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.

Renal function of participants in the Bangkok tenofovir study--Thailand, 2005-2012.

BACKGROUND: Tenofovir disoproxil fumarate (tenofovir) has been associated with renal dysfunction in people infected with human immunodeficiency virus (HIV) receiving combination antiretroviral therapy. We reviewed data from an HIV preexposure prophylaxis trial to determine if tenofovir use was associated with changes in renal function in an HIV-uninfected population. METHODS: During the trial, 2413 HIV-uninfected people who inject drugs were randomized to receive tenofovir or placebo. We assessed the renal function of trial participants with the Cockcroft-Gault, Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations using t tests for cross-sectional analysis and linear regression for longitudinal analysis. RESULTS: Creatinine clearance and glomerular filtration rate (GFR) results were lower at 24, 36, 48, and 60 months in the tenofovir group compared with the placebo group. Results declined more in the tenofovir group than in the placebo group during follow-up using the Cockcroft-Gault (P < .001) and CKD-EPI (P = .007) equations, but not MDRD (P = .12). Creatinine clearance measured when study drug was stopped was lower in the tenofovir group than the placebo group (P < .001), but the difference resolved when tested a median of 20 months later (P = .12). CONCLUSIONS: We found small but significant decreases in cross-sectional measures of creatinine clearance and GFR in the tenofovir group compared with the placebo group and modest differences in downward trends in longitudinal analysis using the Cockcroft-Gault and CKD-EPI equations. These results suggest that with baseline assessments of renal function and routine monitoring of creatinine clearance during follow-up, tenofovir can be used safely for HIV preexposure prophylaxis. Clinical Trials Registration. NCT00119106.

Cyclic changes in HIV shedding from the female genital tract during the menstrual cycle.

Factors increasing genital human immunodeficiency virus (HIV) shedding may increase female-to-male HIV transmission risk. We examined HIV shedding in 67 women with HIV type 1 and herpes simplex virus type 2 coinfection, during 2 menstrual cycles. Shedding occurred in 60%, 48%, and 54% of samples during the follicular, periovulatory, and luteal phases, respectively (P = .01). Shedding declined after menses until ovulation, with a slope -0.054 log10 copies/swab/day (P < .001), corresponding to a change of approximately 0.74 log10 copies between peak and nadir levels. Shedding increased during the luteal phase only among women with CD4 counts of <350 cells/µL. In reproductive-aged women, shedding frequency and magnitude are greatest immediately following menses and lowest at ovulation.

Complete Genome Sequence of Neisseria gonorrhoeae Multilocus Sequence Type ST7363 Isolated from Thailand.

A Neisseria gonorrhoeae multilocus sequence type (MLST) ST7363 strain was isolated from a patient at the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, in 2010 and completely sequenced. This strain is susceptible to ceftriaxone and cefixime. A complete circular chromosome and circular plasmids were assembled from combined Oxford Nanopore Technologies (ONT) and Illumina sequencing.

Altered Antibody Responses in Persons Infected with HIV-1 While Using Preexposure Prophylaxis.

Preexposure prophylaxis (PrEP) is an effective HIV prevention tool, although effectiveness is dependent upon adherence. It is important to characterize the impact of PrEP on HIV antibody responses in people who experience breakthrough infections to understand the potential impact on timely diagnosis and treatment. Longitudinal HIV-1-specific antibody responses were evaluated in 42 people who inject drugs (PWID) from the Bangkok Tenofovir Study (BTS) (placebo = 28; PrEP = 14) who acquired HIV while receiving PrEP. HIV-1 antibody levels and avidity to three envelope proteins (gp41, gp160, and gp120) were measured in the plasma using a customized Bio-Plex (Bio-Rad Laboratories, Hercules, CA) assay. A time-to-event analysis was performed for each biomarker to compare the distribution of times at which study subjects exceeded the recent/long-term assay threshold, comparing PrEP and placebo treatment groups. We fit mixed-effects models to identify longitudinal differences in antibody levels and avidity between groups. Overall, longitudinal antibody levels and avidity were notably lower in the PrEP breakthrough group compared to the placebo group. Time-to-event analyses demonstrated a difference in time to antibody reactivity between treatment groups for all Bio-Plex biomarkers. Longitudinal gp120 antibody levels within the PrEP breakthrough group were decreased compared to the placebo group. When accounting for PrEP adherence, both gp120 and gp160 antibody levels were lower in the PrEP breakthrough group compared to the placebo group. We demonstrate hindered envelope antibody maturation in PWID who became infected while receiving PrEP in the BTS, which has significant implications for HIV diagnosis. Delayed maturation of the antibody response to HIV may increase the time to detection for antibody-based tests. Clinical Trial Registration Number, NCT00119106.

