Barriers to childhood tuberculosis case detection and management in Cambodia: the perspectives of healthcare providers and caregivers.

BACKGROUND: Diagnosis and treatment of tuberculosis (TB) in children remain challenging, particularly in resource-limited settings. Healthcare providers and caregivers are critical in improving childhood TB screening and treatment. This study aimed to determine the barriers to childhood TB detection and management from the perspectives of healthcare providers and caregivers in Cambodia. METHOD: We conducted this qualitative study between November and December 2020. Data collection included in-depth interviews with 16 healthcare providers purposively selected from four operational districts and 28 caregivers of children with TB and children in close contact with bacteriologically confirmed pulmonary TB residing in the catchment areas of the selected health centers. Data were analyzed using thematic analyses. RESULTS: Mean ages of healthcare providers and caregivers were 40.2 years (standard deviation [SD] 11.9) and 47.9 years (SD 14.6), respectively. Male was predominant among healthcare providers (93.8%). Three-fourths of caregivers were female, and 28.6% were grandparents. Inadequate TB staff, limited knowledge on childhood TB, poor collaboration among healthcare providers in different units on TB screening and management, limited quality of TB diagnostic tools, and interruption of supplies of childhood TB medicines due to maldistribution from higher levels to health facilities were the key barriers to childhood TB case detection and management. Caregivers reported transportation costs to and from health facilities, out-of-pocket expenditure, time-consuming, and no clear explanation from healthcare providers as barriers to childhood TB care-seeking. Aging caregivers with poor physical conditions, lack of collaboration from caregivers, ignorance of healthcare provider's advice, and parent movement were also identified as barriers to childhood TB case detection and management. CONCLUSIONS: The national TB program should further invest in staff development for TB, scale-up appropriate TB diagnostic tools and ensure its functionalities, such as rapid molecular diagnostic systems and X-ray machines, and strengthen childhood TB drug management at all levels. These may include drug forecasting, precise drug distribution and monitoring mechanism, and increasing community awareness about TB to increase community engagement.

What are the determinants of antiretroviral therapy adherence among stable people living with HIV? A cross-sectional study in Cambodia.

BACKGROUND: Understanding context-specific determinants of antiretroviral therapy (ART) adherence is crucial for developing tailored interventions for improving health outcomes and achieving the UNAIDS' third 95% target. This cross-sectional study explores factors associated with ART adherence among stable people living with HIV on ART in Cambodia. METHODS: We used baseline survey data from a quasi-experimental study conducted in 2021. The participants were recruited from 20 ART clinics in nine provinces for face-to-face interviews. A structured questionnaire collected information on sociodemographic characteristics, ART adherence, perceived ART self-efficacy, mental health, quality of life, stigma, and discrimination. We conducted bivariate and multiple logistic regression analyses to identify factors associated with ART adherence. RESULTS: Out of the 4101 participants, 86.5% reported adhering to ART in the past two months. The adjusted odds of ART adherence were significantly higher among participants in older age groups than those aged 15-29, participants with elevated cholesterol than those without it, participants who exhibited strong self-efficacy in health responsibility to maintain life than those with poor self-efficacy in health responsibility, participants who scored < 3 on the stigma and discrimination scale than those who scored ≥ 3, participants who scored ≥ 42 on the mental component of the quality-of-life scale than those who scored < 42. The adjusted odds of ART adherence were significantly lower in participants who earned > 301 USD per month than those who earned ≤ 100 USD per month. CONCLUSION: The ART adherence rate among stable people living with HIV in this study was comparable to that of the general people living with HIV in Cambodia. The results suggest the need for innovative interventions to further reduce stigma and discrimination and strategies to improve the self-efficacy and mental health of people living with HIV to improve ART adherence.

They do not have symptoms - why do they need to take medicines? Challenges in tuberculosis preventive treatment among children in Cambodia: a qualitative study.

