Prevalence of cryptococcal antigenemia and cost-effectiveness of a cryptococcal antigen screening program--Vietnam.

Background: An estimated 120,000 HIV-associated cryptococcal meningitis (CM) cases occur each year in South and Southeast Asia; early treatment may improve outcomes. The World Health Organization (WHO) recently recommended screening HIV-infected adults with CD4<100 cells/mm(3) for serum cryptococcal antigen (CrAg), a marker of early cryptococcal infection, in areas of high CrAg prevalence. We evaluated CrAg prevalence and cost-effectiveness of this screening strategy in HIV-infected adults in northern and southern Vietnam.

Natural polymorphisms of HIV-1 CRF01_AE integrase coding region in ARV-naïve individuals in Cambodia, Thailand and Vietnam: an ANRS AC12 working group study.

The HIV integrase enzyme is essential for the HIV life cycle as it mediates integration of HIV-1 proviral DNA into the infected cell's genome. Recently, the development of drugs capable of inhibiting integrase has provided major new options for HIV-infected, treatment-experienced patients with multidrug resistant virus, as well treatment-naïve patients. More than 40 amino acid substitutions within integrase have been described as associated mostly with resistance of HIV B-subtypes to currently available integrase inhibitors (INIs).

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.

In-house HIV-1 RNA real-time RT-PCR assays: principle, available tests and usefulness in developing countries.

The principle of currently available licensed HIV-1 RNA assays is based on real-time technologies that continuously monitor the fluorescence emitted by the amplification products. Besides these assays, in-house quantitative (q) real-time reverse transcription (RT)-PCR (RT-qPCR) tests have been developed and evaluated particularly in developing countries, for two main reasons. First, affordable and generalized access to HIV-1 RNA viral load is urgently needed in the context of expected universal access to prevention and antiretroviral treatment programs in these settings.

Complete genome analysis of hepatitis C virus subtypes 6t and 6u.

Hepatitis C virus (HCV) genomes exhibit high nucleotide sequence diversity. In this study, we performed complete genome sequence analysis of 11 HCV genotype 6 samples from Vietnam and Thailand. We identified nine HCV complete genomes belonging to subtypes 6a (D9), 6e (D42 and D88), 6f (TH52), 6i (TH24), 6l (D33), 6n (TH22 and TH31) and 6o (D85).

Characterization of hepatitis C virus deletion mutants circulating in chronically infected patients.

Hepatitis C virus (HCV) has a linear positive-stranded RNA genome of approximately 9,600 nucleotides in length and displays a high level of sequence diversity caused by high mutation rates and recombination. However, when we performed long distance reverse transcription-PCRs on HCV RNA isolated from serum of chronic HCV patients, not only full-length HCV genomes but also HCV RNAs which varied in size from 7,600 to 8,346 nucleotides and contained large in-frame deletions between E1 and NS2 were amplified. Carefully designed control experiments indicated that these deletion mutants are a bona fide natural RNA species, most likely packaged in virions.

Genotyping hepatitis C viruses from Southeast Asia by a novel line probe assay that simultaneously detects core and 5' untranslated regions.

Hepatitis C viruses (HCVs) display a high level of sequence diversity and are currently divided into six genotypes. A line probe assay (LiPA), which targets the 5' untranslated region (5'UTR) of the HCV genome, is widely used for genotyping. However, this assay cannot distinguish many genotype 6 subtypes from genotype 1 due to high sequence similarity in the 5'UTR.

Identification of a naturally occurring recombinant genotype 2/6 hepatitis C virus.

Hepatitis C viruses (HCVs) display a high level of sequence diversity and are currently classified into six genotypes and an increasing number of subtypes. Most likely, this heterogeneity is caused by genetic drift; evidence for recombination is scarce. To study the molecular heterogeneity of HCV in Vietnam, we analyzed 58 HCV RNA-positive sera from Vietnamese blood donors by sequence analysis of the CORE and NS5B regions.

Assessing the performance of overseas tuberculosis screening programs: a study among US-bound immigrants in Vietnam.

Background: Tuberculosis cases in foreign-born persons account for more than 50% of all tuberculosis cases in the United States. The Institute of Medicine has recommended enhancing overseas screening as one measure to support tuberculosis elimination efforts. We assessed the ability of overseas tuberculosis screening (chest radiograph followed by 3 acid-fast bacilli sputum smears for persons with abnormal chest radiographs [suggestive of active tuberculosis]) to detect pulmonary tuberculosis disease among US-bound immigrants with abnormal chest radiographs.

Prevalence of hepatitis virus types B through E and genotypic distribution of HBV and HCV in Ho Chi Minh City, Vietnam.

A molecular epidemiological survey of various hepatitis viral infections, including hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV), was carried out in Ho Chi Minh City, Vietnam. This study included of 295 patients with liver disease (234 viral related and 61 non-viral related) and 100 healthy individuals. The infection rates of HBV and HCV in 234 liver disease patients with acute hepatitis, chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, were 31.