Surveillance of transmitted HIV drug resistance using matched plasma and dried blood spot specimens from voluntary counseling and testing sites in Ho Chi Minh City, Vietnam, 2007-2008.

During 2007-2008, surveillance of transmitted human immunodeficiency virus (HIV) drug resistance (TDR) was performed following World Health Organization guidance among clients with newly diagnosed HIV infection attending voluntary counseling and testing (VCT) sites in Ho Chi Minh City (HCMC), Vietnam. Moderate (5%-15%) TDR to nonnucleoside reverse-transcriptase inhibitors (NNRTIs) was observed among VCT clients aged 18-21 years. Follow-up surveillance of TDR in HCMC and other geographic regions of Vietnam is warranted. Data generated will guide the national HIV drug resistance surveillance strategy and support selection of current and future first-line antiretroviral therapy and HIV prevention programs.

A novel flat-panel photobioreactor for simultaneous production of lutein and carbon sequestration by Chlorella sorokiniana TH01.

Carbon dioxide is the major cause of global warming. However, it is a carbon source for phototrophic production of chemicals from microalgae. In this work, a novel flat-panel photobioreactor (FPP) was used for maximization of biomass and lutein production and CO2 fixation by a lutein-rich C. sorokiniana TH01. CO2 concentration, light intensity and aeration rate were optimized as 5%, 150 µmol/m2/s and 1 L/min, respectively. The highest biomass productivity, lutein productivity and CO2 fixation efficiency were measured for indoor single and sequential FPPs were 284 - 469 mg/L/d, 2.57 - 4.57 mg/L/d, and 63 - 100%, respectively. In a climatic condition of 25.5 - 33 °C and 86 - 600 µmol/m2/s, C. sorokiniana TH01 achieved lutein productivity and CO2 fixation efficiency of 2.1 - 3.03 mg/L/d and 56 - 81%, respectively, while the comparable biomass productivity of 284 - 419 mg/L/d was maintained. This pioneered FPP system was efficiently demonstrated for production of algal lutein from CO2.

Failure of human immunodeficiency virus enzyme immunoassay to rule out infection among polymerase chain reaction-negative Vietnamese infants at 12 months of age.

BACKGROUND: : Previous studies have demonstrated that >90% of HIV-uninfected infants serorevert, as seen in the results of enzyme immunoassay (EIA) testing by 12 months of age, making it feasible to confirm or rule out infection. We assessed the reliability of EIA in a cohort of Vietnamese infants. METHODS: : HIV-exposed, uninfected infants enrolled in a parent diagnostic and monitoring study from February 2005 through August 2006 were eligible for inclusion in a prospective cohort study of HIV-EIA performance. Testing using 2 standard assays (Genscreen HIV 1/2 version 2, Bio-Rad; Murex 1.2.0, Murex Biotech) was initiated at 12 months of age. Infants were categorized as EIA-negative (seroreverted; negative Genscreen), EIA-indeterminate (positive Genscreen, negative Murex), or EIA-positive (Genscreen and Murex positive). RESULTS: : Of 273 infants included in the study, 59 (22%) were EIA-negative at 12 months, 131 (48%) were indeterminate, and 83 (30%) were EIA-positive; specificity 21.6 (95% confidence interval: 16.6, 26.3). Infants with positive EIAs at 12 months were 74% more likely than EIA-indeterminate infants to test indeterminate or positive at 18 months (risk ratio, 1.74, 95% confidence interval: 1.15, 2.64; P = 0.03). CONCLUSIONS: : Expectations regarding infant seroreversion by standard EIAs should be reassessed to reflect potential cross-regional differences in their performance.

Community, family, and partner-related stigma experienced by pregnant and postpartum women with HIV in Ho Chi Minh City, Vietnam.

Pregnant and postpartum women with HIV often face stigma and discrimination at home and in the community. In Vietnam, associations between HIV and the "social evils" of drug use and sex work contribute to stigmatization of people with HIV. We conducted a qualitative study to explore discrimination experienced by HIV-positive pregnant and postpartum women in Ho Chi Minh City at home and in the community. We conducted 20 in-depth interviews and two focus group discussions. Participants described managing disclosure of their HIV infection because of fear of stigma and discrimination, particularly to the wider community. In cases where their HIV status was disclosed, women experienced both discrimination and support. The findings highlight the need for targeted interventions to support pregnant and postpartum women with HIV, particularly during this period when they are connected to the healthcare system and more readily available for counseling.

On bounds in Poisson approximation for distributions of independent negative-binomial distributed random variables.

Using the Stein-Chen method some upper bounds in Poisson approximation for distributions of row-wise triangular arrays of independent negative-binomial distributed random variables are established in this note.

Factors associated with HIV viral load suppression on antiretroviral therapy in Vietnam.

BACKGROUND: Limited data are available on HIV viral suppression rates among men and women on antiretroviral therapy (ART) and factors associated with HIV RNA viral load (VL) suppression in Vietnam. METHODS: We conducted a cross-sectional survey of 1255 adult patients on ART for at least 1 year across four provinces in Vietnam. Data collection included a standardised questionnaire, routine laboratory testing, and an HIV VL assay. Bivariate and logistic multivariate analyses were conducted to assess viral suppression rates and factors associated with unsuppressed HIV VL. RESULTS: The median age was 34.5 years and the median time on ART was 46 months. Gender was 66% male (n=828) and 34% female (n=427). HIV viral suppression below 1000 copies/mL was 93%. Viral suppression among woman was not significantly different than among men (93.7% vs 92.9%; P=0.59). On multivariate analysis, unsuppressed HIV VL was independently associated with lower CD4 cell count, social isolation, high stigma, not receiving a single-tablet daily regimen, multiple late appointments in past year, and immunological failure. CONCLUSION: On-treatment viral load suppression rates in Vietnam are high and already exceed the UNAIDS 90% target for viral suppression on ART. Gender does not impact viral suppression rates of patients on ART in Vietnam. Access to routine viral load testing should be improved, adherence monitoring and counselling streamlined, and ART regimens simplified to maintain viral suppression rates, as more people start ART. Psychological and social factors are also associated with unsuppressed HIV VL, necessitating treatment support interventions to address social isolation and stigma among people living with HIV in Vietnam.