BACKGROUND: Latent tuberculosis (TB) infection has been known as a seedbed for TB disease later in life. The interruption from latent TB infection to TB disease can be done through TB preventive treatment (TPT). In Cambodia, only 40.0% of children under five years old who were the household contacts to bacteriologically confirmed TB cases were initiated with TPT in 2021. Scientific studies of context-specific operational challenges in TPT provision and uptake among children are scarce, particularly in high TB-burden countries. This study identified challenges in TPT provision and uptake among children in Cambodia from the perspective of healthcare providers and caregivers. METHODS: Between October and December 2020, we conducted in-depth interviews with four operational district TB supervisors, four clinicians and four nurses in charge of TB in referral hospitals, four nurses in charge of TB in health centers, and 28 caregivers with children currently or previously on TB treatment or TPT, and those who refused TPT for their eligible children. Data were audio recorded along with field notetaking. After verbatim transcription, data analyses were performed using a thematic approach. RESULTS: The mean age of healthcare providers and caregivers were 40.19 years (SD 12.0) and 47.9 years (SD 14.6), respectively. Most healthcare providers (93.8%) were male, and 75.0% of caregivers were female. More than one-fourth of caregivers were grandparents, and 25.0% had no formal education. Identified key barriers to TPT implementation among children included TPT side effects, poor adherence to TPT, poor understanding of TPT among caregivers, TPT risk perception among caregivers, TPT's child-unfriendly formula, TPT supply-chain issues, caregivers' concern about the effectiveness of TPT, being non-parental caregivers, and poor community engagement. CONCLUSION: Findings from this study suggest that the national TB program should provide more TPT training to healthcare providers and strengthen supply chain mechanisms to ensure adequate TPT drug supplies. Improving community awareness of TPT among caregivers should also be intensified. These context-specific interventions will play a crucial role in expanding the TPT program to interrupt the development from latent TB infection to active and ultimately lead to ending TB in the country.

Tuberculosis in older adults: case studies from four countries with rapidly ageing populations in the western pacific region.

BACKGROUND: The Western Pacific Region has one of the fastest-growing populations of older adults (≥ 65 years) globally, among whom tuberculosis (TB) poses a particular concern. This study reports country case studies from China, Japan, the Republic of Korea, and Singapore reflecting on their experiences in managing TB among older adults. FINDINGS: Across all four countries, TB case notification and incidence rates were highest among older adults, but clinical and public health guidance focused on this population was limited. Individual country reports illustrated a range of practices and challenges. Passive case finding remains the norm, with limited active case finding (ACF) programs implemented in China, Japan, and the Republic of Korea. Different approaches have been trialled to assist older adults in securing an early diagnosis, as well as adhering to their TB treatment. All countries emphasised the need for person-centred approaches that include the creative application of new technology and tailored incentive programs, as well as reconceptualisation of how we provide treatment support. The use of traditional medicines was found to be culturally entrenched among older adults, with a need for careful consideration of their complementary use. TB infection testing and the provision of TB preventive treatment (TPT) were underutilised with highly variable practice. CONCLUSION: Older adults require specific consideration in TB response policies, given the burgeoning aging population and their high TB risk. Policymakers, TB programs and funders must invest in and develop locally contextualised practice guidelines to inform evidence-based TB prevention and care practices for older adults.

Knowledge, attitude, and practices regarding childhood tuberculosis detection and management among health care providers in Cambodia: a cross-sectional study.