Complete Genome Sequences of Three Neisseria gonorrhoeae Isolates from Thailand with Multidrug Resistance and Multilocus Sequence Type 1903.

Multilocus sequence typing (MLST) sequence type 1903 (ST1903) is the most common ST of ceftriaxone-resistant Neisseria gonorrhoeae Here, we report three completed genome sequences of MLST ST1903 N. gonorrhoeae isolates collected from patients at Faculty of Medicine Siriraj Hospital, a university hospital in Bangkok, Thailand, in 2009 to 2011.

Antiretroviral resistance patterns and HIV-1 subtype in mother-infant pairs after the administration of combination short-course zidovudine plus single-dose nevirapine for the prevention of mother-to-child transmission of HIV.

BACKGROUND: World Health Organization guidelines for prevention of mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1) recommend administration of zidovudine and single-dose nevirapine (NVP) for HIV-1-infected women who are not receiving treatment for their own health or if complex regimens are not available. This study assessed antiretroviral resistance patterns among HIV-infected women and infants receiving single-dose NVP in Thailand, where the predominant circulating HIV-1 strains are CRF01_AE recombinants and where the minority are subtype B. METHODS: Venous blood samples were obtained from (1) HIV-infected women who received zidovudine from 34 weeks' gestation and single-dose NVP plus oral zidovudine during labor and (2) HIV-infected infants who received single-dose NVP after birth plus zidovudine for 4 weeks after delivery. HIV-1 drug resistance testing was performed using the TruGene assay (Bayer HealthCare). RESULTS: Most mothers and infants were infected with CRF01_AE. NVP resistance was detected in 34 (18%) of 190 women and 2 (20%) of 10 infants. There was a significantly higher proportion of NVP mutations in women with delivery viral loads of >50,000 copies/mL (adjusted odds ratio, 8.5; 95% confidence interval, 2.2-32.8, P = .002 for linear trend) and in those with subtype B rather than CRF01_AE infections (38% vs. 16%; adjusted odds ratio, 3.6; 95% confidence interval, 1.1-11.8; P = .038). CONCLUSIONS: The lower frequency of NVP mutations among mothers infected with subtype CRF01_AE, compared with mothers infected with subtype B, suggests that individuals infected with subtype CRF01_AE may be less susceptible to the induction of NVP resistance than are individuals infected with subtype B.

Hepatitis C virus infection among people who inject drugs in Bangkok, Thailand, 2005-2010.

Background: Approximately 1% of adults in Thailand are infected with hepatitis C virus (HCV). New direct-acting antiviral agents achieve sustained virologic responses in >95% of HCV-infected patients and are becoming available in countries around the world. To prepare for new HCV treatment options in Thailand, this study characterized HCV infections among people who inject drugs (PWID) in Bangkok. Methods: The Bangkok Tenofovir Study (BTS) was a pre-exposure prophylaxis trial conducted among PWID, 2005-2013. Blood specimens were randomly selected from PWID screened for the BTS, to test for anti-HCV antibody and HCV RNA. The HVR1 region was amplified by polymerase chain reaction, using multiplex primer sets with unique identifier sequences; amplification products were pooled in sets of 25; and consensus sequencing was performed to characterize individual HCV genotypes. Results: The median age of 3679 participants tested for anti-HCV antibody was 31 years, 3016 (82.0%) were male and 447 (12.2%) were HIV infected. The prevalence of anti-HCV antibody was 44.3%. The adjusted odds of testing positive for anti-HCV antibody were higher in men (adjusted odds ratio [aOR] 3.2, 95% confidence interval [CI] 2.4-4.3), those aged 40 years or older (aOR 2.7, 95% CI 2.1-3.5), those who had more than a primary school education (aOR 1.7, 95% CI 1.4-2.1), and those who tested HIV positive (aOR 5.2, 95% CI 3.7-7.4). HCV RNA was detected in 644 (81.3%) of the 792 anti-HCV antibody-positive specimens, yielding an HCV RNA-positive prevalence of 36.0% (95% CI 33.8-38.2). Among a random sample of 249 of the 644 specimens, 218 could be characterized, and the most common HCV subtypes were 1a (30.3%), 1b (12.8%), 3a (35.8%), 3b (6.9%) and 6n (8.7%). Conclusion: The prevalence of anti-HCV antibody among PWID was 44.3% and more than one third (36.0%) were HCV RNA positive. Genotypes 1, 3 and 6 accounted for all typable infections. As the government of Thailand considers introduction of direct-acting antiviral medications for people with hepatitis C, it will be important to ensure that the medications target these subtypes.

