HIV and syphilis prevalence among transgender women and men who have sex with men, Silom Community Clinic, Bangkok, Thailand, 2017-2019

We assessed HIV and syphilis infection among MSM and TGW attending Silom Community Clinic from 2017 to 2019. Walk-in and referral clients completed a registration application including a question on gender identity. We compared the prevalence of HIV, syphilis, and HIV and syphilis coinfection among TGW and MSM. In a total of 1050 clients, 276 (26.3%) were TGW and 774 (74.7%) were MSM. Among TGW clients, HIV prevalence was 29.8%, syphilis prevalence was 38.4%, and coinfection prevalence was 18.5%. Comparing prevalence among TGW to MSM, the adjusted prevalence ratio (aPR) for HIV was 1.8 (95% CI:1.4-2.3), for syphilis was 1.2 (95% CI:1.0-1.4), and for HIV and syphilis coinfection was 2.1 (95% CI:1.4-2.9). The prevalence of syphilis was higher than HIV among TGW, with a PR of 1.3 (95% CI:1.1-1.6), and among MSM, with a PR of 1.4 (95% CI:1.2-1.7). TGW age 15-21 years had an HIV prevalence of 16.9% and syphilis prevalence of 30.8%. After adjusting for age, referral, and sexual behaviors, TGW remain significantly associated with HIV and syphilis prevalence. There is a substantial burden of HIV and HIV/syphilis co-infection among TGW. HIV/STI prevention are needed for TGW, including linkage to HIV care.

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.

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.

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.

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.

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.

HIV Incidence and Risk Behaviours of People Who Inject Drugs in Bangkok, 1995-2012

BACKGROUND

Three consecutive prospective studies were conducted among people who inject drugs (PWID) from May 1995 through June 2012 in Bangkok, Thailand. We examined data from these studies to evaluate HIV incidence and explore trends in risk behaviours.

METHODS

We used data from a 1995-1998 cohort study, a 1999-2004 HIV vaccine trial, and a 2005-2012 HIV pre-exposure prophylaxis (PrEP) study to examine per-quarter trends in HIV incidence, using a restricted cubic spline function for time in a Poisson regression. We also examined temporal trends in HIV-associated risk behaviours.

FINDINGS

HIV incidence declined from 5.7 per 100 person-years during the cohort study, to 2.7 per 100 person-years in the vaccine trial, to 0.7 per 100 person-years among PrEP study placebo recipients. Incidence peaked at 12.1 per 100 person-years in 1996 and declined to < 1 per 100 person-years during 2005-2012. Reports of injecting drugs and sharing needles also declined from the cohort study to the PrEP study (p < 0.0001). Heroin was the most common drug injected during the cohort study and the vaccine trial, but stimulants (e.g., methamphetamine) and sedatives (e.g., midazolam) were injected more often during the PrEP study.

INTERPRETATION

HIV incidence among PWID declined during 2005-2012. Several factors likely contributed to the decline, including decreases in the frequency of injecting and sharing, improved access to HIV testing and antiretroviral therapy, and the use of PrEP. Expanding access to effective HIV prevention tools can hasten control of the HIV epidemic among PWID.

FUNDING

The Bangkok Metropolitan Administration and U.S. Centers for Disease Control and Prevention, Division of HIV/AIDS Prevention.

Estimating recent HIV incidence among young men who have sex with men: Reinvigorating, validating and implementing Osmond's algorithm for behavioral imputation

HIV incidence information is essential for epidemic monitoring and evaluating preventive interventions. However, reliable HIV incidence data is difficult to obtain, especially among marginalized populations, such as young men who have sex with men (YMSM). Here we evaluate the reliability of an alternative HIV incidence assessment method, behavioral imputation, as compared to serologically estimated HIV incidence. Recent HIV incidence among YMSM (aged 18 to 21 and 18 to 24 years) enrolled in a cohort study in Bangkok from 2006 to 2014 was estimated using two mid-point methods for seroconversion: 1) between age of first anal intercourse and first HIV-positive test (without previous HIV-negative test) (behavioral imputation) and 2) between the date of last negative and first positive HIV test (serological estimation). Serologically estimated HIV incidence was taken as the "gold standard" to evaluate between-method agreement. At baseline, 314 YMSM age 18 to 21 years accumulated 674 person-years (PY) of follow-up since first anal intercourse. Considering that 50 men had prevalent HIV infection, the behaviorally imputed HIV incidence was 7.4 per 100 PY. Of the remaining 264 HIV-negative men, 54 seroconverted for HIV infection during the study, accumulating 724 PY of follow-up and a serologically estimated HIV incidence of 7.5 per 100 PY. At baseline, 712 YMSM age 18 to 24 years (including 18 to 21-year-old men analyzed above) accumulated 2143 PY of follow-up since first anal intercourse. Considering that 151 men had prevalent HIV infection, the behaviorally imputed HIV incidence was 7.0 per 100 PY. Of the remaining 561 HIV-negative men, 125 seroconverted for HIV infection during the study, accumulating 1700 PY of follow-up and a serologically estimated HIV incidence of 7.4 per 100 PY. Behavioral imputation and serological estimation are in good agreement when estimating recent HIV incidence in YMSM.

