Jaray Tongtoyai

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. J. Med. Virol. 85:1499–1505, 2013.

Hepatitis B vaccination uptake and correlates of serologic response among HIV-infected and uninfected men who have sex with men (MSM) in Bangkok, Thailand.

BACKGROUND Vaccination against hepatitis B virus (HBV) is recommended for all HBV-susceptible men who have sex with men (MSM). There is limited information on correlates of immunity to HBV vaccination in this group. We present serologic response rates to hepatitis B vaccine and identify factors associated with impaired response among HIV-uninfected and HIV-infected Thai MSM. METHODOLOGY HBV-susceptible volunteers were offered hepatitis B vaccination at months zero, one, and six. We measured baseline (pre-vaccination) total serum IgG and IgG subclasses (all participants), baseline CD4 count, and plasma HIV-1 viral load (PVL) (HIV+ participants). HBV serologies were retested at 12 months. Serologic responses were compared between all groups in men receiving three vaccine doses. RESULTS 511/651 HIV-negative and 64/84 HIV-positive participants completed the three-dose series. Response rates in HIV-uninfected and -infected participants were 90.1% vs. 50.0% (p<0.0001). Median pre-vaccination IgG was higher among non-responders than responders overall (1238.9.0 vs. 1057.0mg/dL, p=0.003) and among HIV-infected participants (1534.0 vs. 1244.5mg/dL, p=0.005), but not significantly among HIV-uninfected participants (1105.5 vs. 1054.3mg/dL, p=0.96). Pre-vaccination IgG1 and IgG3 levels were higher among HIV-positive than HIV-negative participants (median 866.0 vs. 520.3, and 105.8 vs. 83.1mg/dL, respectively, p<0.0001). Among HIV-infected participants, median CD4 count in non-responders was 378 cells/μL vs. 431 cells/μL in responders (p=0.20). Median PVL in non-responders was 64,800 copies/mL vs. 15500 copies/mL in responders (p=0.04). Participants with pre-vaccination plasma IgG >1550 mg/dL and PVL >10,000 copies/mL were almost always non-responsive (p<0.01). CONCLUSIONS HIV infection was associated with poor vaccine responses. High plasma viral load, elevated pre-vaccination total serum IgG and elevated pre-vaccination IgG1 are associated with poorer response to vaccination among HIV-infected MSM. In this group, the combination of high PVL and pre-vaccination total IgG is highly predictive of vaccine failure.

Analysis of False-Negative Human Immunodeficiency Virus Rapid Tests Performed on Oral Fluid in 3 International Clinical Research Studies

Background. The OraQuick Advance Rapid HIV-1/2 Test is a point-of-care test capable of detecting human immunodeficiency virus (HIV)-specific antibodies in blood and oral fluid. To understand test performance and factors contributing to false-negative results in longitudinal studies, we examined results of participants enrolled in the Botswana TDF/FTC Oral HIV Prophylaxis Trial, the Bangkok Tenofovir Study, and the Bangkok MSM Cohort Study, 3 separate clinical studies of high-risk, HIV-negative persons conducted in Botswana and Thailand. Methods. In a retrospective observational analysis, we compared oral fluid OraQuick (OFOQ) results among participants becoming HIV infected to results obtained retrospectively using enzyme immunoassay and nucleic acid amplification tests on stored specimens. We categorized negative OFOQ results as true-negative or false-negative relative to nucleic acid amplification test and/or enzyme immunoassay, and determined the delay in OFOQ conversion relative to the estimated time of infection. We used log-binomial regression and generalized estimating equations to examine the association between false-negative results and participant, clinical, and testing-site factors. Results. Two-hundred thirty-three false-negative OFOQ results occurred in 80 of 287 seroconverting individuals. Estimated OFOQ conversion delay ranged from 14.5 to 547.5 (median, 98.5) days. Delayed OFOQ conversion was associated with clinical site and test operator (P < .05), preexposure prophylaxis (P = .01), low plasma viral load (P < .02), and time to kit expiration (P < .01). Participant age, sex, and HIV subtype were not associated with false-negative results. Long OFOQ conversion delay time was associated with antiretroviral exposure and low plasma viral load. Conclusions. Failure of OFOQ to detect HIV-1 infection was frequent and multifactorial in origin. In longitudinal trials, negative oral fluid results should be confirmed via testing of blood samples.

Loss to follow-up and bias assessment among a cohort of Thai men who have sex with men in Bangkok, Thailand

Minimising loss to follow-up is essential to obtain unbiased results. This study aimed to assess factors associated with loss to follow-up and effects on biasing exposure-outcome associations in a cohort of men who have sex with men in Bangkok. We enrolled sexually-active Thai men who have sex with men, at least 18 years old, in a study with four-monthly follow-up visits. At each visit, men answered HIV risk behaviour questions using audio computer-assisted self-interview. Logistic regression was used to evaluate factors associated with loss to follow-up and bias between exposures and prevalent HIV infection were estimated using adjusted relative odds ratios. From 2006 to 2010, we enrolled 1744 men who have sex with men; as of April, 2014, 1256 (72%) had completed at least the month-36 visit; loss to follow-up was 9.6%. Factors independently associated with loss to follow-up were age (18–21 years), education (primary level or less, secondary or vocational education), living outside Bangkok and vicinity, sexual orientation (bisexual, heterosexual), previous HIV testing, HIV infection, and behaviour in the past 4 months (recreational drug use, reporting group sex). An effect of loss to follow-up on factors of prevalent HIV infection was found by sexual orientation (transgender) and unprotected anal intercourse (receptive/insertive). These findings highlight the need to strengthen post-HIV test counselling. Directed counselling for HIV care should be given to young men who have sex with men and recreational drug users.