BACKGROUND: The World Health Organization (WHO) estimated that 29% of global tuberculosis (TB) and almost 47% of childhood TB cases were not reported to national TB programs in 2019. In Cambodia, most childhood TB cases were reported from health facilities supported by the Global Fund to Fight AIDS, Tuberculosis, and Malaria in 2019. This study aimed to compare the healthcare providers' knowledge, attitude, and practices (KAP) on childhood TB case detection in operational districts (ODs) with high and low childhood TB case detection in Cambodia. METHODS: We conducted a cross-sectional study between November and December 2020 among healthcare providers in 10 purposively selected ODs with high childhood TB case detection and 10 ODs with low childhood TB case detection. A total of 110 healthcare providers from referral hospitals (RHs) and 220 from health centers (HCs) were interviewed. We collected information on socio-demographic characteristics, training, and KAP on childhood TB. Pearson's Chi-square or Fisher's exact and Student's t-tests were performed to explore the differences in KAP of healthcare providers from ODs with low vs. high childhood TB detection. RESULTS: Of the 330 respondents, 193 were from ODs with high childhood TB case detection, and 66.67% were from HCs. A significantly higher proportion (46.11%) of respondents from ODs with high childhood TB case detection received training on childhood TB within the past two years than those from low childhood TB case detection ODs (34.31%) (p = 0.03). Key knowledge on childhood TB was not significantly different among respondents from ODs with high and low childhood TB case detection. A significantly higher proportion of respondents from ODs with high childhood TB case detection had a good attitude (98.96 vs. 97.08%, p = 0.002) and performed good practices (58.55 vs. 45.26%, p = 0.02) on contact investigation in the community than those from low childhood TB case detection ODs. CONCLUSIONS: Healthcare providers from ODs with high childhood TB detection had better attitudes and practices towards childhood TB. The attitudes and practices need to be improved among healthcare providers in ODs with low case detection. Further investment in training and experience sharing on childhood TB case detection among healthcare providers is needed to improve childhood TB case detection.

COVID-19 and the shifting organisation of sex work markets in Singapore.

While past studies have sought to capture how the COVID-19 pandemic has impacted on the health and sexual lives of sex workers internationally, less attention has been paid to the reorganisation of sex markets as a result of COVID-19. We conducted a sequential exploratory mixed methods study using in-depth interviews, cyber ethnography and surveyor-administered structured surveys among sex workers. We report two key findings on how the pandemic has impacted sex markets in Singapore. First, the organisation of sex markets shifted as a result of lockdown and associated movement control measures. This shift was characterised by the out-migration of sex workers, the reduction in supply and demand for in-person sex work, and a shift towards online spaces. Second, we found that sex workers experienced greater economic hardship as a result of such changes. Given the potential shifts in sex markets as a result of the pandemic, we adopt a World Health Organisation Health Workplace Framework and Model to identify interventions to improve the occupational safety and health of sex workers in a post-COVID-19 era.

High-resolution fast-tomography brain-imaging beamline at the Taiwan Photon Source.

The new Brain Imaging Beamline (BIB) of the Taiwan Photon Source (TPS) has been commissioned and opened to users. The BIB and in particular its endstation are designed to take advantage of bright unmonochromatized synchrotron X-rays and target fast 3D imaging, ∼1 ms exposure time plus very high ∼0.3 µm spatial resolution. A critical step in achieving the planned performances was the solution to the X-ray induced damaging problems of the detection system. High-energy photons were identified as their principal cause and were solved by combining tailored filters/attenuators and a high-energy cut-off mirror. This enabled the tomography acquisition throughput to reach >1 mm3 min-1, a critical performance for large-animal brain mapping and a vital mission of the beamline.

Duration and determinants of delayed tuberculosis diagnosis and treatment in high-burden countries: a mixed-methods systematic review and meta-analysis.