"I am not promiscuous enough!": Exploring the low uptake of HIV testing by gay men and other men who have sex with men in Metro Manila, Philippines

The Philippines faces a severe HIV epidemic among gay and other men who have sex with men (MSM). HIV testing uptake remains low. A case series of 12 men from Metro Manila were interviewed to explore barriers to uptake of HIV testing services. Most did not see the need to get tested for HIV despite significant risk, based on the misconception they were feeling well or showed no symptoms. Being of a higher socioeconomic class, feeling morally superior to other gay men, distance of the testing facility, fear of what will happen once infected, fear of HIV- and sexual stigma, fear of side effects of antiretroviral drugs and fear of high health care expenses after testing positive for HIV were key reasons why MSM kept postponing their test. Misconceptions about HIV risk, disease, and treatment and care need to be addressed in order to increase uptake of HIV services in this population.

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.

PrEP implementation in the Asia-Pacific region: opportunities, implementation and barriers

INTRODUCTION

HIV epidemics in the Asia-Pacific region are concentrated among men who have sex with men (MSM) and other key populations. Pre-exposure prophylaxis (PrEP) is an effective HIV prevention intervention and could be a potential game changer in the region. We discuss the progress towards PrEP implementation in the Asia-Pacific region, including opportunities and barriers.

DISCUSSION

Awareness about PrEP in the Asia-Pacific is still low and so are its levels of use. A high proportion of MSM who are aware of PrEP are willing to use it. Key PrEP implementation barriers include poor knowledge about PrEP, limited access to PrEP, weak or non-existent HIV prevention programmes for MSM and other key populations, high cost of PrEP, stigma and discrimination against key populations and restrictive laws in some countries. Only several clinical trials, demonstration projects and a few larger-scale implementation studies have been implemented so far in Thailand and Australia. However, novel approaches to PrEP implementation have emerged: researcher-, facility- and community-led models of care, with PrEP services for fee and for free. The WHO consolidated guidelines on HIV testing, treatment and prevention call for an expanded access to PrEP worldwide and have provided guidance on PrEP implementation in the region. Some countries like Australia have released national PrEP guidelines. There are growing community leadership and consultation processes to initiate PrEP implementation in Asia and the Pacific.

CONCLUSIONS

Countries of the Asia-Pacific region will benefit from adding PrEP to their HIV prevention packages, but for many this is a critical step that requires resourcing. Having an impact on the HIV epidemic requires investment. The next years should see the region transitioning from limited PrEP implementation projects to growing access to PrEP and expansion of HIV prevention programmes.

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.

HIV pre-exposure prophylaxis and health and community systems in the Global South: Thailand case study

INTRODUCTION

Pre-exposure prophylaxis (PrEP) is recommended by the World Health Organization as an effective method of HIV prevention for individuals at risk for infection. In this paper, we describe the unique role that Thailand has played in the global effort to combat the HIV epidemic, including its role in proving the efficacy of PrEP, and discuss the opportunities and challenges of implementing PrEP in a middle-income country.

DISCUSSION

Thailand was one of the first countries in the world to successfully reverse a generalized HIV epidemic. Despite this early success, HIV prevalence has remained high among people who inject drugs and has surged among men who have sex with men (MSM) and transgender women (TGW). Two pivotal trials that showed that the use of oral antiretroviral medication as PrEP can reduce HIV transmission were conducted partially or entirely at Thai sites. Demonstration projects of PrEP, as well as clinical trials of alternative PrEP regimens, began or will begin in 2014-2015 in Thailand and will provide additional data and experience on how to best implement PrEP for high-risk individuals in the community. Financing of drug costs, the need for routine laboratory monitoring and lack of awareness about PrEP among at-risk groups all present challenges to the wider implementation of PrEP for HIV prevention in Thailand.

CONCLUSIONS

Although significant challenges to wider use remain, PrEP holds promise as a safe and highly effective method to be used as part of a combined HIV prevention strategy for MSM and TGW in Thailand.

Scaling up of HIV treatment for men who have sex with men in Bangkok: a modelling and costing study

BACKGROUND

Despite the high prevalence of HIV in men who have sex with men (MSM) in Bangkok, little investment in HIV prevention for MSM has been made. HIV testing and treatment coverage remains low. Through a pragmatic programme-planning approach, we assess possible service linkage and provision of HIV testing and antiretroviral treatment (ART) to MSM in Bangkok, and the most cost-effective scale-up strategy.

METHODS

We obtained epidemiological and service capacity data from the Thai National Health Security Office database for 2011. We surveyed 13 representative medical facilities for detailed operational costs of HIV-related services for sexually active MSM (defined as having sex with men in the past 12 months) in metropolitan Bangkok. We estimated the costs of various ART scale-up scenarios, accounting for geographical accessibility across Bangkok. We used an HIV transmission population-based model to assess the cost-effectiveness of the scenarios.

FINDINGS

For present HIV testing (23% [95% CI 17-36] of MSM at high risk in 2011) and ART provision (20% of treatment-eligible MSM at high risk on ART in 2011) to be sustained, a US$73·8 million ($51·0 million to $97·0 million) investment during the next decade would be needed, which would link an extra 43,000 (27,900-58,000) MSM at high risk to HIV testing and 5100 (3500-6700) to ART, achieving an ART coverage of 44% for MSM at high risk in 2022. An additional $55·3 million investment would link an extra 46,700 (30,300-63,200) MSM to HIV testing and 12,600 (8800-16,600) to ART, achieving universal ART coverage of this population by 2022. This increased investment is achievable within present infrastructure capacity. Consequently, an estimated 5100 (3600-6700) HIV-related deaths and 3700 (2600-4900) new infections could be averted in MSM by 2022, corresponding to a 53% reduction in deaths and a 35% reduction in infections from 2012 levels. The expansion would cost an estimated $10,809 (9071-13,274) for each HIV-related death, $14,783 (12,389-17,960) per new infection averted, and $351 (290-424) per disability-adjusted life-year averted.