HIV-1 genetic diversity to estimate time of infection and infer adherence to preexposure prophylaxis.

OBJECTIVE: To estimate time of HIV infection in participants from the Bangkok Tenofovir Study (BTS) with daily oral tenofovir disoproxil fumarate (TDF) for preexposure prophylaxis (PrEP) and relate infection with adherence patterns. DESIGN: We used the diversity structure of the virus population at the first HIV RNA-positive sample to estimate the date of infection, and mapped these estimates to medication diaries obtained under daily directly observed therapy (DOT). METHODS: HIV genetic diversity was investigated in all 17 PrEP breakthrough infections and in 16 placebo recipients. We generated 10-25 HIV env sequences from each participant by single genome amplification, and calculated time since infection (and 95% confidence interval) using Poisson models of early virus evolution. Study medication diaries obtained under daily DOT were then used to compute the number of missed TDF doses at the approximate date of infection. RESULTS: Fifteen of the 17 PrEP breakthrough infections were successfully amplified. Of these, 13 were initiated by a single genetic variant and generated reliable estimates of time since infection (median = 47 [IQR = 35] days). Eleven of these 13 were under daily DOT at the estimated time of infection. Analysis of medication diaries in these 11 participants showed 100% adherence in five, 90-95% adherence in two, 55% adherence in one, and nonadherence in three. CONCLUSION: We estimated time of infection in participants from BTS and found several infections when high levels of adherence to TDF were reported. Our results suggest that the biological efficacy of daily TDF against parenteral HIV exposure is not 100%.

HIV drug resistance threshold survey using specimens from voluntary counselling and testing sites in Hanoi, Vietnam.

BACKGROUND: In countries where antiretroviral therapy has been available or is being rapidly expanded, the World Health Organization (WHO) recommends surveillance for transmitted HIV drug resistance (HIVDR) by threshold surveillance methods using specimens from antenatal clinics or voluntary counselling and testing (VCT) sites. The aim of this study was to implement the HIVDR threshold survey in VCT sites in Vietnam, where HIV prevalence is high. Estimating transmitted resistance in the infected population will enable the appropriateness of current antiretroviral drug regimens to be assessed and will inform plans for future HIVDR surveillance. METHODS: Consecutive blood specimens were collected from 70 newly diagnosed HIV-positive clients 18-24 years of age at two sites in Hanoi, Vietnam. Informed consent and serum specimens were obtained from each eligible client, with serum frozen at -70 degrees C until shipping to Thailand for resistance testing using the TruGene system. RESULTS: From February until August 2006, 559 clients were eligible to participate in this survey. Of the 535 clients (95.7%) who agreed to participate, 70 (13%) were HIV-positive and were included in the survey. Of the 70 specimens sent for genotyping, 52 consecutive samples were amplified, 49 of which could be genotyped. Only 1 of 49 genotyped specimens had mutations associated with drug resistance (L74V and Y181C) in the reverse transcriptase gene, indicating that the prevalence of transmitted HIVDR to all drugs and drug classes evaluated was <5%. CONCLUSION: The prevalence of transmitted HIVDR was low in Hanoi as determined using threshold surveillance methods. The Ministry of Health plans to repeat this survey methodology in one more province and to confirm these findings by expanded HIVDR surveillance.

Increase in sexual risk behavior and prevalence of Chlamydia trachomatis among adolescents in Northern Thailand.

BACKGROUND: Monitoring changes in adolescent sexual risk behaviors and sexually transmitted infections is critical for evaluating the effectiveness of human immunodeficiency virus and other prevention programs, but population-based data on adolescents in Thailand are limited. We report findings from 2 cross-sectional surveys conducted in 1999 and 2002 among 15-to 21-year-old vocational students. METHODS: In 1999 and 2002, 1725 and 966 students, respectively, were interviewed using computer-assisted self-interview methods. Urine samples were collected and tested for Chlamydia trachomatis and Neisseria gonorrhoeae by polymerase chain reaction. RESULTS: From 1999 to 2002 C. trachomatis prevalence increased from 3.2% to 7.5% (P <0.001) in women and from 2.5% to 6.0% (P <0.001) in men. There was an increase in the reported mean lifetime number of steady sexual partners among both men (3.4-4.7, P = 0.01) and women (2.5-3.3, P <0.001), and in the mean lifetime number of casual partners among men (1.1-2.1, P <0.001) and women (0.3-1.1, P = 0.04). Reported consistent condom use decreased significantly among women with casual partners (43%-19%, P = 0.03) but not among men (25%-31%, P = 0.31). CONCLUSIONS: Our study identified important increases in the prevalence of chlamydial infection and in sexual risk behaviors among Thai adolescents over a 3-year period. These findings are consistent with other studies suggesting profound social changes are changing norms of adolescent sexual behavior in Thailand, and highlight the need for adolescent sexual health services and prevention programming.