BACKGROUND: Thirty countries with the highest tuberculosis (TB) burden bear 87% of the world's TB cases. Delayed diagnosis and treatment are detrimental to TB prognosis and sustain TB transmission in the community, making TB elimination a great challenge, especially in these countries. Our objective was to elucidate the duration and determinants of delayed diagnosis and treatment of pulmonary TB in high TB-burden countries. METHODS: We conducted a systematic review and meta-analysis of quantitative and qualitative studies by searching four databases for literature published between 2008 and 2018 following PRISMA guidelines. We performed a narrative synthesis of the covariates significantly associated with patient, health system, treatment, and total delays. The pooled median duration of delay and effect sizes of covariates were estimated using random-effects meta-analyses. We identified key qualitative themes using thematic analysis. RESULTS: This review included 124 articles from 14 low- and lower-middle-income countries (LIC and LMIC) and five upper-middle-income countries (UMIC). The pooled median duration of delays (in days) were-patient delay (LIC/LMIC: 28 (95% CI 20-30); UMIC: 10 (95% CI 10-20), health system delay (LIC/LMIC: 14 (95% CI 2-28); UMIC: 4 (95% CI 2-4), and treatment delay (LIC/LMIC: 14 (95% CI 3-84); UMIC: 0 (95% CI 0-1). There was consistent evidence that being female and rural residence was associated with longer patient delay. Patient delay was also associated with other individual, interpersonal, and community risk factors such as poor TB knowledge, long chains of care-seeking through private/multiple providers, perceived stigma, financial insecurities, and poor access to healthcare. Organizational and policy factors mediated health system and treatment delays. These factors included the lack of resources and complex administrative procedures and systems at the health facilities. We identified data gaps in 11 high-burden countries. CONCLUSIONS: This review presented the duration of delays and detailed the determinants of delayed TB diagnosis and treatment in high-burden countries. The gaps identified could be addressed through tailored approaches, education, and at a higher level, through health system strengthening and provision of universal health coverage to reduce delays and improve access to TB diagnosis and care. PROSPERO registration: CRD42018107237.

HIV Pre-Exposure Prophylaxis, Condoms, or Both? Insights on Risk Compensation Through a Discrete Choice Experiment and Latent Class Analysis Among Men Who Have Sex With Men.

OBJECTIVES: We considered how decision making around human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) among gay, bisexual, and other men who have sex with men (GBMSM) is made in the context of one's perceived risk of HIV acquisition and the availability of condoms. METHODS: We recruited 648 GBMSM aged 18 years old and residing in Singapore through Grindr. Participants were given information on PrEP and participated in a discrete choice experiment requiring them to choose between 2 baskets of PrEP attributes and compare the chosen "PrEP only" option to default options of "condoms only" or "PrEP with condoms." Generalized multinomial logit model was used to examine the scaling effect and preference heterogeneity. Latent class analysis was conducted to examine preference heterogeneity in the sample. RESULTS: Latent class analysis revealed 3 classes of GBMSM: PrEP conservatives (53.9%), moderates (31.1%), and liberals (14.9%). PrEP conservatives were more likely to report greater utility when using condoms only compared with PrEP only, as well as PrEP with condoms, compared with PrEP only, and more likely to report the lowest utility for PrEP as perceived HIV risk increased. PrEP liberals were more likely to report greatest utilities for PrEP only compared with condoms only, as well as PrEP only compared with PrEP with condoms. The utility for PrEP was not affected by perceived risk of HIV or sexually transmitted infections when risks were low. CONCLUSION: This study provides some evidence for risk compensation among a class of GBMSM who already perceived themselves to be good candidates for PrEP before the discrete choice experiment.

Community-based model for the delivery of antiretroviral therapy in Cambodia: a quasi-experimental study protocol.

