIV positive status. Young MSM with lower socioeconomic status (SES) should be prioritized for innovative approaches to promoting awareness and uptake of HIV testing. Societal stigmatization of MSM should be addressed as a potential barrier to uptake of voluntary HIV testing. Resilience factors among these marginalized MSM who still test frequently and remain HIV-negative despite residing in a context with community viral loads and discrimination should also be studied in order to curb the HIV epidemic in Bangkok.

Incidence of and temporal relationships between HIV, herpes simplex II virus, and syphilis among men who have sex with men in Bangkok, Thailand: an observational cohort.

BACKGROUND: High HIV incidence has been detected among men who have sex with men (MSM) in Thailand, but the relationship and timing of HIV, herpes simplex virus 2 (HSV-2), and syphilis is unknown. This analysis measures incidence, temporal relationships, and risk factors for HIV, HSV-2, and syphilis among at-risk MSM in the Bangkok MSM Cohort Study. METHODS: Between April 2006 and December 2010, 960 men negative for HIV, HSV-2, and syphilis at entry enrolled and contributed 12-60 months of follow-up data. Behavioral questionnaires were administered at each visit; testing for HIV antibody was performed at each visit, while testing for syphilis and HSV-2 were performed at 12 month intervals. We calculated HIV, HSV-2, and syphilis incidence, assessed risk factors with complementary log-log regression, and among co-infected men, measured temporal relationships between infections with Kaplan-Meier survival analysis and paired t-test. RESULTS: The total number of infections and incidence density for HIV, HSV-2, and syphilis were 159 infections and 4.7 cases/100 PY (95 % Confidence Interval (CI): 4.0-5.4), 128 infections and 4.5/100 PY (95 % CI: 3.9-5.5), and 65 infections and 1.9/100 PY (95 % CI: 1.5-2.5), respectively. Among men acquiring >1 infection during the cohort period, mean time to HIV and HSV-2 infection was similar (2.5 vs. 2.9 years; p = 0.24), while syphilis occurred significantly later following HIV (4.0 vs. 2.8 years, p < 0.01) or HSV-2 (3.8 vs. 2.8 years, p = 0.04) infection. The strongest independent predictor of any single infection in adjusted analysis was acquisition of another infection; risk of syphilis (Adjusted Hazards Ratio (AHR) = 3.49, 95 % CI: 1.89-6.42) or HIV (AHR = 2.26, 95 % CI: 1.47-3.48) acquisition during the cohort was significantly higher among men with incident HSV-2 infection. No single independent behavioral factor was common to HIV, HSV-2, and syphilis acquisition. CONCLUSION: HIV and HSV-2 incidence was high among this Thai MSM cohort. However, acquisition of HIV and co-infection with either HSV-2 or syphilis was low during the time frame men were in the cohort. Evaluation of behavioral risk factors for these infections suggests different risks and possible different networks.

Prevalence of Anal Human Papillomavirus Vaccine Types in the Bangkok Men Who Have Sex With Men Cohort Study.

BACKGROUND: The quadrivalent human papillomavirus (qHPV) and 9 valent (nHPV) vaccine are licensed for males to prevent anal HPV-associated dysplasia and cancer caused by HPV types 6, 11, 16, and 18 (qHPV) and additional types 33, 35, 45, 52, and 58 (nHPV), respectively. Both conditions are common in HIV-infected and HIV-uninfected men who have sex with men (MSM). It is not well documented which anal HPV vaccine types are most prevalent in Southeast Asia. METHODS: A convenience sample of 400 anal swabs were obtained from 200 HIV-infected and 200 HIV-uninfected sexually active Bangkok MSM Cohort Study participants. After swab collection in PreservCyt (Cytyc Corp, Marlborough, MA), the media was stored at -80°C until processing. DNA was extracted, amplified by polymerase chain reaction, denatured, and then hybridized to probes for 37 HPV types and ß-globin. RESULTS: The mean participant age was 25.6 years (range, 18-55 years); the mean CD4 T-cell count was 410 cells/mm in the HIV-infected participants. Among all swab samples, 386 (192 HIV-positive and 194 HIV-negative) had adequate ß-globin for HPV genotype testing. Anal HPV type was detected in 44.3% of participants whose samples underwent genotype testing. Both qHPV and nHPV types were more frequently detected in HIV-infected compared with HIV-uninfected (42.2% vs. 23.2% [P < 0.01], 50.0% vs. 24.2% [P < 0.01]), respectively). There were no significant relationships between social behaviors (alcohol use, drug use) or sexual behaviors (number of partners, condom usage, sexual positioning) and anal HPV prevalence. CONCLUSIONS: The prevalence of anal vaccine HPV types in Thai MSM was similar to that reported in MSM from Western populations and has a similar distribution by HIV status. Targeting young MSM with vaccination could offer protection against HPV vaccine types.

