Neuropsychiatric and Laboratory Outcomes of Hepatitis C Treatment in an Early-Treated HIV Cohort in Thailand.

Background: Hepatitis C virus (HCV) coinfection may further compromise immunological and cognitive function in people with HIV (PWH). This study compared laboratory and neuropsychiatric measures across the periods of HCV seroconversion and direct-acting antiviral (DAA) therapy with sustained virologic response (SVR) among PWH who initiated antiretroviral therapy (ART) during acute HIV infection (AHI) and acquired HCV after 24 weeks of ART. Methods: Participants from the RV254 AHI cohort underwent paired laboratory and neuropsychiatric assessments during regular follow-up. The former included measurements of CD4 + and CD8 + T-cell counts, HIV RNA, liver enzymes, and lipid profiles. The latter included the Patient Health Questionnaire-9 (PHQ-9), Distress Thermometer (DT), and a 4-test cognitive battery that evaluated psychomotor speed, executive function, fine motor speed and dexterity. The raw scores in the battery were standardized and averaged to create an overall performance (NPZ-4) score. Parameters of HCV-coinfected participants were compared across HCV seroconversion and DAA treatment groups. Results: Between 2009 and 2022, 79 of 703 RV254 participants acquired HCV after ≥ 24 weeks of ART; 53 received DAA, and 50 (94%) achieved SVR. All participants were Thai males (median age: 30 years); 34 (68%) denied past intravenous drug use, and 41 (82%) had a history of other sexually transmitted infections during follow-up. Following SVR, aspartate transferase (AST) and alanine transaminase (ALT) decreased (p < 0.001), while total cholesterol, low-density lipoprotein, and triglycerides increased (p < 0.01). The median CD4+/CD8 + ratio increased from 0.91 to 0.97 (p = 0.012). NPZ-4 improved from 0.75 to 0.91 (p = 0.004). The median DT score increased from 1.7 to 2.7 (p = 0.045), but the PHQ-9 score remained unchanged. Conclusion: HCV coinfection is common in this group of high-risk PWH, highlighting the need for regular screening, early diagnosis, and treatment. There was a modest improvement in the CD4+/CD8 + T-cell ratio and cognitive performance after DAA therapy in patients who achieved SVR. Future studies should examine potential neuropsychiatric impacts during early HCV infection as well as the longer-term neuropsychiatric outcomes after DAA treatment with SVR.

Unique HIV Risk Factors and Prevention Needs for Transgender Women and Cisgender Men Who Have Sex with Men in Bangkok, Thailand.

Background: Transgender women (TGW) and cisgender men who have sex with men (cis-MSM) are often grouped together as key populations. We evaluated behavioral and other characteristics that may distinguish TGW from cis-MSM in Bangkok, Thailand. Methods: We enrolled into an 18-month cohort cis-MSM and TGW 18-35 years of age without HIV, who reported anal intercourse plus condomless anal intercourse, multiple partners, transactional sex, and/or sexually transmitted infection. Robust multivariable Poisson regression was used to estimate adjusted prevalence ratios (aPRs) and confidence intervals (95% CIs) for associations with being a TGW. Among TGW, logistic regression with generalized estimating equations was used to estimate adjusted odds ratios (aORs) and 95% CIs for associations with taking hormones and having undergone gender affirmation surgery (GAS). Results: From 2017 to 2019, 660 cis-MSM and 348 TGW were enrolled. Compared to cis-MSM, TGW were more likely to be attracted to mostly/only men (aPR: 3.79, 95% CI: 1.57-9.13), have a higher monthly income (aPR: 1.25, 95% CI: 1.04-1.50), have lived in their current residence for <1 year (aPR: 1.21, 95% CI: 1.01-1.46), have engaged in sex work (aPR: 1.48, 95% CI: 1.23-1.77), and be less likely to have ever undergone HIV testing (aPR: 0.83, 95% CI: 0.70-0.98). Among TGW, 149 (42.8%) were taking hormones and 33 (9.5%) had undergone GAS. GAS was more common among TGW who ever used methamphetamines (aOR: 1.55, 95% CI: 1.00-2.41) and those >23 years (18-20-year olds aOR: 0.17, 95% CI: 0.05-0.55; 21-23-year olds aOR: 0.36, 95% CI: 0.20-0.65). Conclusions: TGW and cis-MSM are unique populations; tailored, gender-affirming, differentiated models of HIV prevention and care are necessary to address vulnerabilities specific to each key population.