INTERPRETATION

Spare capacity in Bangkok's medical facilities can be used to expand ART access for MSM with large epidemiological benefits. The expansion needs increased funding directed to MSM services, but given the epidemiological trends, is probably cost effective. Our modelling approach and outcomes are likely to be applicable to other settings.

FUNDING

World Bank Group and Australian National Health and Medical Research Council.

Temporal trends in HIV-1 incidence and risk behaviours in men who have sex with men in Bangkok, Thailand, 2006-13: an observational study

BACKGROUND

HIV-1 incidence in men who have sex with men (MSM) is often difficult to estimate. We therefore assessed temporal trends in HIV-1 incidence and behavioural risk factors in MSM in Bangkok, Thailand, from 2006 to 2013.

METHODS

In this observational study, we used data for clients attending the Silom Community Clinic for voluntary counselling and testing (VCT) services and from the Bangkok MSM Cohort Study (BMCS) to investigate trends in HIV incidence per 100 person-years per quarter in both cohorts. During VCT, basic demographic data were gathered at registration. However, no behavioural risk data were gathered. In the BMCS, we gathered demographic and behavioural data at baseline and at regular study visits using audio computer-assisted self-interviewing. Questions were included about potential risk factors such as drug use, sexual practices, and how often condoms were used. We also analysed behavioural risk factors in the BMCS cohort, using a restricted cubic spline function for time.

FINDINGS

From 2006 to 2013, 8176 MSM came for VCT; 1999 (24%) clients were initially seronegative and returned for another test. 235 (12%) individuals seroconverted. The overall HIV-1 incidence was 5.5 per 100 person-years (95% CI 4.8-6.3), with an increasing trend (adjusted p=0.02). In the BMCS, 1372 people were seronegative at baseline; 1259 (92%) had more than one follow-up test and 238 (17%) seroconverted. The overall HIV-1 incidence was 5.3 per 100 person-years (95% CI 4.7-6.1), with an increase and then a decline (inverted U-shaped curve, p=0.0001). Individuals aged 21 years and younger were at significantly higher risk of HIV infection than were those aged 30 years and older in the in the VCT (rate ratio 2.29, 95% CI 1.88-2.78, p<0.0001) and BMCS cohorts (1.99, 1.50-2.65, p<0.0001). Overall, drug use (p=0.03), drug use to enhance sex (p=0.0006), use of drugs for erectile dysfunction (p<0.0001), and 100% condom use (p<0.0001) increased over time, whereas the proportion of individuals reporting receptive anal intercourse decreased (p=0.004).

INTERPRETATION

With a sustained high HIV-1 incidence and increasing drug use in MSM in Bangkok, we urgently need innovative and acceptable HIV prevention interventions, especially for young MSM.

FUNDING

US Centers for Disease Control and Prevention.

Biomedical HIV prevention research and epidemic control in Thailand: two sides of the same coin

For a country with a moderate adult HIV prevalence of just over 1% in 2012, Thailand is widely perceived as having made some extraordinary contributions to the global management of the HIV/AIDS pandemic. It has been promoted as a model of effective HIV control and applauded for its leadership in providing access to antiretroviral treatment. Thailand has also received international recognition for its contribution to biomedical HIV prevention research, which is generally perceived as exceptional. In this paper, Thailand's global role model function as an example of effective HIV/AIDS control and high-quality biomedical HIV prevention research is re-evaluated against the background of currently available data and more recent insights. The results indicate that Thailand's initial response in raising the level of the political significance of HIV/AIDS was indeed extraordinary, which probably prevented a much larger epidemic from occurring. However, this response transpired in unusual extraconstitutional circumstances and its effectiveness declined once the country returned to political normalcy. Available data confirm the country's more than exceptional contribution to biomedical HIV prevention research. Thailand has made a huge contribution to the global management and control of the HIV/AIDS pandemic.

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.

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.

Knowledge of and interest in using preexposure prophylaxis for HIV prevention among men who have sex with men in Thailand

Little is known about HIV preexposure prophylaxis (PrEP) acceptability among men who have sex with men (MSM) in Thailand. The authors recruited an online convenience sample of Thai MSM (n = 404) to assess the knowledge of and interest in PrEP. Less than 7% had heard of PrEP; however, 35% indicated interest in PrEP after an explanation of its possible efficacy. Regression modeling demonstrated that HIV knowledge and risk behavior, but not demographics, are significant predictors of PrEP interest. More information and education about PrEP is necessary and more research is needed to examine PrEP acceptability and to inform the message for PrEP uptake.

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.

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.

Impact of multi-targeted antiretroviral treatment on gut T cell depletion and HIV reservoir seeding during acute HIV infection

BACKGROUND

Limited knowledge exists on early HIV events that may inform preventive and therapeutic strategies. This study aims to characterize the earliest immunologic and virologic HIV events following infection and investigates the usage of a novel therapeutic strategy.