The finding of casual sex partners on the internet, methamphetamine use for sexual pleasure, and incidence of HIV infection among men who have sex with men in Bangkok, Thailand: an observational cohort study

BACKGROUND The finding of casual sex partners on the internet and methamphetamine use have been described as risk factors for HIV infection in men who have sex with men (MSM). However, the interplay between these factors has not been studied prospectively in one design. This study aims to determine the associations between finding casual sex partners on the internet and incident methamphetamine use and HIV infection. METHODS In this observational cohort study of Thai MSM, we recruited Bangkok residents aged 18 years or older with a history of penetrative male-to-male sex in the past 6 months. Baseline and follow-up visits were done at a dedicated study clinic in central Bangkok. Men were tested for HIV infection at every study visit and for sexually transmitted infections at baseline. Baseline demographics and HIV risk behaviour information were collected at every visit by audio computer-assisted self-interview. We used a descriptive model using bivariate odds ratios to elucidate the order of risk factors in the causal pathway to HIV incidence and methamphetamine use. We used Cox proportional hazard regression analysis to evaluate covariates for incident methamphetamine use and HIV infection. FINDINGS From April 6, 2006, to Dec 31, 2010, 1977 men were screened and 1764 were found eligible. 1744 men were enrolled, of whom 1372 tested negative for HIV and were followed up until March 20, 2012. Per 100 person-years of follow-up, incidence of methamphetamine use was 3·8 (128 events in 3371 person-years) and incidence of HIV infection was 6·0 (212 events in 3554 person-years). In our descriptive model, methamphetamine use, anal sex, and various other behaviours cluster together but their effect on HIV incidence was mediated by the occurrence of ulcerative sexually transmitted infections. Dual risk factors for both incident methamphetamine use and HIV infection were younger age and finding casual sex partners on the internet. Having ever received money for sex was predictive for incident methamphetamine use; living alone or with a housemate, recent anal sex, and ulcerative sexually transmitted infections at baseline were predictive for incident HIV infection. INTERPRETATION In MSM in Bangkok, casual sex partner recruitment on the internet, methamphetamine use, and sexually transmitted infections have important roles in sustaining the HIV epidemic. Virtual HIV prevention education, drug use harm reduction, and biomedical HIV prevention methods, such as pre-exposure prophylaxis, could help to reduce or revert the HIV epidemic among MSM in Bangkok. FUNDING US Centers for Disease Control and Prevention and the Johns Hopkins Fogarty AIDS International Training and Research Program.

Association between HIV genotype, viral load and disease progression in a cohort of Thai men who have sex with men with estimated dates of HIV infection

Background Differences between HIV genotypes may affect HIV disease progression. We examined infecting HIV genotypes and their association with disease progression in a cohort of men who have sex with men with incident HIV infection in Bangkok, Thailand. Methods We characterized the viral genotype of 189 new HIV infections among MSM identified between 2006–2014 using hybridization and sequencing. Plasma viral load (PVL) was determined by PCR, and CD4+ T-cell counts were measured by flow cytometry. We used Generalized Estimating Equations to examine factors associated with changes in CD4+ T-cell counts. Factors associated with immunologic failure were analyzed using Cox proportional hazard models. Results Among 189 MSM, 84% were infected with CRF01_AE, 11% with recombinant B/CRF01_AE and 5% with subtype B. CD4+ T-cell decline rates were 68, 65, and 46 cells/μL/year for CRF01_AE, recombinants, and subtype B, respectively, and were not significantly different between HIV subtypes. CD4+ T-cell decline rate was significantly associated with baseline PVL and CD4+ T-cell counts (p <0.001). Progression to immunologic failure was associated with baseline CD4+ T-cell ≤ 500 cells/μL (AHR 1.97; 95% CI 1.14–3.40, p = 0.015) and PVL > 50,000 copies/ml (AHR 2.03; 1.14–3.63, p = 0.017). There was no difference in time to immunologic failure between HIV subtypes. Conclusion Among HIV-infected Thai MSM, low baseline CD4+ T-cell and high PVL are associated with rapid progression. In this cohort, no significant difference in CD4+ T-cell decline rate or time to immunologic failure was seen between CRF01_AE and other infecting HIV subtypes.