Distinct mucosal and systemic immunological characteristics in transgender women potentially relating to HIV acquisition.

Transgender women (TGW) are disproportionally affected by HIV infection, with a global estimated prevalence of 19.9%, often attributed to behavioral risk factors, with less known about biological factors. We evaluated potential biological risk factors for HIV acquisition in TGW at the sites of viral entry by assessing immune parameters of the neovaginal surface and gut mucosa. The neovagina in TGW, compared with the vagina in cisgender women (CW), shows distinct cell composition and may pose a more inflammatory environment, evidenced by increased CD4+ T cell activation and higher levels of soluble markers of inflammation (C-reactive protein, soluble CD30). Increased inflammation may be driven by microbiome composition, as shown by a greater abundance of Prevotella and a higher Shannon Diversity Index. In addition, we have observed higher frequency of CD4+CCR5+ target cells and decreased DNA methylation of the CCR5 gene in the gut mucosa of TGW compared with CW and men who have sex with men, which was inversely correlated with testosterone levels. The rectal microbiome composition in TGW appears to favor a proinflammatory milieu as well as mucosal barrier disruption. Thus, it is possible that increased inflammation and higher frequencies of CCR5-expressing target cells at sites of mucosal viral entry may contribute to increased risk of HIV acquisition in TGW, with further validation in larger studies warranted.

Estradiol and Testosterone Concentrations Among Thai Transgender Women in a Transgender-Led, Integrated Gender-Affirming Care and Sexual Health Clinic: A Real-World Analysis.

Purpose: Feminizing hormone therapy (FHT) is used by many transgender women as a pharmacological method to mitigate gender dysphoria. However, information on hormone concentrations among those who use FHT is lacking. We aimed to determine the proportion of Thai transgender women who were using FHT who had hormone concentrations within target ranges in a real-world clinic setting. Methods: Transgender women who attended Tangerine Clinic in Bangkok, Thailand, reported current use of FHT at clinic entry, and tested for both blood estradiol (E2) and total testosterone (TT) concentrations were included in the analysis. Hormone target concentrations were defined as 100-200 pg/mL for E2 and <50 ng/dL for TT. Results: Of 1534 transgender women included, 2.5% had undergone orchiectomy, and 524 (34.2%) had any hormones within target concentrations. Median (interquartile range) E2 and TT concentrations at baseline were 29 (14.3-45.3) pg/mL and 298.5 (22-646) ng/dL, respectively. Among those who had any hormones within target concentrations, 28 (1.8%), 11 (0.7%), and 485 (31.6%) had both hormones, only E2, and only TT within target concentrations, respectively. Among 1010 (65.8%) transgender women who had neither hormone within target concentrations, 989 (64.5%) and 21 (1.4%) had suboptimal and supraphysiological E2 concentrations, respectively. Among those who came to at least one follow-up visit (n=302), 165 (54.6%) transgender women managed to achieve or maintain either hormone within target concentrations. Conclusion: One-third of Thai transgender women who were using FHT had any hormones within target concentrations at baseline in this real-world setting study. Most transgender women who had neither hormone within target concentrations had suboptimal rather than supraphysiological E2 concentrations. More than half managed to achieve or maintain at least one hormone concentration within target concentrations at follow-up visits, suggesting a positive effect from attending a trans-led, integrated gender-affirming care and sexual health service.

Factors associated with testing for HIV and other sexually transmitted infections in men who have sex with men and transgender women in Bangkok, Thailand.

BACKGROUND: Routine screening for HIV and other sexually transmitted infections (STIs) facilitates early diagnosis and treatment, thereby preventing morbidity and onward transmission. We estimated the prevalence of prior HIV/STI testing among men who have sex with men (MSM) and transgender women (TGW) in Bangkok, Thailand, and identified factors associated with prior testing. METHODS: Cross-sectional analyses were performed using data collected at enrollment into an HIV incidence cohort. From April to October 2017, MSM and TGW were enrolled if they were aged 18-35 years, reported anal intercourse with a male or TGW partner, and reported behavioral vulnerability to HIV. Participants answered questions about demographics, sexual behaviors, and lifetime HIV/STI testing history. Multivariable robust Poisson regression was used to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for factors potentially associated with prior testing. RESULTS: Among 1,014 participants, 348 (34.3%) were TGW and the median age was 21.6 (interquartile range 20.0-24.8) years. Prior testing for HIV was reported by 421 (41.5%) and for other STIs by 268 (26.4%). HIV testing was more common among participants aged ≥ 22 years (RR 1.37 [95% CI 1.13-1.67]), with college education as compared to secondary or less (RR 1.37 [95% CI 1.08-1.72]), and who met male sexual partners online (RR 1.52 [95% CI 1.24-1.85]), but lower among participants attracted to both men and women as compared to men only (RR 0.64 [95% CI 0.51-0.81]) and who met male sexual partners in bars (RR 0.83 [95% CI 0.72-0.97]). Similar associations were observed with prior testing for other STIs, including increased testing among participants with college education (RR 1.52 [95% CI 1.11-2.09]) and who met male sexual partners online (RR 1.73 [95% CI 1.30-2.31]), but lower among participants attracted to both men and women (RR 0.70 [95% CI 0.51-0.96]) and who met male sexual partners in bars (RR 0.67 [95% CI 0.54-0.83]). CONCLUSIONS: Despite behavioral vulnerability, prior testing for HIV and other STIs was uncommon. Online engagement strategies may be effectively reaching Thai MSM and TGW who meet sexual partners online, but new interventions are needed to encourage testing among younger, less educated, and bisexual MSM and TGW.