Prevalence and Correlates of Chlamydia trachomatis and Neisseria gonorrhoeae by Anatomic Site Among Urban Thai Men Who Have Sex With Men.

BACKGROUND: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infection are prevalent among men who have sex with men (MSM) and may infect multiple anatomic sites. We measured site-specific prevalence and correlates of CT and NG infection among Bangkok MSM Cohort Study participants. METHODS: In April 2006 to November 2010, 1744 men enrolled in the Bangkok MSM Cohort Study. Participants provided historical information and underwent physical examination. Rectal, urethral, and pharyngeal CT and NG screening were performed by nucleic acid amplification and/or culture. Logistic regression was used to identify correlates of site-specific CT, NG, and coinfection. RESULTS: Among 1743 participants, 19.2% were infected with CT and/or NG. CT, NG, and CT-NG coinfection were detected in 11.6%, 4.6%, and 2.9%, of participants, respectively. Rectal, urethral, and pharyngeal CT infections were detected in 9.5%, 4.5%, and 3.6% of cases. N. gonorrhoeae was present at these sites in 6.1%, 1.8%, and 0.5% of cases. Most infections were asymptomatic (CT: 95.3%, NG: 83.2%). Rectal CT and NG infections were mutually associated (CT: adjusted odds ratio [AOR], 5.4; 95% confidence interval [CI], 3.4-8.7; NG: AOR, 2.4; 95% CI, 1.1-5.2) and independently associated with HIV infection (CT: AOR, 1.6, 95% CI, 1.0-2.4; NG: AOR, 2.0, 95% CI, 1.3-3.1). Numerous behavioral correlates of infection were observed. CONCLUSIONS: CT and NG infections are highly prevalent among MSM in Bangkok, most frequently affect the rectum, and are most often asymptomatic. Routine screening of asymptomatic MSM for CT and NG infection should include rectal sampling and focus on men with HIV and a history of other sexually transmitted infections.

A novel acute HIV infection staging system based on 4th generation immunoassay.

BACKGROUND: Fourth generation (4thG) immunoassay (IA) is becoming the standard HIV screening method but was not available when the Fiebig acute HIV infection (AHI) staging system was proposed. Here we evaluated AHI staging based on a 4thG IA (4thG staging). FINDINGS: Screening for AHI was performed in real-time by pooled nucleic acid testing (NAT, n=48,828 samples) and sequential enzyme immunoassay (EIA, n=3,939 samples) identifying 63 subjects with non-reactive 2nd generation EIA (Fiebig stages I (n=25), II (n=7), III (n=29), IV (n=2)). The majority of samples tested (n=53) were subtype CRF_01AE (77%). NAT+ subjects were re-staged into three 4thG stages: stage 1 (n=20; 4th gen EIA-, 3rd gen EIA-), stage 2 (n=12; 4th gen EIA+, 3rd gen EIA-), stage 3 (n=31; 4th gen EIA+, 3rd gen EIA+, Western blot-/indeterminate). 4thG staging distinguishes groups of AHI subjects by time since presumed HIV exposure, pattern of CD8+ T, B and natural killer cell absolute numbers, and HIV RNA and DNA levels. This staging system further stratified Fiebig I subjects: 18 subjects in 4thG stage 1 had lower HIV RNA and DNA levels than 7 subjects in 4thG stage 2. CONCLUSIONS: Using 4th generation IA as part of AHI staging distinguishes groups of patients by time since exposure to HIV, lymphocyte numbers and HIV viral burden. It identifies two groups of Fiebig stage I subjects who display different levels of HIV RNA and DNA, which may have implication for HIV cure. 4th generation IA should be incorporated into AHI staging systems.