METHODS AND FINDINGS

We prospectively screened 24,430 subjects in Bangkok and identified 40 AHI individuals. Thirty Thais were enrolled (8 Fiebig I, 5 Fiebig II, 15 Fiebig III, 2 Fiebig IV) of whom 15 completed 24 weeks of megaHAART (tenofovir/emtricitabine/efavirenz/raltegravir/maraviroc). Sigmoid biopsies were completed in 24/30 at baseline and 13/15 at week 24. At baseline, the median age was 29 years and 83% were MSM. Most were symptomatic (87%), and were infected with R5-tropic (77%) CRF01_AE (70%). Median CD4 was 406 cells/mm(3). HIV RNA was 5.5 log(10) copies/ml. Median total blood HIV DNA was higher in Fiebig III (550 copy/10(6) PBMC) vs. Fiebig I (8 copy/10(6) PBMC) (p = 0.01) while the median %CD4+CCR5+ gut T cells was lower in Fiebig III (19%) vs. Fiebig I (59%) (p = 0.0008). After 24 weeks of megaHAART, HIV RNA levels of <50 copies were achieved in 14/15 in blood and 13/13 in gut. Total blood HIV DNA at week 0 predicted reservoir size at week 24 (p<0.001). Total HIV DNA declined significantly and was undetectable in 3 of 15 in blood and 3 of 7 in gut. Frequency of CD4+CCR5+ gut T cells increased from 41% at baseline to 64% at week 24 (p>0.050); subjects with less than 40% at baseline had a significant increase in CD4+CCR5+ T cells from baseline to week 24 (14% vs. 71%, p = 0.02).

CONCLUSIONS

Gut T cell depletion and HIV reservoir seeding increases with progression of AHI. MegaHAART was associated with immune restoration and reduced reservoir size. Our findings could inform research on strategies to achieve HIV drug-free remission.

Enrollment characteristics and risk behaviors of injection drug users participating in the Bangkok Tenofovir Study, Thailand

Background

The Bangkok Tenofovir Study was launched in 2005 to determine if pre-exposure prophylaxis with tenofovir will reduce the risk of HIV infection among injecting drug users (IDUs). We describe recruitment, screening, enrollment, and baseline characteristics of study participants and contrast risk behavior of Tenofovir Study participants with participants in the 1999–2003 AIDSVAX B/E Vaccine Trial.

Methods

The Bangkok Tenofovir Study is an ongoing, phase-3, randomized, double-blind, placebo-controlled, HIV pre-exposure prophylaxis trial of daily oral tenofovir. The Tenofovir Study and the Vaccine Trial were conducted among IDUs at 17 drug-treatment clinics in Bangkok. Tenofovir Study sample size was based on HIV incidence in the Vaccine Trial. Standardized questionnaires were used to collect demographic, risk behavior, and incarceration data. The Tenofovir Study is registered with ClinicalTrials.gov, number-NCT00119106.

Results

From June 2005 through July 2010, 4094 IDUs were screened and 2413 enrolled in the Bangkok Tenofovir Study. The median age of enrolled participants was 31 years (range, 20–59), 80% were male, and 63% reported they injected drugs during the 3 months before enrollment. Among those who injected, 53% injected methamphetamine, 37% midazolam, and 35% heroin. Tenofovir Study participants were less likely to inject drugs, inject daily, or share needles (all, p<0.001) than Vaccine Trial participants.

Discussion

The Bangkok Tenofovir Study has been successfully launched and is fully enrolled. Study participants are significantly less likely to report injecting drugs and sharing needles than participants in the 1999–2003 AIDSVAX B/E Vaccine Trial suggesting HIV incidence will be lower than expected. In response, the Bangkok Tenofovir Study enrollment was increased from 1600 to 2400 and the study design was changed from a defined 1-year follow-up period to an endpoint-driven design. Trial results demonstrating whether or not daily oral tenofovir reduces the risk of HIV infection among IDUs are expected in 2012.

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.

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.

Examining HIV infection among male sex workers in Bangkok, Thailand: a comparison of participants recruited at entertainment and street venues

HIV prevalence and associated factors were examined among male sex workers (MSWs, N = 414) in Bangkok, Thailand. Cross-sectional venue-day-time sampling was used to collect data in entertainment and street venues. Chi-square and logistic regression were used to identify HIV risk factors. HIV prevalence was 18.8% overall, but differences were found between MSW recruited in entertainment and street venues. Significant relationships were found between several demographic, behavioral, exposure to HIV prevention, and other characteristics, and recruitment location. In multivariate analyses, being sexually attracted to men was significantly associated with HIV infection among both groups of sex workers. In addition, among street-based sex workers, not having had sex with a woman in the past 3 months, having ever had a sexually transmitted disease symptom, and not having a friend to talk to about personal problems were significantly associated with HIV infection.

Sex frequency and sex planning among men who have sex with men in Bangkok, Thailand: implications for pre- and post-exposure prophylaxis against HIV infection

Background

Daily HIV antiretroviral pre-exposure prophylaxis (PrEP) is being evaluated in clinical trials among men who have sex with men (MSM). However, daily PrEP may not be congruent with sexual exposure profiles of MSM. Here, we investigate sex frequency and sex planning to identify and inform appropriate PrEP strategies for MSM.

Methods

We evaluated sex frequency and sex planning in a cohort of HIV-negative MSM in Bangkok, Thailand. Chi-squared test was used to compare reports of sex on different weekdays; logistic regression was used to identify predictors of sex frequency and sex planning.

Results

Of 823 MSM (with a mean age of 28.3 years), 86% reported having sex on two days per week or less, and 65% reported their last sex to have been planned. Sex on the weekend (~30%) was more often reported than sex on weekdays (~23%). In multivariate analysis, use of alcohol, erectile dysfunction drugs, group sex, sex with a foreigner, buying and selling sex, and a history of HIV testing were associated with having sex on three days or more per week. Being aged 22 to 29 years, not identifying as homosexual, having receptive anal intercourse, and not engaging in group sex were associated with unplanned sex.