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.

Subtypes and Risk Behaviors Among Incident HIV Cases in the Bangkok Men Who Have Sex with Men Cohort Study, Thailand, 2006-2014.

HIV-1 incidence and prevalence remain high among men who have sex with men (MSM), and transgender women (TGW), in Thailand. To examine the link between epidemiologic factors and HIV-1 subtype transmission among Thai MSM, we compared covariates of infection with HIV CRF01_AE and other HIV strains among participants in the Bangkok MSM Cohort Study (BMCS). The BMCS was an observational cohort study of Thai MSM and TGW with up to 60 months of follow-up at 4 monthly intervals. Participants underwent HIV/sexually transmitted infections testing and provided behavioral data at each visit. Infecting viral strain was characterized by gene sequencing and/or multiregion hybridization assay. We correlated behavioral/clinical variables with infecting strain using Cox proportional hazards. Among a total of 1372 HIV seronegative enrolled participants with 4,192 person-years of follow-up, we identified 215 seroconverters between April 2006 and December 2014, with 177 infected with CRF01_AE and 38 with non-CRF01_AE subtype. Age 18-21 years (adjusted hazard ratio [AHR] 2.2, 95% confidence interval [CI]: 1.4-3.5), age 22-29 (AHR 1.6, 95% CI: 1.1-2.3), living alone (AHR 1.5, 95% CI: 1.1-2.1), drug use (AHR 2.2, 95% CI: 1.4-3.5), intermittent condom use (AHR 1.7, 95% CI: 1.3-2.3), any receptive anal intercourse (AHR 1.7, 95% CI: 1.2-2.4), group sex (AHR 1.5, 95% CI: 1.1-2.2), anti-herpes simplex virus type 1 (AHR 1.5, 95% CI: 1.1-2.1), and Treponema pallidum antibody positivity (AHR 2.5, 95% CI: 1.4-4.4) were associated with CRF01_AE infection. Age 18-21 years (AHR 5.1, 95% CI: 1.6-16.5), age 22-29 (AHR 3.6, 95% CI: 1.3-10.4), drug use (AHR 3.1, 95% CI: 1.3-7.5), group sex (AHR 2.4, 95% CI: 1.1-5.0), and hepatitis B virus surface antigen (AHR 3.6, 95% CI: 1.3-10.2) were associated with non-CRF01_AE infection. We observed several significant biological and behavioral correlates of infection with CRF01_AE and other HIV strains among Thai MSM. Divergence in correlates by strain may indicate differences in HIV transmission epidemiology between CRF01_AE and other strains. These differences could reflect founder effects, transmission within networks distinguished by specific risk factors, and possibly biological differences between HIV strains.

Self-collected genital swabs compared with cervicovaginal lavage for measuring HIV-1 and HSV-2 and the effect of acyclovir on viral shedding.

HIV-1 and HSV-2 are frequent genital co-infections in women. To determine how self-collected genital swabs compare to provider-collected cervicovaginal lavage, paired self-collected genital swabs and cervicovaginal lavage from women co-infected with HIV-1 and HSV-2 were evaluated. Women were in an acyclovir clinical trial and their samples were tested for HIV-1 RNA (361 samples) and HSV-2 DNA (378 samples). Virus shedding, quantity and acyclovir effect were compared. HIV-1 and HSV-2 were more frequently detected in self-collected genital swabs: 74.5% of self-collected genital swabs and 63.6% of cervicovaginal lavage had detectable HIV-1 (p ≤ 0.001, Fisher's exact test) and 29.7% of self-collected genital swabs and 19.3% of cervicovaginal lavage had detectable HSV-2 (p ≤ 0.001) in the placebo month. Cervicovaginal lavage and self-collected genital swabs virus levels were correlated (Spearman's rho, 0.68 for HIV; 0.61 for HSV-2) and self-collected genital swabs levels were generally higher. In multivariate modeling, self-collected genital swabs and cervicovaginal lavage could equally detect the virus-suppressive effect of acyclovir: for HIV-1, proportional odds ratios were 0.42 and 0.47 and for HSV-2, they were 0.10 and 0.03 for self-collected genital swabs and cervicovaginal lavage, respectively. Self-collected genital swabs should be considered for detection and measurement of HIV-1 and HSV-2 in clinical trials and other studies as they are a sensitive method to detect virus and can be collected in the home with frequent sampling.