Screening for Chlamydia trachomatis and Neisseria gonorrhoeae infection among asymptomatic men who have sex with men in Bangkok, Thailand:

We report positivity rates of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infection at each anatomic site among asymptomatic men who have sex with men (MSM). We calculated the number needed to screen (NNS) to detect CT and NG infection at each anatomic site. From 2006 to 2010, we enrolled Thai MSM, age ≥ 18 years into the Bangkok MSM Cohort Study. Participants underwent physical examination and had rectal, urethral, and pharyngeal screening for CT and NG infection using nucleic acid amplification tests (NAATs). Of 1744 enrollees, 1696 (97.2%) had no symptoms of CT and NG infection. The positivity rates of CT and NG infection at any site were 14.3% (rectum, urethra, pharynx) and 6.4% (rectum, urethra), respectively. The NNS to detect rectal CT and rectal NG infections was 10 and 16, respectively (p < 0.05). For urethral infection, the NNS of CT was lower than the NNS of NG (22, 121: p < 0.05). The lowest NNS found for rectal CT infection was in HIV-infected MSM (6, 5–8). Asymptomatic CT and NG infection were common among MSM in Bangkok, Thailand and frequently detected in the rectum. In setting where screening in all specimens using NAAT is not feasible, rectal screening should be a priority.

O12.6 Quality assessment of the enhanced gonococcal antimicrobial surveillance program in thailand, 2015–2016

Introduction Antimicrobial resistant Neisseria gonorrhoea (NG) is important to monitor as a potential global public health threat. The Thailand Enhanced Gonococcal Antimicrobial Surveillance Programme (EGASP) was started in November 2015 as a collaboration between the Thailand Ministry of Public Health, the US Centres for Disease Control and Prevention and the World Health Organisation. As a part of this surveillance activity, Thailand conducted an internal quality assessment (QA) of clinical and laboratory data in order to improve surveillance data quality. Methods EGASP Thailand occurs in 2 sentinel sites: Bangrak Hospital and Silom Community Clinic at Tropical Medicine. Men with symptoms had demographic and clinical data collected as well as a urethral specimen collected for NG culture. A random selection of 10% of EGASP IDs were sampled from November 2015 to June 2016. We assessed clinical and laboratory findings using a standardised review tool that compared the EGASP database to source documents. We describe key findings from the review activities. Results Overall, 699 specimens were collected for EGASP and 70 (10%) EGASP IDs were randomly sampled by SQL command for review. Results from the quality review included: differences in laboratory findings (6%), differences in interpretation of the clinical abstraction tool between sentinel sites (10%), missing data in the EGASP database after chart abstraction and laboratory testing (14%), differences in the recording of clinical data (19%), and differences in the recording and tracking of laboratory variables (47%). As a result of this evaluation, staff updated missing data on records sampled, conducted an overall refresher training for staff and established a new laboratory tracking process. Conclusion EGASP Thailand is the first coordinated global project to conduct comprehensive surveillance for NG resistance from symptomatic men. An internal QA helped direct efforts to improve surveillance. Ongoing NG surveillance and periodic quality assessments help ensure high quality surveillance data.

P3.65 The enhanced gonococcal antimicrobial surveillance program (EGASP) in thailand, 2015–2016

Introduction Antimicrobial resistant Neisseria gonorrhoea (NG) is a global public health threat, and it is critical to monitor patterns of resistance and risk factors. The Thailand Ministry of Public Health, the Centres for Disease Control and Prevention and World Health Organisation began the Enhanced Gonococcal Antimicrobial Surveillance Programme (EGASP) in November 2015. Thailand is the first EGASP country to systematically monitor trends in NG antimicrobial susceptibilities. Methods Surveillance occurs in 2 sites: Bangrak Hospital (BH) and Silom Community Clinic at Tropical Medicine (SCC). Men receiving HIV voluntary counselling and testing were routinely asked about urethral symptoms. Symptomatic men had demographic and clinical data collected and a urethral swab for Gram stain and NG culture. All positive cultures had antimicrobial susceptibility testing (AST) to determine minimum inhibition concentrations (MICs) for Cefixime (CFM), Ceftriaxone (CRO), Azithromycin (AZI), Gentamicin (GEN), and Ciprofloxacin (CIP) using E-test. Results From November 2015-August 2016, 900 specimens were collected; 713 (79.2%) specimens were from BH and 187 (20.8%) were from SCC. Among the 900 specimens, 479 (53.3%) had NG growth; 478 (99.8%) NG isolates had AST performed. Seventeen men had repeat NG infections. Among the 461 men with at least one infection, 291 (63.1%) had sex with women only, 138 (29.9%) had antibiotic use in the last 2 weeks, and all received treatment for gonorrhoea. The median age of men with NG infection was 29 years (range 14–76 years). All NG isolates were susceptible by Clinical and Laboratory Standards Institute standards to CFM, CRO, AZI and GEN; 438 of 478 (91.6%) isolates were resistant to CIP. Conclusion We report the first 10 months of data from EGASP Thailand. Most isolates were found to be susceptible to all tested antibiotics except CIP. Surveillance is critical to assess trends and risk factors for NG, and to monitor for emergence of resistance.