Acceptability and satisfaction towards self-collection for chlamydia and gonorrhoea testing among transgender women in Tangerine Clinic, Thailand: shifting towards the new normal.

INTRODUCTION: Provider-collected swabs are an unappealing procedure for many transgender women and may have led to suboptimal rates of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) testing. Self-collection for CT/NG testing is recommended for men who have sex with men. However, the information on acceptability and clinical performance to support a recommendation for transgender women is lacking. We aimed to determine the acceptability and satisfaction towards self-collection for CT/NG testing among Thai transgender women. METHODS: Thai transgender women who attended Tangerine Clinic (a transgender-led, integrated, gender-affirming care and sexual health services clinic in Bangkok, Thailand) between May and July 2020 and had condomless sexual intercourse within the past six months were offered to collect urine and perform self-swabs of pharyngeal, rectal, and if applicable, neovaginal compartments for pooled nucleic acid amplification testing for CT/NG infections. Participants received a diagram, video and oral instructions about how to perform self-collection procedure. Those who accepted self-collection were also offered to receive provider collection to evaluate the performance between the two methods. Self-administered questionnaires were used to assess satisfaction. RESULTS: Among 216 transgender women enrolled, 142 (65.7%) accepted self-collection. All who accepted had pharyngeal, rectal and urine samples collected. Of 31 transgender women who had undergone genital surgery, 28 (90.3%) accepted neovaginal self-swab. The acceptance rate increased from 46.2% in May to 84.5% in July 2020. One participant had an invalid result. All transgender women who accepted self-collection could perform it without assistance, and 82.8% were highly satisfied with the method. None reported dissatisfaction. Due to the COVID-19 pandemic, provider collection services were discontinued early, and only eight transgender women were able to perform both methods for performance evaluation. The performance agreement was 100%. CONCLUSIONS: Thai transgender women had high acceptability and satisfaction towards self-collection for CT/NG testing. The performance was promising compared to provider collection. Our results support the implementation of self-collection to the sexually transmitted infection services, particularly during the COVID-19 pandemic where physical distancing is the new normal. A larger study is warranted to determine the performance of self-collection for CT/NG testing in each anatomical compartment and confirm the performance between self-collection and provider collection.

Risk Factors for HIV sero-conversion in a high incidence cohort of men who have sex with men and transgender women in Bangkok, Thailand.