Global epidemiology of HIV infection in men who have sex with men.

Epidemics of HIV in men who have sex with men (MSM) continue to expand in most countries. We sought to understand the epidemiological drivers of the global epidemic in MSM and why it continues unabated. We did a comprehensive review of available data for HIV prevalence, incidence, risk factors, and the molecular epidemiology of HIV in MSM from 2007 to 2011, and modelled the dynamics of HIV transmission with an agent-based simulation. Our findings show that the high probability of transmission per act through receptive anal intercourse has a central role in explaining the disproportionate disease burden in MSM. HIV can be transmitted through large MSM networks at great speed. Molecular epidemiological data show substantial clustering of HIV infections in MSM networks, and higher rates of dual-variant and multiple-variant HIV infection in MSM than in heterosexual people in the same populations. Prevention strategies that lower biological transmission and acquisition risks, such as approaches based on antiretrovirals, offer promise for controlling the expanding epidemic in MSM, but their potential effectiveness is limited by structural factors that contribute to low health-seeking behaviours in populations of MSM in many parts of the world.

Hepatitis A and hepatitis B infection prevalence and associated risk factors in men who have sex with men, Bangkok, 2006-2008.

Despite the availability of safe and effective vaccines, little is known about prevalence and risk factors for hepatitis A (HAV) and hepatitis B virus (HBV) infection among Thai men who have sex with men. The prevalence of HAV and HBV infection among men who have sex with men cohort in Bangkok was assessed. Baseline blood specimens were drawn and demographic and behavioral data were collected. Bivariate and multivariate logistic regression analysis was used to analyze risk factors for prevalent HAV and HBV infection. One thousand two hundred ninety-nine Thai men who have sex with men 18 years and older were enrolled. Among those with results, 349/1,291 (27.0%) had evidence of past or current hepatitis A infection. Of the 1,117 (86.5%) men with unambiguous HBV test results, 442 (39.6%) had serologic evidence of past/current infection, 103 (9.2%) were immune due to hepatitis B vaccination, 572 (51.2%) had no evidence of immunological exposure to HBV or vaccine. Of those with past/current HBV infection, 130 (29.4%) were HIV positive. Age >35 years was independently associated with both HAV and HBV infection. University education was protective against both HAV and HBV infection. Increased alcohol consumption, number of lifetime male sexual partners ≥10, and prevalent HIV infection were also independently associated with HBV infection. The prevalence of past/current HAV and HBV infection was high in Bangkok men who have sex with men. Age-cohorts with a higher prevalence of hepatitis B vaccine induced immunity may be expected in the future. Hepatitis A and B vaccination is recommended.

Central nervous system viral invasion and inflammation during acute HIV infection.

BACKGROUND: Understanding the earliest central nervous system (CNS) events during human immunodeficiency virus (HIV) infection is crucial to knowledge of neuropathogenesis, but these have not previously been described in humans. METHODS: Twenty individuals who had acute HIV infection (Fiebig stages I-IV), with average 15 days after exposure, underwent clinical neurological, cerebrospinal fluid (CSF), magnetic resonance imaging, and magnetic resonance spectroscopy (MRS) characterization. RESULTS: HIV RNA was detected in the CSF from 15 of 18 subjects as early as 8 days after estimated HIV transmission. Undetectable CSF levels of HIV (in 3 of 18) was noted during Fiebig stages I, II, and III, with plasma HIV RNA levels of 285651, 2321, and 81978 copies/mL, respectively. On average, the CSF HIV RNA level was 2.42 log(10) copies/mL lower than that in plasma. There were no cases in which the CSF HIV RNA level exceeded that in plasma. Headache was common during the acute retroviral syndrome (in 11 of 20 subjects), but no other neurological signs or symptoms were seen. Intrathecal immune activation was identified in some subjects with elevated CSF neopterin, monocyte chemotactic protein/CCL2, and interferon γ-induced protein 10/CXCL-10 levels. Brain inflammation was suggested by MRS. CONCLUSIONS: CSF HIV RNA was detectable in humans as early as 8 days after exposure. CNS inflammation was apparent by CSF analysis and MRS in some individuals during acute HIV infection.