BACKGROUND: Multi-month dispensing (MMD) is the mainstay mechanism for clinically stable people living with HIV in Cambodia to refill antiretroviral therapy (ART) every 3-6 months. However, less frequent ART dispensing through the community-based ART delivery (CAD) model could further reduce the clients' and health facilities' burden. While community-based services have been recognized as an integral component of HIV response in Cambodia, their role and effectiveness in ART delivery have yet to be systematically assessed. This study aims to evaluate the CAD model's effectiveness on the continuum of care and treatment outcomes for stable people living with HIV in Cambodia. METHODS: We will conduct this quasi-experimental study in 20 ART clinics across the capital city and nine provinces between May 2021 and April 2023. Study sites were purposively selected based on the availability of implementing partners, the number of people living with HIV each clinic serves, and the accessibility of the clinics. In the intervention arm, approximately 2000 stable people living with HIV will receive ART and services from the CAD model. Another 2000 stable people living with HIV in the control arm will receive MMD-a standard care model for stable people living with HIV. The primary outcomes will be retention in care, viral load suppression, and adherence to ART. The secondary endpoints will include health providers' work burden, the model's cost-effectiveness, quality of life, mental health, social support, stigma, and discrimination. We will compare the outcome indicators within each arm at baseline, midline, and endline using descriptive and inferential statistics. We will evaluate the differences between the intervention and control arms using the difference-in-differences method. We will perform economic evaluations to determine if the intervention is cost-effective. DISCUSSION: This study will build the evidence base for future implementation and scale-up of CAD model in Cambodia and other similar settings. Furthermore, it will strengthen engagements with community stakeholders and further improve community mobilization, a vital pillar of the Cambodian HIV response. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04766710 . Registered 23 February 2021, Version 1.

The Impact of the Coronavirus Disease (COVID-19) on the Health and Social Needs of Sex Workers in Singapore.

We evaluated the impact of the coronavirus disease (COVID-19) on the sex work industry and assessed how it has impacted the health and social conditions of sex workers in Singapore. We conducted a sequential exploratory mixed methods study amidst the COVID-19 pandemic from April to October 2020, including in-depth interviews with 24 stakeholders from the sex work industry and surveyor-administered structured surveys with 171 sex workers. COVID-19 had a substantial impact on sex workers' income. The illegality of sex work, stigma, and the lack of work documentation were cited as exclusionary factors for access to alternative jobs or government relief. Sex workers had experienced an increase in food insecurity (57.3%), housing insecurity (32.8%), and sexual compromise (8.2%), as well as a decrease in access to medical services (16.4%). Being transgender female was positively associated with increased food insecurity (aPR = 1.23, 95% CI [1.08, 1.41]), housing insecurity (aPR = 1.28, 95% CI [1.03, 1.60]), and decreased access to medical services (aPR = 1.74, 95% CI [1.23, 2.46]); being a venue-based sex worker was positively associated with increased food insecurity (aPR = 1.46, 95% CI [1.00, 2.13]), and being a non-Singaporean citizen or permanent resident was positively associated with increased housing insecurity (aPR = 2.59, 95% CI [1.73, 3.85]). Our findings suggest that COVID-19 has led to a loss of income for sex workers, greater food and housing insecurity, increased sexual compromise, and reduced access to medical services for sex workers. A lack of access to government relief among sex workers exacerbated such conditions. Efforts to address such population health inequities should be implemented.

Association between retinal thickness variation and visual acuity change in neovascular age-related macular degeneration.

BACKGROUND: To assess the association between variation in retinal central subfield thickness (CSFT) with best-corrected visual acuity (BCVA) change in patients receiving vascular endothelial growth factor (VEGF) inhibitor therapy for neovascular age-related macular degeneration (nAMD). METHODS: CSFT measurements were obtained from 141 eyes (total 1300 scans). SD of CSFT was calculated. The eyes were categorised into CSFT variation tertiles. Multiple linear regression was used to examine the association between the CSFT tertiles and BCVA change at 12 mo, adjusting for differences in baseline demographic and clinical characteristics. RESULTS: At 12 mo, the mean BCVA of the high CSFT variation group (50.6 letters) was significantly lower than the low and moderate CSFT variation groups (57.5 and 59.8 letters, respectively), P = .02. The adjusted mean BCVA gains were +1.7, +7.2, and +7.8 letters in the high, moderate and low CSFT variation groups, respectively (P = .03). CONCLUSIONS: A greater variation in retinal thickness during VEGF inhibitor therapy for nAMD is associated with a less favourable visual outcome. CSFT stability is useful in prognosticating visual outcomes in VEGF inhibitor therapy for nAMD.

Retinal Vascular Signs and Cerebrovascular Diseases.