Conclusions

Intermittently dosed PrEP (as opposed to daily) may be a feasible HIV prevention strategy and should be considered for evaluation in clinical trials. Risk factors for sex frequency and sex planning may help to identify those in need for daily PrEP and those who may not be able to take a timely pre-exposure dose.

Inconsistent condom use among young men who have sex with men, male sex workers, and transgenders in Thailand

Young men who have sex with men (MSM) are at risk for HIV infection. We investigated inconsistent condom use among 827 sexually active young MSM (15-24 years), enrolled using venue-day-time sampling in Bangkok, Chiang Mai and Phuket, Thailand. Data was collected using palmtop computer-assisted self-interviewing. Of participants, 33.1% were regular MSM, 37.7% were male sex workers (MSWs) and 29.1% were transgenders (TGs). Of MSM, 46.7%, of MSWs, 34.9% and of TGs, 52.3% reported recent inconsistent condom use. In multivariate analysis, receptive anal intercourse (MSM, MSWs), receptive and insertive anal intercourse, living alone and a history of sexual coercion (MSWs), not carrying a condom when interviewed (MSM, TGs), lower education, worrying about HIV infection and a history of sexually transmitted infections (TGs) were significantly and independently associated with inconsistent condom use. Interventions for young MSM are needed and must consider the distinct risk factors of MSM, MSWs, and TGs.

Sexual behavior and risk factors for HIV infection among homosexual and bisexual men in Thailand

HIV prevalence and associated risk behaviors were examined among Thai bisexually active men (MSMW, n = 450) and men who have sex with men only (MSM-only, n = 1,125). Cross sectional venue-day-time sampling was used to collect data. Chi-square and logistic regression were used to identify HIV risk factors. HIV prevalence was 8.2% among MSMW and 21.2% among MSM-only. Consistent condom use with male partners was higher among MSMW (77.6%) than MSM-only (62.9%), and lower with female partners (44.4%). Lack of family confidant, migration, concern about acquiring HIV infection, and self-reported STD were associated with HIV prevalence among MSMW. Older age, lower educational level, residing in Bangkok or Chiang Mai, living away from family, recruitment from a sauna, increased frequency of visiting the surveyed venue, practicing receptive or both receptive and insertive anal intercourse, inconsistent condom use with male paying partners, and a history of drug use were associated with HIV prevalence in MSM-only.

Factors associated with incarceration and incident human immunodeficiency virus (HIV) infection among injection drug users participating in an HIV vaccine trial in Bangkok, Thailand, 1999-2003

AIMS

To determine if incarceration was associated with human immunodeficiency virus (HIV) infection and identify risk factors for incarceration among injection drug users (IDUs) participating in an HIV vaccine trial in Bangkok.

DESIGN

The AIDSVAX B/E HIV vaccine trial was a randomized, double-blind, placebo-controlled study. A proportional hazards model was used to evaluate demographic characteristics, risk behavior and incarceration as predictors of HIV infection and generalized estimation equation logistic regression analysis to investigate demographic characteristics and risk behaviors for predictors of incarceration.

SETTING

The trial was conducted in Bangkok Metropolitan Administration drug-treatment clinics, 1999-2003.

PARTICIPANTS

A total of 2546 HIV-uninfected IDUs enrolled in the trial.

MEASUREMENTS

HIV testing was performed and an interviewer-administered questionnaire was used to assess risk behavior and incarceration at baseline and every 6 months for a total of 36 months.

FINDINGS

HIV incidence was 3.4 per 100 person-years [95% confidence interval (CI), 3.0-3.9] and did not differ among vaccine and placebo recipients. In multivariable analysis, being in jail (P < 0.04), injecting (P < 0.0001), injecting daily (P < 0.0001) and sharing needles (P = 0.02) were associated with HIV infection and methadone maintenance was protective (P = 0.0006). Predictors of incarceration in multivariable analysis included: male sex (P = 0.04), younger age (P < 0.0001), less education (P = 0.001) and being in jail (P < 0.0001) or prison (P < 0.0001) before enrollment.

CONCLUSIONS

Among IDUs in the AIDSVAX B/E trial, incarceration in jail was associated with incident HIV infection. IDUs in Thailand remain at high risk of HIV infection and additional prevention tools are needed urgently. HIV prevention services, including methadone, should be made available to IDUs.

Social harms in injecting drug users participating in the first phase III HIV vaccine trial in Thailand

OBJECTIVE

To study related social harms due to identification with a group of participants in an HIV-1 vaccine trial who are potentially high risk for HIV/AIDS.

MATERIAL AND METHOD

Two thousand five hundred forty six injecting drug users (IDU) were enrolled in a 36-month vaccine trial. Volunteers received education and risk reduction counseling at every six-month study visit. Social harms were not actively solicited, but volunteers were encouraged to report any during the process of counseling at every six-month visit. If a social harm was reported, a questionnaire was administered and the harm was tracked If necessary, clinic staff assisted in resolving the social harm.

RESULTS

Thirty-nine social harms were reported by 37 participants; 33 (84.6%) were disturbances in personal relationships, three (7.7%) in employment, one (2.6%) was medically related, one (2.6%) was related to admission in the military and one (2.6%) was related with misbelieve about the vaccine. The most common reason for disturbances in personal relationships was suspicion of HIV infection (n=20). The impact of these harms on quality of life was characterized as minimal by 31 (79.5%) participants, as moderate by seven (17.9%), and as major by one (2.6%). All social harms were documented to be resolved by the end of the study.

CONCLUSION

A few participants reported study-related social harms during the course of the trial. Most harm had minimal impact and all could be resolved by the end of the present study.