BACKGROUND: We measured Human Immunodeficiency (HIV) incidence, retention, and assessed risk factors for seroconversion among two previously unreported cohorts of men who have sex with men (MSM) and Transgender Women (TGW) in Bangkok, Thailand between 2017 and 2019. METHODS: We conducted an 18-month prospective cohort study of HIV-uninfected Thai cisgender men and TGW aged between 18 and 35 years who reported sex with men in the past six months and at least one additional risk factor for HIV infection. HIV and syphilis testing and computer-based behavioral questionnaires were administered at each visit. We utilized Poisson regression to calculate HIV incidence rates. A survival random forest model identified the most predictive risk factors for HIV sero-conversion and then used in a survival regression tree model to elucidate hazard ratios for individuals with groups of selected risk factors. Cox proportional hazards (pH) regression evaluated the strength of association between individual covariates and risk of sero-conversion. FINDINGS: From April 2017-October 2019, 1,184 participants were screened, 167 were found ineligible, and 1,017 enrolled. Over the 18-month study, visit retention was 93·4% (95% CI 91·6%-94·8%) and HIV incidence was 3·73 per 100 person-years (95% CI 2·79-5·87). Utilizing survival regression tree modeling, those who were 18-20 years of age, reported sexual attraction to mostly or only men, and had five or more lifetime sexual partners were 4·9 times more likely to seroconvert compared to other cohort participants. Factors associated with HIV incidence utilizing Cox pH regression included sexual attraction to mostly or only men (adjusted hazard ratio (aHR) 14·9 (95% CI 20·1-107·9), younger age (18-19 years, aHR 10·88 (95% CI 4·12-28·7), five or greater lifetime sexual partners (aHR 2·0, 95%CI 1·1-3·6), inconsistent condom use with casual partners (aHR 2·43, 95% CI 1·3-4·5), and prior HIV testing (adjusted HR 2·0, 95% CI 1·1-3·5). INTERPRETATION: Interpretation HIV incidence remains high among Bangkok-based MSM and TGW. These key populations expressed high interest in participating in efficacy evaluation of future prevention strategies and had high retention in this 18 month study. FUNDING: Funding US National Institute of Allergy and Infectious Diseases (NIAID), Division of AIDS Interagency Agreements (DAIDS) and U.S. Department of the Army.

Brief Report: Group Sex and Methamphetamine Use Fuel an Explosive Epidemic of Hepatitis C Among HIV-Infected Men Who Have Sex With Men in Bangkok, Thailand.

BACKGROUND: Increased rates of hepatitis C virus (HCV) infection among HIV-infected men who have sex with men (MSM) and who deny injecting drugs have been reported in resource-rich settings. SETTING: We measured HCV prevalence and incidence in a predominantly MSM cohort with acute HIV infection in Bangkok, Thailand. METHODS: In 2009-2018, participants with acute HIV infection were enrolled into the SEARCH010/RV254 cohort. HCV antibody was measured at enrollment and at least once annually. Infection was confirmed with HCV RNA. Risk factors for HCV were analyzed by proportional hazards regression, with hazard ratios (HRs) calculated in a multivariable model. RESULTS: Of 573 participants, 94% were MSM, with a median age of 26 years (range 18-70 years). The prevalence of HCV antibody was 9 of the 573, or 1.6% [95% confidence interval (CI): 0.7% to 3.0%]. In 1883 person-years (PY) of follow-up, 39 incident cases were identified (20.7 per 1000 PY, 95% CI: 15.1 to 28.3). All incident cases were identified from 2014 onward, and incidence rose from a range of 7.5-11.4 per 1000 PY between 2014 and 2016 to 44.8 per 1000 PY in 2018 (P = 0.001). Most cases (97.4%) were MSM and denied injecting drugs (37 of the 39, 94.5%). In multivariate analysis, methamphetamine use [adjusted HR 2.33 (95% CI: 1.13 to 4.8), P = 0.022], group sex [adjusted HR 2.54 (95% CI: 1.26 to 5.12), P = 0.009], and a history of positive Treponema pallidum hemagglutination or rapid plasma reagin [adjusted HR 2.43 (95% CI: 1.22 to 4.85), P = 0.012] were significantly associated with incident HCV. CONCLUSION: We report an HCV epidemic among this cohort of HIV-infected Bangkok-based MSM. Access to timely HCV diagnosis and treatment is needed to prevent morbidity and to decrease onward transmission.

High hepatitis C cure rates among black and nonblack human immunodeficiency virus-infected adults in an urban center.

Hepatitis C virus (HCV) cure rates have been similar in patients with and without human immunodeficiency virus (HIV) coinfection; however, in the ION-4 study, black patients treated with ledipasvir/sofosbuvir (LDV/SOF) were significantly less likely to achieve cure (90%) compared to nonblack patients (99%). There are limited real-world data on the effectiveness of oral direct-acting antivirals (DAAs) in predominantly minority HIV/HCV coinfected populations. We analyzed HCV treatment outcomes among 255 HCV coinfected patients initiating DAAs between February 2014 and March 2016 in an urban clinic in Baltimore, Maryland. To facilitate adherence, patients received standardized HIV nurse/pharmacist support, which included nurse visits and telephone calls. Median age was 43 years, 88% were black, 73% male, 69% had a history of injection drug use, 45% a history of hazardous alcohol use, and 57% a comorbid psychiatric diagnosis. Median CD4 count was 577 (interquartile range, 397-820) cells/mm3 ; most (97%) were on antiretroviral therapy, had HIV RNA <20 copies/mL (87%), and were infected with HCV genotype 1 (98%). Over 60% had significant fibrosis (Fibrosis-4 Index score 1.45-3.25 [44%] and >3.25 [17%, cirrhosis]) and 30% were HCV treatment experienced. The majority of patients received LDV/SOF with or without ribavirin (91%) and were treated for 12 weeks. Overall, the sustained virological response rate was 97% (95% confidence interval [CI], 93-98) and did not vary by race (black, 96% [95% CI, 93-98]; nonblack, 97%, [95% CI, 83-99]), history of injection drug use, alcohol use, or psychiatric diagnosis. CONCLUSION: HCV treatment was highly effective among HIV-infected patients who received care within an integrated nurse/pharmacist adherence support program. These results suggest that race and psychosocial comorbidity may not be barriers to HCV elimination. (Hepatology 2017;66:1402-1412).