BACKGROUND: Cerebrovascular disease (CeVD), including stroke, is a leading cause of death globally. The retina is an extension of the cerebrum, sharing embryological and vascular pathways. The association between different retinal signs and CeVD has been extensively evaluated. In this review, we summarize recent studies which have examined this association. EVIDENCE ACQUISITION: We searched 6 databases through July 2019 for studies evaluating the link between retinal vascular signs and diseases with CeVD. CeVD was classified into 2 groups: clinical CeVD (including clinical stroke, silent cerebral infarction, cerebral hemorrhage, and stroke mortality), and sub-clinical CeVD (including MRI-defined lacunar infarct and white matter lesions [WMLs]). Retinal vascular signs were classified into 3 groups: classic hypertensive retinopathy (including retinal microaneurysms, retinal microhemorrhage, focal/generalized arteriolar narrowing, cotton-wool spots, and arteriovenous nicking), clinical retinal diseases (including diabetic retinopathy [DR], age-related macular degeneration [AMD], retinal vein occlusion, retinal artery occlusion [RAO], and retinal emboli), and retinal vascular imaging measures (including retinal vessel diameter and geometry). We also examined emerging retinal vascular imaging measures and the use of artificial intelligence (AI) deep learning (DL) techniques. RESULTS: Hypertensive retinopathy signs were consistently associated with clinical CeVD and subclinical CeVD subtypes including subclinical cerebral large artery infarction, lacunar infarction, and WMLs. Some clinical retinal diseases such as DR, retinal arterial and venous occlusion, and transient monocular vision loss are consistently associated with clinical CeVD. There is an increased risk of recurrent stroke immediately after RAO. Less consistent associations are seen with AMD. Retinal vascular imaging using computer assisted, semi-automated software to measure retinal vascular caliber and other parameters (tortuosity, fractal dimension, and branching angle) has shown strong associations to clinical and subclinical CeVD. Other new retinal vascular imaging techniques (dynamic retinal vessel analysis, adaptive optics, and optical coherence tomography angiography) are emerging technologies in this field. Application of AI-DL is expected to detect subclinical retinal changes and discrete retinal features in predicting systemic conditions including CeVD. CONCLUSIONS: There is extensive and increasing evidence that a range of retinal vascular signs and disease are closely linked to CeVD, including subclinical and clinical CeVD. New technology including AI-DL will allow further translation to clinical utilization.

Extent and selectivity of sexual orientation disclosure and its association with HIV and other STI testing patterns among gay, bisexual and other men who have sex with men.

OBJECTIVES: Gay, bisexual and other men who have sex with men (GBMSM) in Singapore may fear disclosing their sexual orientation to others due to negative societal attitudes, and the law that criminalises sexual relations between men, which may, in turn, impede access to HIV/sexually transmitted infection (STI)-related health services. This study attempts to determine how selective disclosure to varying social groups, and the extent of disclosure, may serve to impact HIV/STI testing patterns among GBMSM. METHODS: In this observational study, we recruited GBMSM in Singapore through an online cross-sectional survey disseminated via the smartphone app Grindr from 14 January to 11 February 2018. Respondents provided information on their sociodemographic characteristics, disclosure of sexual orientation towards other lesbian, gay, bisexual, transgender and questioning (LGBTQ) individuals, non-LGBTQ family members, non-LGBTQ friends and non-LGBTQ colleagues, along with their HIV/STI testing patterns. Extent of disclosure was defined as the number of social groups that a participant had disclosed his sexual orientation to. Statistical analyses were conducted through descriptive statistics, multivariable binary, ordinal, and multinomial logistic regression models. RESULTS: We recruited 1339 respondents, of which 1098 who had provided their response to questions on HIV/STI testing were included in the analytic sample. Multivariable analyses indicated that disclosure towards non-LGBTQ family members (adjusted OR [aOR] 1.85, 95% CI 1.12 to 3.07) and other LGBTQ individuals (aOR 1.63, 95% CI 1.12 to 2.37) were positively associated with recent HIV testing, whereas disclosure towards non-LGBTQ colleagues (aOR 1.56, 95% CI 1.09 to 2.22) was positively associated with regular HIV testing. Extent of disclosure exhibited a positive, dose-response relationship with all testing outcomes. CONCLUSIONS: Results indicate how the fear of being identified as an LGBTQ individual may deter GBMSM from getting tested for HIV and other STIs. Health services should bridge the gaps to accessing healthcare among individuals who fear being stigmatised for attending sexual health-specific clinics or being identified as GBMSM.