Respondent-driven sampling to assess characteristics and estimate the number of injection drug users in Bangkok, Thailand

BACKGROUND

Since early in Thailand's HIV epidemic, HIV seroprevalence among injection drug users (IDUs) in Bangkok has been around 40%. As Thailand moves to strengthen HIV prevention and care programs for Bangkok IDUs, information on current patterns of drug use and an estimate of the size and composition of the IDU population are essential.

METHODS

We used respondent-driven sampling (RDS) to recruit Bangkok IDUs who reported injecting in the past 6 months. IDUs were interviewed with a standardized questionnaire. Logistic regression was used to compare IDUs currently or previously in treatment with those never treated. RDS software was used to estimate IDU population size based on the proportion in treatment.

RESULTS

Of 963 IDUs recruited, 828 (86%) were men. One hundred and twelve IDUs (12%) reported never having attended a drug treatment clinic. Young age, unemployment, injection of single drug, and never having been HIV tested were significantly associated with never-in-treatment status. The estimated proportion of IDUs in treatment was 0.55 (95% confidence interval, 0.52-0.60). Dividing the known number of IDUs in treatment (1981 IDUs attending Bangkok drug treatment clinics during October 2003 through March 2004) by this proportion, we estimated the number of IDUs in Bangkok during the period of RDS to be 3595 (95% confidence interval, 3296-3810).

CONCLUSIONS

Data obtained through RDS, although subject to limitations from co-existing government drug control policies and possible under-recruitment of out-of-treatment IDUs, will be useful in informing policy, strengthening prevention approaches, and improving methods to monitor the HIV epidemic among Thai IDUs.

The spread of HIV-1 subtypes B and CRF01_AE among injecting drug users in Bangkok, Thailand

The HIV epidemic among injecting drug users (IDUs) in Bangkok was initially dominated by HIV subtype B and later by the recombinant CRF01_AE. The present study investigates the distribution of the 2 variants in time and how it is affected by changes in injecting risk behavior and treatment. A mathematic model describing the spread of HIV subtype B and CRF01_AE among IDUs was developed, and data from the AIDSVAX B/E cohort of IDUs in Bangkok were used. From the model, it was calculated that during 1999 to 2003, the annual incidence of HIV was around 0.6 and 2.7 to 3.9 infections per 100 person-years for subtype B and CRF01_AE, respectively. Of the new infections, 18% and 72% are first infections with subtype B and CRF01_AE, respectively, and 9% are superinfections. With increases in risk behavior, the fraction of superinfections rises. If treatment reduces the infectivity of CRF01_AE more than that of subtype B, the fraction of subtype B infections should increase. Subtype B should remain prevalent in a small but considerable fraction of the population for a long time. Changes in risk behavior and the introduction of treatment may alter the distribution of subtypes, but CRF01_AE should remain dominant.

HIV communication between husbands and wives: effects on husband HIV testing in northern Thailand

In northern Thailand, where substantial male-to-female transmission of HIV has occurred in stable partnerships, the relationships between counseling, communication, and HIV-preventive behaviors in married couples have not been well studied. In a study of HIV incidence among women in northern Thailand, each participant was advised to learn her husband's HIV-infection status and was asked to bring him for an interview at the final 12-month follow-up visit. Of the 337 men interviewed, 58% reported having ever had an HIV test. More men reported testing following their wives' enrollment: 12% in the year prior to enrollment vs 22% during the 1-year study (p < 0.001). In the univariate analysis, men's HIV testing during the 6 months before being interviewed was associated with communication about HIV testing with their wife and extra marital sex with non-FSW while married. Testing following their wife's request was the most common reason reported. Agreement between husband's and wife's reports was poor for most issues, such as whether HIV-related communication had occurred, but agreement as to whether the husband had ever been tested for HIV was relatively high (kappa = 0.62). However, in the logistic regression analysis, only sex with non-FSW while married remained associated with HIV testing (p = 0.02). The results suggest a relationship between counseling, communication, and husband HIV testing. Better communication by couples may result in more effective use of HIV testing, which is already prevalent in this population, to prevent HIV transmission.

Inconsistent condom use with steady and casual partners and associated factors among sexually-active men who have sex with men in Bangkok, Thailand

HIV/STD risk behavior has not been examined in community samples of men who have sex with men (MSM) in Thailand. The sexually-active sample (n=927) was recruited from bars, saunas, and parks; 20% identified as bisexual and 17% tested HIV-positive. Inconsistent (<100%) condom use was reported by 45% of those with steady partners and 21% of those with casual partners in the prior three months. 21% had heard of effective HIV treatments (n=194), among whom 44% believed HIV was less serious and 36% said their risk behavior had increased after hearing about the treatments. In multivariate analysis, HIV-positive status, gay-identification, getting most HIV information from the radio, believing HIV can be transmitted by mosquito bite, and concern about acquiring an STD were associated with inconsistent condom use during anal sex; slightly older age (25-29 vs. 18-24 years) was associated with more consistent condom use. HIV/STD risk-reduction strategies for MSM in Bangkok should clearly state sexual risk to individuals in this population.

Sexual Initiation, Substance Use, and Sexual Behavior And Knowledge Among Vocational Students In Northern Thailand

CONTEXT

Thailand has undergone dramatic social changes in the last two decades, yet little is known about factors related to sexual initiation among adolescents.

METHODS

A survey using the audio computer-assisted self-interviewing method was conducted to assess social and demographic characteristics, substance use, sexual behavior, and knowledge of HIV and STIs among 1,725 vocational school students aged 15-21 living in northern Thailand. Gender differences for these factors were evaluated using chi-square and Mann-Whitney U tests. Multivariate survival analysis using Cox proportional hazards models assessed associations between these variables and sexual initiation for each gender.

