Substance use

Use of amphetamine-type stimulants (ATS) is common among MSM and TGW, and is associated with high-risk behavior for HIV infection. IHRI is conducting the ATS study, funded by the United States National Institute of Health’s International Epidemiology Databases to evaluate AIDS (IeDEA) through amfAR, to look at the pattern of ATS and other substance use and relationships with adherence to ART or PrEP, HIV incidence, and other STI incidence rates among Thai MSM and TGW. Results so far show that injection of crystal methamphetamine was reported by 7%, and that ATS use was higher in HIV-positive participants (27.1%) than in HIV-negative (14.6%) participants. Other substance use (tobacco, alcohol) and specific sexual practices (selling sex, group sex) are associated with ATS use, and should prompt careful screening for ATS use.

The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) questionnaire is the global standard tool for the screening of substance use, and assesses the level of risk participants have. The test score categorizes risk into mild, moderate or high risk. To those with moderate or high risk a brief intervention (BI) can be administered to help address drug use. IHRI has integrated the use of ASSIST and BI into the KPLHS model. As of September 2019, 3,282 people were screened using ASSIST in the CBOs and 71% reported substance use. Of substance users, 10% used ATS and 44% of ATS users injected it in the past 3 months.

The success of the program resulted in IHRI receiving a distinguished award for its commitment to addressing substance use in key populations at the 19th International Conference of Public Health Sciences, held by the College of Public Health Sciences, Chulalongkorn University

Moving forward as leaders to address the emerging public health concern in Chemsex, IHRI is planning to conduct a new study, ‘Project-X’, to identify factors involving initiation of Chemsex and patterns of use among older adolescent men who have sex with men.

Recent outbreaks of hepatitis C virus (HCV) infection have been reported among MSM. In 2477 person-years of follow up in the SEARCH010/RV254 cohort, 66 HCV incident cases were identified (26.6 per 1000 person-years of follow-up) with incidence density rate (IDR) per 1000 PYFU increasing from 11.4 in 2014 (initial detection of incident cases) to 48.7 in 2019 (p<0.001).

Results of the ATS study show that HCV prevalence was very high among HIV-infected MSM (14.3% with ATS use and 8.6% without ATS use). These data indicated that HCV infection is spreading rapidly among MSM using ATS, and HIV-infected MSM in Bangkok. Most cases of HCV infection appear to be transmitted by anal sex, possibly potentiated by the presence of STIs and rough or prolonged sex in the context of illicit drug use. Harm reduction, including early HCV testing and treatment with direct-acting antivirals, is needed to address this newly emerging epidemic.

Moreover, HCV is inadequately screened among at-risk populations. To explore the prevalence and mitigate the risk of onward transmission of HCV, IHRI will incorporate HCV screening for all clients accessing services at affiliated CBOs.


Much of the information about human papillomavirus centers around women, since it increases the risk of cervical cancer. Unsurprisingly, human papillomavirus (HPV) infection can also affect men and increase the risk of developing ano-genital cancers. Despite the high burden of HPV infection and its related diseases in Thailand, HPV vaccination currently remains inaccessible to all due to unaffordable prices. HPV infection and anal cancer in Thai MSM with acute HIV infection are even more poorly understood. IHRI carried out two studies to understand the epidemiological relationship between HIV, HPV and anal cancer and explore innovative ways to manage HPV infection.

Anal cancer is predominantly caused by persistent HPV infection. HPV typically clears naturally; however, under certain circumstances, it may persist longer and progress into anal cancer if left untreated. Recent estimates suggest that anal cancer has become a crisis among HIV-positive MSM. Whether ART is able to reduce the risk of anal cancer remains inconclusive. Hoping to shed some light on the issue, IHRI started a study to determine the prevalence and incidence of anal high-grade intraepithelial lesion (HSIL) and the associated risk factors among MSM who initiate ART during acute HIV infection (AIN in AHI). To date, IHRI has successfully enrolled 96 participants over the course of 36 months, with the anticipation to complete the study by May 2021. The study will provide evidence for understanding the effect that early diagnosis of HIV infection and early treatment with ART might have on incidence and persistence of HPV infection or the development of anal HSIL.

Mental health

Many research data have pointed to a high prevalence of mental health issues among transgender women. Unfortunately, the prevalence of common mental health issues among Thai transgender women is unknown. In July 2019, a self-administered mental health questionnaire was integrated into Tangerine Clinic services to screen for depression. During the short period of implementation, we observed that more than half of our transgender clients had depressive symptoms. To confront the growing interlinked burden of HIV and mental health issues in the Asia-Pacific region, IHRI will be participating in the CHIMERA program (Capacity development for HIV and mental health research in Asia) to lead the region’s first HIV-mental health-implementation science research that will inform public health policies and improve clinical care and patient outcomes.


Since the eruption of the coronavirus disease 2019 (COVID-19) in December 2019, and the declaration by the World Health Organization as a pandemic in March 2020. To date, there are over thirteen million COVID-19 in the world with a devastating half a million deaths. In Thailand, there are over three thousand COVID-19 cases. However, surfacing reports of local communities refusing resolved clients to return home are accumulating in Thailand. Some resolved COVID-19 clients were banished from their homes by worried neighbors, some villagers protested against hospitals setting up isolation units for recovering COVID-19 clients or persons under investigation (PUIs) near their neighborhood.

The evidential stigma and discrimination against populations affected by COVID-19 may have an impact on the mental health of the individual. Those who might have symptoms suggestive of COVID-19 might not present themselves for testing since they might be at risk of scrutiny from society. All these contribute towards creating barriers to testing, treatment and prevention of the disease.  IHRI launched a new study to investigate drivers that might contribute to stigma and discrimination against COVID-19 and which aims to assess interventions which might reduce it, such as launching of public campaigns and community preparation.

To study the longitudinal COVID-19 serology patterns prior to and after the local COVID-19 lockdown among Thai adults who have used antiretroviral drugs (ARVs) for HIV PrEP or treatment and compare them to HIV-negative individuals not on PrEP, the SARS-CoV-2 antibody testing will be conducted on leftover samples collected from among a network of community-based PrEP sites, the Thai Red Cross Anonymous Clinic, and the RV254/SEARCH010 cohort by the Vaccine Immunology Program at the Vaccine Research Center (VRC) of the National Institute of Allergy and Infectious Disease (NIAID) of the US National Institutes of Health. Samples will also be tested for other respiratory viruses (including other circulating coronaviruses) and HIV to facilitate comparisons and study cross-reactivity and cross-protection.

This study will be implemented by IHRI and TRCARC, with support from amfAR’s TREAT Asia program, under the IeDEA Asia-Pacific network.