Barriers to Hepatitis C Virus (HCV) Treatment Initiation in Patients With Human Immunodeficiency Virus/HCV Coinfection: Lessons From the Interferon Era.

BACKGROUND: Hepatitis C is a major cause of mortality among human immunodeficiency virus (HIV)-infected patients, yet hepatitis C virus (HCV) treatment uptake has historically been low. Although the removal of interferon removes a major barrier to HCV treatment uptake, oral therapies alone may not fully eliminate barriers in this population. METHODS: Within the Johns Hopkins Hospital HIV cohort, a nested case-control study was conducted to identify cases, defined as patients initiating HCV treatment between January 1996 and 2013, and controls, which were selected using incidence density sampling (3:1 ratio). Controls were matched to cases on date of enrollment. Conditional logistic regression was used to evaluate factors associated with HCV treatment initiation. RESULTS: Among 208 treated cases and 624 untreated controls, the presence of advanced fibrosis (odds ratio [OR], 2.23; 95% confidence interval [CI], 1.26-3.95), recent active drug use (OR, 0.36; 95% CI, 0.19-0.69), and non-black race (OR, 2.01; 95% CI, 1.26-3.20) were independently associated with initiation of HCV therapy. An increasing proportion of missed visits was also independently associated with lower odds of HCV treatment (25%-49% missed visits [OR, 0.49; 95% CI, 0.27-0.91] and ≥50% missed visits [OR, 0.24; 95% CI, 0.12-0.48]). CONCLUSIONS: Interferon-free treatments may not be sufficient to fully overcome barriers to HCV care in HIV-infected patients. Interventions to increase engagement in care for HIV and substance use are needed to expand HCV treatment uptake.

Transgender populations and HIV: unique risks, challenges and opportunities.

Due to unique social, behavioural, structural and biological issues, transgender (TG) populations, especially TG women, are at high risk for HIV acquisition. This increased risk is multifactorial, due to differing psychosocial risk factors, poorer access to TG-specific healthcare, a higher likelihood of using exogenous hormones or fillers without direct medical supervision, interactions between hormonal therapy and antiretroviral therapy, and direct effects of hormonal therapy on HIV acquisition and immune control. Further research is needed to elucidate these mechanisms of risk and to help design interventions to reduce HIV risk among transgender populations.

The Facial Appearance Inventory: Development and Preliminary Evidence for Reliability and Validity in People with HIV and Lipoatrophy.

BACKGROUND: Facial lipoatrophy is common in people on antiretroviral (ARV) regimens for HIV/AIDS and can impair health-related quality of life. OBJECTIVES: We developed the Facial Appearance Inventory (FAI) to measure the impact of ARV-associated facial lipoatrophy. METHODS: Qualitative methods were used to identify key concerns of people with facial lipoatrophy. The major concerns were used to identify 24 items for the FAI. The FAI was administered to a cross-sectional sample of 96 people with HIV and facial lipoatrophy and compared to the established Assessment of Body Change Distress (ABCD) and MOS-HIV questionnaires. RESULTS: Mean age was 48.8 years, 87.5% were men, 69.8% were Caucasian, and 60% had some college education. Mean CD4 count was 435 cells/mm(3). There were few missing data, and the summary score showed no floor or ceiling effects, with a mean (SD) of 25.6 (17.9). Cronbach's alpha for the scale was 0.98. FAI items satisfied criteria for convergent and discriminant construct validity. FAI items were more strongly correlated with mental health domains (R = 0.33) than with physical health domains (R = 0.26) on the MOS-HIV. Patients with greater severity of lipoatrophy had significantly worse scores than those with less severity (James 3-4, vs. James 0-2). There were no significant differences for FAI scores by age group, income group, CD4 cell count, or HIV viral load group. Those with less education and those with darker skin types reported less impairment (P < .05). CONCLUSIONS: The 24-item FAI shows evidence for reliability, validity, and usefulness as a measure of the impact of facial lipoatrophy.