RESULTS

Males initiated sexual intercourse at an earlier age than females (median ages of 17 and 18, respectively). At any given age, sexual initiation was associated with having a nonagricultural background and using alcohol or methamphetamine (adjusted rate ratios, 1.3-2.9). For males, initiation was also associated with having parents who did not live together, having a friend as a confidant, tobacco use, high perceived risk for HIV and high STI knowledge (1.3-1.7). For females, other factors associated with earlier initiation were younger age at interview, living away from family, lacking a family member as a confidant, high perceived risk for STIs and ever having smoked marijuana (1.3-2.4).

CONCLUSIONS

Interventions to ameliorate the adverse consequences of early sexual initiation need to address social influences such as parents and peer groups. Programs should identify and target high-risk subgroups, such as those who are sexually experienced at an early age and those engaged in patterns of generalized risk-taking.

Symptoms of posttraumatic stress disorder and depression among children in tsunami-affected areas in southern Thailand

CONTEXT

On December 26, 2004, an undersea earthquake occurred off the northwestern coast of Sumatra, Indonesia. The tsunami that followed severely impacted all 6 southwestern provinces of Thailand, where approximately 20,000 children were directly affected.

OBJECTIVE

To assess trauma experiences and the prevalence of symptoms of posttraumatic stress disorder (PTSD) and depression among children in tsunami-affected provinces in southern Thailand.

DESIGN, SETTING, AND PARTICIPANTS

Population-based mental health surveys were conducted among children aged 7 to 14 years in Phang Nga, Phuket, and Krabi provinces from February 15-22, 2005 (2 months posttsunami), and September 7-12, 2005 (9 months posttsunami).

MAIN OUTCOME MEASURES

Trauma experiences and symptoms of PTSD and depression as measured by a tsunami-modified version of the PsySTART Rapid Triage System, the UCLA PTSD Reaction Index, and the Birleson Depression Self-Rating Scale.

RESULTS

A total of 371 children (167 displaced and living in camps, 99 not displaced from villages affected by the tsunami, and 105 not displaced from unaffected villages) participated in the first survey. The prevalence rates of PTSD symptoms were 13% among children living in camps, 11% among children from affected villages, and 6% among children from unaffected villages (camps vs unaffected villages, P = .25); for depression symptoms, the prevalence rates were 11%, 5%, and 8%, respectively (P = .39). In multivariate analysis of the first assessment, having had a delayed evacuation, having felt one's own or a family member's life to have been in danger, and having felt extreme panic or fear were significantly associated with PTSD symptoms. Older age and having felt that their own or a family member's life had been in danger were significantly associated with depression symptoms. In the follow-up survey, 72% (151/210) of children from Phang Nga participated. Prevalence rates of symptoms of PTSD and depression among these children did not decrease significantly over time.

CONCLUSIONS

This assessment documents the prevalence of mental health problems among children in tsunami-affected provinces in southern Thailand at 2 and 9 months posttsunami. Traumatic events experienced during the tsunami were significantly associated with symptoms of PTSD and depression. These data may be useful to target mental health services for children and may inform the design of these interventions.

Mental health problems among adults in tsunami-affected areas in southern Thailand

CONTEXT

On December 26, 2004, an undersea earthquake occurred off the northwestern coast of Sumatra, Indonesia. The tsunami that followed severely affected all 6 southwestern provinces of Thailand, where 5395 individuals died, 2991 were unaccounted for, and 8457 were injured.

OBJECTIVE

To assess the prevalence of symptoms of posttraumatic stress disorder (PTSD), anxiety, and depression among individuals residing in areas affected by the tsunami in southern Thailand as part of a public health emergency response and rapid assessment.

DESIGN, SETTING, AND PARTICIPANTS

A multistage, cluster, population-based mental health survey was conducted from February 15 to 22, 2005, of random samples of displaced (n = 371) and nondisplaced persons in Phang Nga province (n = 322) and nondisplaced persons in the provinces of Krabi and Phuket (n = 368). Data were collected using an interviewer-administered questionnaire on handheld computers. A surveillance follow-up survey of the displaced persons (n = 371) and nondisplaced persons (n = 322) in Phang Na was conducted in September 2005.

MAIN OUTCOMES MEASURES

Medical Outcomes Study-36 Short-Form Health Survey SF-36 to assess self-perceived general health, bodily pain, and social and emotional functioning; the Harvard Trauma Questionnaire to assess tsunami-specific traumatic events; and the Hopkins Checklist-25 to detect symptoms of anxiety and depression.

RESULTS

Participation rates for displaced and nondisplaced persons in the rapid assessment survey were 69% and 58%, respectively. Symptoms of PTSD were reported by 12% of displaced and 7% of nondisplaced persons in Phang Nga and 3% of nondisplaced persons in Krabi and Phuket. Anxiety symptoms were reported by 37% of displaced and 30% of nondisplaced persons in Phang Nga and 22% of nondisplaced persons in Krabi and Phuket. Symptoms of depression were reported by 30% of displaced and 21% of nondisplaced persons in Phang Nga and 10% of nondisplaced persons in Krabi and Phuket. In multivariate analysis, loss of livelihood was independently and significantly associated with symptoms of all 3 mental health outcomes (PTSD, anxiety, and depression). In the 9-month follow-up surveillance survey of 270 (73%) displaced and 250 (80%) nondisplaced participants in Phang Nga, prevalence rates of symptoms of PTSD, anxiety, and depression among displaced persons decreased to 7%, 24.8%, and 16.7%, respectively, and among nondisplaced persons, prevalence rates decreased to 2.3%, 25.9%, and 14.3%, respectively.