HIV prevalence and incidence among men who have sex with men and transgender women in Bangkok, 2014-2018: Outcomes of a consensus development initiative.

To reach its goal of ending AIDS by 2030, Thailand has adopted antiretroviral treatment as prevention and HIV pre-exposure prophylaxis for men who have sex with men (MSM) and transgender women (TGW) as its core HIV control strategy. However, in the absence of reliable epidemiologic indicators, the impact of these policies on the course of the HIV epidemic in these groups remains unknown. To help answer this question, we formulated an HIV epidemic consensus initiative for Bangkok, Thailand, to analyze epidemiologic and program data and reach agreement between experts and stakeholders on the evolving state of the HIV epidemic among MSM and TGW. A customized Delphi process was used to consult and consolidate viewpoints of experts and stakeholders. Experts presented and discussed HIV prevalence and incidence data from recent and ongoing studies among MSM and TGW in Bangkok (2014 to 2018) during a meeting with stakeholders representing government, donors, and civil society. Agreement about the course of the HIV epidemic among MSM and TGW was attained by voting consensus. Based on presented data, meeting participants agreed that HIV prevalence and incidence had decreased among Bangkok MSM from 2014 to 2018. Despite these declines, HIV prevalence and incidence were found to remain high. This was particularly the case among younger MSM. Participants agreed that there was no evidence for a decrease in HIV prevalence and incidence among Bangkok TGW. Introduction of antiretroviral treatment as prevention and HIV pre-exposure prophylaxis may have contributed to these declines. However, HIV prevalence and incidence remained high, and no signs of a decrease were reported among Bangkok TGW. At the current rate of new HIV infections in MSM and TGW, Thailand will not reach its goal of ending AIDS by 2030. This HIV consensus initiative may serve as a model for building agreement and advocacy on epidemiologic and program data and their implications for a large metropolitan city.

Factors associated with HIV testing history and returning for HIV test results among men who have sex with men in Thailand.

We evaluated factors associated with HIV testing history and returning for HIV test results among 2,049 Thai men who have sex with men. Of men, 50.3% reported prior HIV testing and 24.9% returned for HIV test results. Factors associated with prior HIV testing were male sex work, older age, employed, living away from the family, insertive anal sex role, history of drug use and having heard of effective HIV/AIDS treatment. Factors associated with returning for HIV test results were male sex work, older age, lack of a family confidant, history of sexually transmitted infections, and testing HIV negative in this study.

HIV prevalence, risk behavior, hormone use and surgical history among transgender persons in Thailand.

While Male-to-female transgender persons (TG) are believed to often engage in sex work and have high HIV infection risk, little is known about demographics, surgical and hormone use history, risk behaviors and HIV prevalence. Between March and October 2005, 474 TG from Bangkok, Chiangmai, and Phuket were surveyed using venue-day-time sampling. Of 474 participants, overall HIV prevalence was 13.5%. Most participants had completed at least secondary or vocational education (79.2%), gender self-identified as female (89.0%), had received money, gifts or valuables for sex (60.8%), and reported hormone use (88.6%). Surgical history was taken from 325 participants. Of these, 68.6% reported some form of surgery and 11.1% had undergone penile-vaginal reconstructive surgery. In multivariate analysis, being recruited from a park/street; older age, anal sex role identification as "versatile" and anal sex debut before age 13 were independently associated with HIV prevalence. The development, implementation and evaluation of culturally appropriate sexual health interventions for Thai TG is urgently needed.

Correlates of forced sex among populations of men who have sex with men in Thailand.