Increasing HIV-1 molecular complexity among men who have sex with men in Bangkok.

In Thailand, new HIV-1 infections are largely concentrated in certain risk groups such as men who have sex with men (MSM), where annual incidence may be as high as 12% per year. The paucity of information on the molecular epidemiology of HIV-1 in Thai MSM limits progress in understanding the epidemic and developing new prevention methods. We evaluated HIV-1 subtypes in seroincident and seroprevalent HIV-1-infected men enrolled in the Bangkok MSM Cohort Study (BMCS) between 2006 and 2011. We characterized HIV-1 subtype in 231 seroprevalent and 194 seroincident subjects using the multihybridization assay (MHA). Apparent dual infections, recombinant strains, and isolates found to be nontypeable by MHA were further characterized by targeted genomic sequencing. Most subjects were infected with HIV-1 CRF01_AE (82%), followed by infections with recombinants (11%, primarily CRF01_AE/B recombinants), subtype B (5%), and dual infections (2%). More than 11 distinct chimeric patterns were observed among CRF01B_AE/B recombinants, most involving recombination within integrase. A significant increase in the proportion of nontypeable strains was observed among seroincident MSM between 2006 and 2011. CRF01_AE and subtype B were the most and least common infecting strains, respectively. The predominance of CRF01_AE among HIV-1 infections in Thai MSM participating in the BMCS parallels trends observed in Thai heterosexuals and injecting drug users. The presence of complex recombinants and a significant rise in nontypeable strains suggest ongoing changes in the genetic makeup of the HIV-1 epidemic in Thailand, which may pose challenges for HIV-1 prevention efforts and vaccine development.

Assessment of Oral Fluid HIV Test Performance in an HIV Pre-Exposure Prophylaxis Trial in Bangkok, Thailand.

BACKGROUND: Rapid easy-to-use HIV tests offer opportunities to increase HIV testing among populations at risk of infection. We used the OraQuick Rapid HIV-1/2 antibody test (OraQuick) in the Bangkok Tenofovir Study, an HIV pre-exposure prophylaxis trial among people who inject drugs. METHODS: The Bangkok Tenofovir Study was a randomized, double-blind, placebo-controlled trial. We tested participants' oral fluid for HIV using OraQuick monthly and blood using a nucleic-acid amplification test (NAAT) every 3 months. We used Kaplan-Meier methods to estimate the duration from a positive HIV NAAT until the mid-point between the last non-reactive and first reactive oral fluid test and proportional hazards to examine factors associated with the time until the test was reactive. RESULTS: We screened 3678 people for HIV using OraQuick. Among 447 with reactive results, 436 (97.5%) were confirmed HIV-infected, 10 (2.2%) HIV-uninfected, and one (0.2%) had indeterminate results. Two participants with non-reactive OraQuick results were, in fact, HIV-infected at screening yielding 99.5% sensitivity, 99.7% specificity, a 97.8% positive predictive value, and a 99.9% negative predictive value. Participants receiving tenofovir took longer to develop a reactive OraQuick (191.8 days) than participants receiving placebo (16.8 days) (p = 0.02) and participants infected with HIV CRF01_AE developed a reactive OraQuick earlier than participants infected with other subtypes (p = 0.04). DISCUSSION: The oral fluid HIV test performed well at screening, suggesting it can be used when rapid results and non-invasive tools are preferred. However, participants receiving tenofovir took longer to develop a reactive oral fluid test result than those receiving placebo. Thus, among people using pre-exposure prophylaxis, a blood-based HIV test may be an appropriate choice. TRIAL REGISTRATION: ClinicalTrials.gov NCT00119106.

Utility of Cryptococcal Antigen Screening and Evolution of Asymptomatic Cryptococcal Antigenemia among HIV-Infected Women Starting Antiretroviral Therapy in Thailand.