CONCLUSIONS

Among survivors of the tsunami in southern Thailand, elevated rates of symptoms of PTSD, anxiety, and depression were reported 8 weeks after the disaster, with higher rates for anxiety and depression than PTSD symptoms. Nine months after the disaster, the rates of those reporting these symptoms decreased but were still elevated. This information is important for directing, strengthening, and evaluating posttsunami mental health needs and interventions.

Palmtop-assisted self-interviewing for the collection of sensitive behavioral data: randomized trial with drug use urine testing

Palmtop-assisted self-interviewing (PASI) may provide a cheaper and more mobile alternative to audio-computer-assisted self-interviewing (ACASI) for collecting sensitive behavioral data. To evaluate PASI, in late 2002 the authors enrolled 1,283 Thai students aged 15-21 years in a randomized trial. Data collection used PASI, ACASI, self-administered questionnaire, and face-to-face interview in combination with drug-use urine testing. By use of reported levels of behaviors and agreement between self-reports of smoking and urine test results, PASI and ACASI (alpha = 0.05) were compared for noninferiority, and PASI and interview were compared for superiority (alpha = 0.05). Noninferiority of PASI was demonstrated by use of self-reports of the most sensitive areas of sexual behavior (e.g., oral sex, sexual intercourse, commercial sex, history of genital ulcers, pregnancy), as well as self-reports of less sensitive behaviors (e.g., alcohol use, dietary behaviors, symptoms of depression). Data generally showed noninferiority of PASI, ACASI, and self-administered questionnaires when compared with each other and superiority of PASI, ACASI, and self-administered questionnaires when compared with interviews. PASI agreements between self-reports of tobacco smoking and presence of nicotine metabolites in urine were noninferior to ACASI and superior to interviews. The establishment of PASI noninferiority and superiority using behavioral and biologic measures suggests that PASI is a scientifically acceptable alternative for collecting sensitive behavioral data.

Sexual risk reduction in a cohort of injecting drug users in Bangkok, Thailand

OBJECTIVE

Interventions to reduce sexual risk behavior among injecting drug users (IDUs) have generally had very modest effects, but almost all such interventions have been conducted within short time frames. This study assessed whether long-term participation in interventions to reduce sexual risk behavior was associated with reduced sexual risk behavior.

METHODS

A total of 806 IDUs participated in the Bangkok HIV Vaccine Trial Preparatory Cohort Study from 1995-1998 and remained in the study for at least 4 follow-up visits (approximately 16 months). Participants received HIV counseling and testing every 4 months and free condoms were provided. Structured interviews including questions on sexual behavior were administered every 4 months.

RESULTS

Approximately 40% of participants reported engaging in unprotected sex (vaginal intercourse without always using a condom) with a regular partner at each study visit, without any decline over time in this behavior. There were declines in the proportions of participants reporting unprotected sex with casual partners and with paid partners (men only) over time, but the declines were confined to the early period of the study. Unprotected sex with casual partners was associated with amphetamine use. Condom use increased substantially among participants who seroconverted for HIV during the study.

CONCLUSIONS

Interventions to reduce sexual risk behavior among HIV-seronegative IDUs over extended periods were no more likely to be effective than shorter interventions. New programs are needed to reduce sexual risk behavior among amphetamine users and among IDUs who are currently seronegative but are engaging in injection risk behaviors and in unprotected sex with regular partners.

CDC international HIV prevention research activities among injection drug users in Thailand and Russia

The Centers for Disease Control and Prevention (CDC) has participated in collaborative HIV prevention research activities in injection drug users (IDUs) with the Bangkok Metropolitan Administration (BMA) in Bangkok, Thailand, from 1995 to the present and with the Orel AIDS Center in Orel Oblast, Russia, from 2001 to 2003. Studies in Bangkok have included an HIV prevention trial preparatory cohort from 1995 to 1998, a seroconverter cohort from 1998 to the present, a phase III trial of the AIDSVAX B/E gp120 HIV vaccine from 1999 to 2003, and a phase II/III HIV prophylaxis trial with tenofovir scheduled to begin in 2005. Activities in Orel included a review of HIV surveillance data in 2001, focus group discussions and a case-control study with HIV-infected and -uninfected IDUs in 2001, a cross-sectional study with the female sex partners of male IDUs in 2002, and a community outreach intervention in 2002-2003. In Bangkok, 1,209 IDUs were enrolled in the preparatory cohort which revealed an HIV incidence of 5.8% per 100 person-years; 133 HIV-infected IDUs have been followed in the seroconverter cohort with >85% follow-up and HIV and tuberculosis care provided; 2,546 IDUs were enrolled in the HIV vaccine efficacy trial which was successfully completed with a follow-up rate of >95%, although the vaccine was not shown to be effective at reducing HIV incidence; and 1,600 IDUs will be enrolled in the daily tenofovir HIV prophylaxis trial in 2005. In Orel, initial focus group discussions and epidemiologic studies revealed low HIV knowledge and high rates of unsafe injecting and sexual practices among IDUs and their female sex partners; and educational campaigns and the community outreach intervention were developed and implemented. A steady decline in new HIV infections in IDUs was then observed in Orel in 2002-2003. CDC has participated in the conduct of successful collaborative HIV prevention research activities in Thailand and Russia over the past decade. The establishment of long-term relationships with in-country public health and community partners has been instrumental in the success of these efforts.