Reliability and validity of Thai versions of the MOS-HIV and SF-12 quality of life questionnaires in people living with HIV/AIDS.

BACKGROUND/AIM: As Thai people living with HIV/AIDS gain increasing access to antiretroviral (ARV) therapy, it is important to evaluate the impact this has not only on clinical outcomes, but also on patients' functional status and well-being. In this study, we translated, culturally adapted and tested the reliability and validity of two widely-used health-related quality of life questionnaires - the MOS-HIV Health Survey and the SF-12 - in people living with HIV/AIDS in Northern Thailand. METHODS: Questionnaires were administered to 100 patients at community hospital outpatient ARV clinics in northern Thailand. Reliability was estimated using Cronbach's alpha, while evidence for validity was tested using known-groups comparison based on CD4 group, symptom distress score, bed days and days of reduced activity in the past three months. RESULTS: Patients' median age was 36, with 58% female, 58% working as laborers, and 60% completing at least primary education. Median CD4 count was 218 cells/mm3. There were no missing data. For the MOS-HIV and SF-12, mean physical summary scores were 53.1 and 49.0 respectively; mean mental summary scores were 53.4 and 45.6, respectively. Internal consistency coefficients were >0.7 for all but one scale, the PF scale (0.67). As hypothesized, scores were slightly to moderately correlated with CD4 count, symptom score, number of days in bed or with reduced activity. Correlations were higher with physical health scores than with mental health scales. The MOS-HIV discriminated clinical known groups slightly better than the SF-12. CONCLUSION: Both the MOS-HIV and the shorter SF-12 were successfully adapted for people with HIV/AIDS in Northern Thailand, and showed encouraging evidence for reliability and validity. These patient reported questionnaires could be valuable tools in evaluating therapeutic interventions and other innovations in health and social services, and to estimate health needs and population disability related to HIV.

An assessment of vulnerability to HIV infection of boatmen in Teknaf, Bangladesh.

BACKGROUND: Mobile population groups are at high risk for contracting HIV infection. Many factors contribute to this risk including high prevalence of risky behavior and increased risk of violence due to conflict and war. The Naf River serves as the primary border crossing point between Teknaf, Bangladesh and Mynamar [Burma] for both official and unofficial travel of people and goods. Little is known about the risk behavior of boatmen who travel back and forth between Teknaf and Myanmar. However, we hypothesize that boatmen may act as a bridging population for HIV/AIDS between the high-prevalence country of Myanmar and the low-prevalence country of Bangladesh. METHODS: Methods included initial rapport building with community members, mapping of boatmen communities, and in-depth qualitative interviews with key informants and members from other vulnerable groups such as spouses of boatmen, commercial female sex workers, and injecting drug users. Information from the first three stages was used to create a cross-sectional survey that was administered to 433 boatmen. RESULTS: Over 40% of the boatmen had visited Myanmar during the course of their work. 17% of these boatmen had sex with CSW while abroad. There was a significant correlation found between the number of nights spent in Myanmar and sex with commercial sex workers.In the past year, 19% of all boatmen surveyed had sex with another man. 14% of boatmen had participated in group sex, with groups ranging in size from three to fourteen people. Condom use was rare {0 to 4.7% during the last month}, irrespective of types of sex partners. Regression analysis showed that boatmen who were 25 years and older were statistically less likely to have sexual intercourse with non- marital female partners in the last year compared to the boatmen aged less than 25 years. Similarly deep-sea fishing boatmen and non-fishing boatmen were statistically less likely to have sexual intercourse with non- marital female partners in the last year compared to the day long fishing boatmen adjusting for all other variables. Boatmen's knowledge regarding HIV transmission and personal risk perception for contracting HIV was low. CONCLUSION: Boatmen in Teknaf are an integral part of a high-risk sexual behaviour network between Myanmar and Bangladesh. They are at risk of obtaining HIV infection due to cross border mobility and unsafe sexual practices. There is an urgent need for designing interventions targeting boatmen in Teknaf to combat an impending epidemic of HIV among this group. They could be included in the serological surveillance as a vulnerable group. Interventions need to address issues on both sides of the border, other vulnerable groups, and refugees. Strong political will and cross border collaboration is mandatory for such interventions.