Although forced sex is a correlate of HIV infection, its prevalence and associated risks are not well described among men who have sex with men (MSM) in developing-country settings. Between March and October 2005, we assessed the prevalence of forced sex and correlates among populations of MSM (this includes general MSM, male sex workers, and male-to-female transgender persons) in Thailand using a community-based sample. Participants were enrolled from venues around Bangkok, Chiangmai, and Phuket using venue day-time sampling. Handheld computer-assisted self-interviewing was used to collect demographic and behavioral data and logistic regression evaluated factors associated with forced sex, defined as ever being forced to have sexual intercourse against one's will. Of the 2,049 participants (M age, 24.8 years), a history of forced sex was reported by 376 (18.4%) men and, of these, most were forced by someone they knew (83.8%), forced more than once (67.3%), and had first occurrence during adolescence (55.1%). In multivariate analysis, having a history of forced sex was significantly associated with being recruited in Phuket, classification as general MSM or transgender (versus classification as male sex worker), drug use, increased number of male sexual partners, and buying sex. The findings in our assessment were consistent with assessments from Western countries. Longitudinal studies are needed to understand the mechanisms of the relationships between forced sex correlates found in our assessment and HIV acquisition and transmission risks.

A scoping review of HIV epidemiologic, sociocultural and programmatic studies related to transgender women and men who have sex with men in Cambodia, 1999-2019.

BACKGROUND: Cambodia is widely credited for its successful HIV epidemic control. However, in recent years there have been signs of increasing HIV prevalence among men who have sex with men (MSM) and transgender women (TGW). This paper reviews HIV epidemiological, social science and HIV program implementation studies conducted over the past 20 years to explore possible reasons for the rising HIV prevalence among these groups and to formulate recommendations for improved policies, HIV programmatic interventions and further research. METHODS: For this scoping review, we searched the PubMed and Google Scholar databases for scientific publications related to HIV and MSM and TGW in Cambodia published since 1999. From each of the returned citations we subsequently studied reference lists to find additional data sources. We also searched websites for reports commissioned by national and international governmental and non-governmental organizations. RESULTS: Twenty-seven relevant studies and papers were found and reviewed; most were epidemiological in nature. Recent epidemiological studies and reports show an increase in HIV prevalence among Cambodian MSM and TGW. The epidemiology of HIV infection in these groups has been relatively well-described and analyzed. While initially MSM and TGW were grouped together, in more recent years they have been studied in their own right, recognizing their specific HIV and other prevention needs. Few studies were found investigating Cambodian same-sex cultures and social and cultural contexts in which HIV transmission among MSM and TGW occurs. A few evaluation studies were found, but it remains unknown how effective current HIV service implementation modalities are, or how successful strategies to increase access to essential HIV prevention, testing and treatment services have been employed for MSM and TGW in Cambodia. CONCLUSIONS: Research about Cambodian MSM and TGW in the context of HIV primarily concerns bio-behavioral knowledge generation. Cambodia is unlikely to achieve control of the HIV epidemic among MSM and TGW without doing better in-depth social science research on its multiple sexual- and gender minority cultures, and without understanding what differentiated implementation modalities, strategies and approaches are most effective to address HIV among its increasingly diverse MSM and TGW populations.

Uptake of Primary Care Services and HIV and Syphilis Infection among Transgender Women attending the Tangerine Community Health Clinic, Bangkok, Thailand, 2016 - 2019.