Estimating the size of key populations for HIV in Singapore using the network scale-up method.

OBJECTIVES: To develop a localised instrument and Bayesian statistical method to generate size estimates-adjusted for transmission error and barrier effects-of at-risk populations in Singapore. METHODS: We conducted indepth interviews and focus group to guide the development of the survey questionnaire. The questionnaire was administered between July and August 2017 in Singapore. Using the network scale-up method (NSUM), we developed a Bayesian hierarchical model to estimate the number of individuals in four hidden populations at risk of HIV. The method accounted for both transmission error and barrier effects using social acceptance measures and demographics. RESULTS: The adjusted size estimate of the population of male clients of female sex workers was 72 000 (95% CI 51 000 to 100 000), of female sex workers 4200 (95% CI 1600 to 10 000), of men who have sex with men 210 000 (95% CI 140 000 to 300 000) and of intravenous drug users 11 000 (95% CI 6500 to 17 000). CONCLUSIONS: The NSUM with adjustment for attitudes and demographics allows national-level estimates of multiple priority populations to be determined from simple surveys of the general population, even in relatively conservative societies.

Trends in unprotected intercourse among heterosexual men before and after brothel ban in Siem Reap, Cambodia: a serial cross-sectional study (2003-2012).

BACKGROUND: Following Cambodia's implementation of the 100% condom use program with enforcement of condom use and STI treatment services for sex workers in 2001, sexually transmitted infection and HIV declined markedly. In 2008, Cambodia implemented a law to ban brothel-based sex work. We reported trends in unprotected vaginal intercourse with sex workers among heterosexual men buying sex before (2003-2008) and after (2009-2012) the brothel ban in Cambodia. We also determined the association of brothel ban with these men's reports of unprotected intercourse with sex workers. METHODS: In this serial cross-sectional study, we collected yearly behavioural data on random cross-sectional samples of heterosexual men buying sex who attended the only government health centre in Siem Reap for voluntary confidential counselling and testing (VCCT) between 2003 and 2012. We used multivariable Poisson regression analysis on the 10-year data of 976 men to obtain the adjusted prevalence ratio (aPR) of unprotected intercourse in the last 6 months by brothel closure. RESULTS: Men buying sex from non-brothel-based sex workers increased almost 3-fold from 17% in 2007-2008 before brothel closure to 55% in 2011-2012 after brothel closure (p < 0.001). Unprotected intercourse with sex workers in the last week increased significantly from 37% (2003-2004) before brothel closure to 65% (2011-2012) after brothel closure. This increase corresponded closely with the increase in self-reported unprotected intercourse from 35% to 61% by the sex workers (n = 1805) attending the same clinic for VCCT. Brothel closure was associated with an increased risk (aPR: 1.65; 95% CI: 1.40-1.94) of unprotected intercourse with sex workers. HIV prevalence in the heterosexual men declined significantly from 26% in 2003-2004 to 4.8% in 2007-2008 and 0 case in 2009-2010 before increasing to 5.6% in 2011-2012. CONCLUSION: Our findings suggest that the brothel ban had led to an increase in unprotected intercourse with all sex workers for men buying sex. This effect could be attributed to reduced condom access, a consequence of the lack of feasibility to implement the 100% condom use program following the brothel ban. The ban on brothels in Cambodia should be reviewed.