Correlation of prospective and cross-sectional measures of HIV type 1 incidence in a higher-risk cohort in Ho Chi Minh City, Vietnam.

The primary aim of this study was to estimate HIV incidence within a high-risk population in Ho Chi Minh City (HCMC), Vietnam using both cross-sectional and prospective methodologies. A secondary aim was to develop a local correction factor for the BED and avidity index incidence assays. The research study design consisted of three phases: (1) cross-sectional, (2) prospective, and (3) BED false recent (BED FR). A total of 1619 high-risk, sexually active individuals were enrolled in the cross-sectional phase and 355 of the opiate-negative, HIV-negative women were subsequently enrolled in the prospective phase. Four-hundred and three men and women with known HIV infection duration of greater than 12 months were enrolled in the BED FR phase. The HIV prevalence for all participants in the cross-sectional phase was 15.8%. HIV incidence in the cross-sectional group was estimated using the BED IgG capture assay and AxSYM avidity index assay for recent HIV infection and incidence within the prospective cohort was determined by observations of HIV seroconversion. HIV incidence in opiate-negative women was estimated using the BED assay to be 0.8% unadjusted and 0.5% after applying the locally derived BED false recent rate of 1.7%; no seroconversions were observed in the prospective cohort. We also screened the cross-sectional samples for evidence of acute infection using nucleic acid testing, 4th generation HIV EIA, and SMARTube coupled with Genscreen and Determine diagnostic tests; no confirmed acute infections were identified by any method. HIV incidence within this opiate-negative study population was low and incidence estimates from the two methods compared favorably with each other. Incidence estimates and false recent rates using the AxSYM assay were higher: AI FRR of 2.7% and adjusted incidence of 1.7% per year (95% CI, 0.6, 2.8). By comparison, both HIV prevalence and incidence estimates for the opiate-positive group were higher.

HIV-related risk behaviors among female sex workers in Ho Chi Minh City, Vietnam.

This study quantitatively and qualitatively described HIV risk behaviors among Vietnamese female sex workers (FSWs) who work at three distinct venues in Ho Chi Minh City: street, massage parlors, and bars/clubs. Although 35% of the participants had never been tested for HIV, 18% of street and 7% of bar/club FSWs reported being positive. Almost all massage parlor FSWs had never used a condom for oral sex. Inconsistent condom use for vaginal sex with customers was more prevalent among bar/club FSWs (85%) than massage parlor (72%) and street FSWs (68%). Many participants reported difficulties in negotiating condom use with customers because of economic pressure, maintaining relationships, and lack of bargaining power. Bar/club FSWs revealed a difficult situation where drinking is part of their work. Thirty percent of street FSWs had injected drugs and reported addiction to heroin in relation to their helpless condition as FSWs. Street FSWs had the lowest levels of self-esteem and norms toward practicing safe sex and the highest levels of economic pressure. This study recommends future HIV prevention programs for FSWs in Vietnam that target their specific risk behaviors and work environments.

A qualitative study of stigma and discrimination against people living with HIV in Ho Chi Minh City, Vietnam.

Stigma and discrimination against people living with HIV/AIDS (PLHIV) are a pressing problem in Vietnam, in particular because of propaganda associating HIV with the "social evils" of sex work and drug use. There is little understanding of the causes and sequelae of stigma and discrimination against PLHIV in Vietnam. Fifty-three PLHIV participated in focus group discussions in Ho Chi Minh City. Nearly all participants experienced some form of stigma and discrimination. Causes included exaggerated fears of HIV infection, misperceptions about HIV transmission, and negative representations of PLHIV in the media. Participants faced problems getting a job, perceived unfair treatment in the workplace and experienced discrimination in the healthcare setting. Both discrimination and support were reported in the family environment. There is a need to enforce laws against discrimination and provide education to decrease stigma against PLHIV in Vietnam. Recent public campaigns encouraging compassion toward PLHIV and less discrimination from healthcare providers who work with PLHIV have been encouraging.

Changes in high-risk behaviors over time among young drug users in South Vietnam: a three-province study.

Vietnam is in the midst of an expanding HIV epidemic, primarily driven by an increase in injection drug use in young people. This study was conducted to understand the patterns and initiation of drug use, and the sexual risk behavior among youth in three provinces in southern Vietnam. A cross-sectional survey was conducted among male and female drug users under age 25 recruited from drug treatment centers (N = 560) and the community (N = 240) in Ho Chi Minh City, Dong Nai and Ba Ria-Vung Tau. The majority of those surveyed (82%) began by smoking heroin; after a year, 57% were injecting heroin and/or opium. Initiation of drug use frequently occurred in entertainment venues. Among injectors, 23% shared needles; 71% of all users were sexually active of whom 77% had unprotected sex. More than half of those recruited from treatment centers had previously been in drug treatment. Public health programs to prevent and treat the dual epidemics of HIV and drug abuse must be able to access and respond to the needs of youth, many of whom are unemployed and exposed to drug traffic.