INTRODUCTION: Transgender women (TGW) need a specific package of primary care services usually not available in the publicly funded healthcare system. In addition, little is known about HIV and syphilis prevalence and incidence in clinic-based samples of TGW. Here we evaluate the uptake of a transgender-specific package of primary care services by TGW in Bangkok, Thailand and assess HIV and syphilis prevalence and incidence among them. METHODS: Open cohort study of TGW attending services at the Tangerine Community Health Clinic from 2016 to 2019. Cross-sectional and longitudinal analysis of routinely collected clinic data was performed to study trends in the number of clients, clinic visits and HIV and syphilis prevalence and incidence. RESULTS: During the study period, 2947 TGW clients made a total of 5227 visits to Tangerine. The number of clients significantly increased from 446 in 2016 to 1050 in 2019 (p < 0.001) and the number of visits from 616 to 2198 during the same period (p < 0.001). Prevalence of HIV at first visit was 10.8% and of syphilis 9.8%. HIV incidence was 1.03 per 100 person years (PY) and of syphilis 2.06 per 100 PY of follow-up. From 2016 to 2019, significant decreases occurred in the annual prevalence of HIV from 14.6% to 9.9% (p < 0.01). The annual prevalence of syphilis significantly increased from 6.6% in 2016 to 14.6% in 2018, and then decreased to 7.3% in 2019 (p < 0.001). The annual HIV incidence decreased during 2016 to 2019, from 1.68 to 1.28 per 100 PY, but this reduction was not statistically significant. The annual incidence of treponemal test seroconversion significantly increased from zero in 2016 to 4.55 per 100 PY in 2019 (p < 0.001). CONCLUSIONS: The increasing uptake of a transgender-specific package of services, including co-located gender affirmative hormone therapy, suggests this may be an effective model in engaging and retaining TGW in primary care. The decrease in HIV prevalence and low HIV incidence across calendar years point at a possible reduction of HIV acquisition among the TGW population served by Tangerine. The increasing prevalence of syphilis suggests ongoing high-risk sexual behaviour and underscores the need for screening and treatment for this infection at the time of delivery of HIV services.

Recent declines in HIV infections at Silom Community Clinic Bangkok, Thailand corresponding to HIV prevention scale up: An open cohort assessment 2005-2018.

OBJECTIVES: We assessed HIV-1 infection among men who have sex with men (MSM) attending Silom Community Clinic (SCC) in Bangkok, Thailand from 2005 to 2018. Since 2014, Thailand increased implementation of HIV prevention strategies including pre-exposure prophylaxis and Treatment as Prevention. METHODS: MSM attending SCC were tested for HIV using rapid tests. We assessed trends in HIV prevalence, incidence and compared incidence before and after 2014. RESULTS: From 2005 to 2018, 14,034 clients attended SCC for HIV testing. The HIV prevalence increased from 19.2% in 2005-2006 to 34-0% in 2010, remained stable until 2016 and decreased to 17.2% in 2018 (p<0.0001). The HIV incidence was 4.1 per 100 person-years (PY), with an inverted U-shape trend and a peak in 2009 (p<0.0001). Incidence among young MSM aged 13-21 years remained high at 10.0 per 100 PY. Among those aged 22-29 years, lower incidence was found from Q 3 2016, with a relative risk reduction of 46.2% (p<0.001); and a similar reduction among those aged ≥30 years from Q4 2014, corresponding to scale up of HIV prevention strategies. CONCLUSION: We found a decline in HIV infection among Thai MSM. However, incidence remained high among young MSM.

The epidemiology of human immunodeficiency virus infection, sexually transmitted infections, and associated risk behaviors among men who have sex with men in the Mekong Subregion and China: implications for policy and programming.

BACKGROUND: Little systematic knowledge is available regarding risk behaviors and the prevalence of human immunodeficiency virus (HIV) and sexually transmitted infections (STI) in populations of men having sex with men (MSM) in the Mekong Subregion and China. METHODS: Data on HIV/STI prevalence and risk behavior of MSM in the region were collected through Internet searches, were summarized and assessed for their policy and programming implications. RESULTS: Twenty-four articles, reports and abstracts of research studies were identified for review. High levels of HIV, STI and associated risk behavior were reported among MSM throughout the region. The HIV prevalence among MSM in urban areas varied between 5.5% and 28.3% in Thailand and Cambodia and between 0.0% and 9.4% in Vietnam and China. No HIV/STI prevalence data were available for Lao PDR and Myanmar. CONCLUSION: Levels of HIV/STI prevalence and risk behavior among MSM in the Mekong Subregion and China are high. Continued monitoring and surveillance and targeted preventive interventions are necessary to stop the spread of HIV in this vulnerable population.