Cryptococcal meningitis (CM) remains a significant HIV-associated opportunistic infection in Southeast Asia and Africa, with a high burden of disease and a high mortality rate despite the availability of antiretroviral therapy (ART). We retrospectively examined the utility of cryptococcal antigen screening to identify risk for CM among 211 Thai women initiating ART. Antigenemia prevalence was 11% (n = 9) among 84 women with a CD4 count <100 cells/mm(3). Screening identified all women who later developed CM. Cryptococcal antigen titers decreased over time with ART. Our study confirmed findings from previous studies in Thailand and South Africa and provided novel observational data regarding the course of cryptococcal antigenemia in patients initiating ART and the poor efficacy of low-dose fluconazole prophylaxis in preventing CM among patients with antigenemia.

Suppressive acyclovir therapy reduces HIV cervicovaginal shedding in HIV- and HSV-2-infected women, Chiang Rai, Thailand.

BACKGROUND: Herpes simplex virus type 2 infection is important in the HIV epidemic and may contribute to increased HIV transmission. We evaluated the effect of suppressive acyclovir therapy on cervicovaginal HIV-1 shedding. METHODS: HIV-1- and herpes simplex virus type 2-coinfected women aged 18-49 years with CD4 counts >200 cells/microL were enrolled in a randomized crossover trial of suppressive acyclovir therapy (NCT00362596, http://www.clinicaltrials.gov). For each woman, monthly plasma and weekly cervicovaginal lavage specimens were collected; the mean of the monthly median cervicovaginal lavage HIV-1 viral load and plasma HIV-1 viral load was compared. RESULTS: Sixty-seven women were enrolled; at baseline, median CD4 count was 366 cells/microL, and median HIV-1 plasma viral load was 4.6 log10 copies/mL. The mean cervicovaginal lavage HIV-1 viral load was 1.9 (SD 0.8) log10 copies/mL during the acyclovir month and 2.2 (SD 0.7) log10 copies/mL during the placebo month (P < 0.0001); the mean decrease in HIV was 0.3 log10 copies/mL. The mean plasma HIV viral load during the acyclovir month (3.78 log10 copies/mL) was reduced compared with the placebo month (4.26 log10 copies/mL, P < 0.001). CONCLUSIONS: Acyclovir reduced HIV genital shedding and plasma viral load among HIV-1- and herpes simplex virus type 2-coinfected women. Further data from clinical trials will examine the effect of suppressive therapy on HIV transmission.

Maternal herpes simplex virus type 2 coinfection increases the risk of perinatal HIV transmission: possibility to further decrease transmission?

OBJECTIVES: To evaluate the association between maternal herpes simplex virus type 2 seropositivity and genital herpes simplex virus type 2 shedding with perinatal HIV transmission. STUDY DESIGN: Evaluation of women who participated in a 1996-1997 perinatal HIV transmission prevention trial in Thailand. METHODS: In this nonbreastfeeding population, women were randomized to zidovudine or placebo from 36 weeks gestation through delivery; maternal plasma and cervicovaginal HIV viral load and infant HIV status were determined for the original study. Stored maternal plasma and cervicovaginal samples were tested for herpes simplex virus type 2 antibodies by enzyme-linked immunoassay and for herpes simplex virus type 2 DNA by real-time PCR, respectively. RESULTS: Among 307 HIV-positive women with available samples, 228 (74.3%) were herpes simplex virus type 2 seropositive and 24 (7.8%) were shedding herpes simplex virus type 2. Herpes simplex virus type 2 seropositivity was associated with overall perinatal HIV transmission [adjusted odds ratio, 2.6; 95% confidence interval, 1.0-6.7)], and herpes simplex virus type 2 shedding was associated with intrapartum transmission (adjusted odds ratio, 2.9; 95% confidence interval, 1.0-8.5) independent of plasma and cervicovaginal HIV viral load, and zidovudine treatment. Median plasma HIV viral load was higher among herpes simplex virus type 2 shedders (4.2 vs. 4.1 log(10)copies/ml; P = 0.05), and more shedders had quantifiable levels of HIV in cervicovaginal samples, compared with women not shedding herpes simplex virus type 2 (62.5 vs. 34.3%; P = 0.005). CONCLUSION: We found an increased risk of perinatal HIV transmission among herpes simplex virus type 2 seropositive women and an increased risk of intrapartum HIV transmission among women shedding herpes simplex virus type 2. These novel findings suggest that interventions to control herpes simplex virus type 2 infection could further reduce perinatal HIV transmission.