[Evaluation of a new vesion of the human immunodeficiency virus antigen and antibody combination assay with improved sensitivity in HIV-1 p24 antigen detection].

The performance of a new version of the HIV p24 antigen and antibody combination assays (Genscreen Ultra HIV Ag-Ab) was evaluated by comparing it with three other fourth-generation enzyme immunoassays (Architect HIV Ag/Ab Combo assay, VIDAS HIV DUO Quick and Genscreen Plus HIV Ag-Ab). The assays were examined with 200 HIV positive samples, 1,000 HIV negative samples, 30 samples (28 positives including 24 samples of subtype A, B, B', C, D, F, G, B/D, CRF01_AE in HIV-1 group M, one sample of HIV-1 group O, three samples of HIV-2 and two negatives) of one worldwide HIV performance panel, 59 samples of ten HIV-1 seroconversion panels and the WHO international standard HIV-1 p24 antigen. Both the sensitivity and specificity of Genscreen Ultra HIV Ag-Ab were 100%.

[Prevalence of HIV and sexually transmitted infections and characteristics of men who have sex with men at a community-based center in Yokohama, Japan].

Objectives: To investigate the characteristics of men who have sex with men (MSM) in a sample of men who sought voluntary testing and counseling (VCT) for human immunodeficiency virus (HIV) and sexually transmitted infections (STIs) in a community-based center in Yokohama, Japan. The prevalence of HIV/STIs and the incidence rate of HIV were also assessed.

Methods: We investigated VCT records of 449 clients who received free anonymous night VCT services between 2008 and 2011.

Emergence in Japan of an HIV-1 variant associated with transmission among men who have sex with men (MSM) in China: first indication of the International Dissemination of the Chinese MSM lineage.

A survey of HIV-1 strains circulating in the Tokyo-Kanagawa metropolitan area of Japan during 2004 to 2011 (n = 477) identified six Japanese males (patients 1 to 6), who harbored viruses with genome segments derived from a distinct CRF01_AE variant uniquely found among men who have sex with men (MSM) in China (designated CN.MSM.01-1).

[Recent progress in HIV screening tests and nucleic acid tests].

HIV testing plays a crucial role in detecting and monitoring HIV infection. Diagnosis of HIV infection is basically made by sequential two tests: a screening test with an enzyme immunoassay(EIA) and a confirmatory test with Western blot. The most recent EIAs, used in commercial laboratories, identify HIV infection earlier because they detect both HIV-1 antibody and antigen.

A human immunodeficiency virus screening algorithm to address the high rate of false-positive results in pregnant women in Japan.

Background: Prenatal human immunodeficiency virus (HIV) testing is essential for the prevention of mother-to-child transmission. However, false-positive results of screening testing are a concern as they may cause unnecessary emotional stress to pregnant women waiting for confirmatory test results. In regions with an extremely low prevalence, the positive predictive values of screening are unacceptably low rate.

[Testing services for sexually transmitted infections in Japan, public funding for HIV testing compared to public funding for other STI testing].

HIV and other STIs testing services of public funded setting have not been integrated in Japan. Public health centers and other public funded testing sites provide free anonymous HIV test. This has been playing an important role to confirm almost half of asymptomatic patients.

Quantitation of HIV-1 group M proviral DNA using TaqMan MGB real-time PCR.

The level of human immunodeficiency virus type 1 (HIV-1) proviral DNA is likely to be an important marker of the long-term effectiveness of highly active antiretroviral therapy. A new method was developed for quantifying HIV-1 group M proviral DNA using TaqMan real-time PCR, in which degenerate primers and an MGB probe were used to resolve the difference in amplification efficiencies among different subtypes. The present assay provided good linearity and accuracy in the range of 4-5000 copies of proviral DNA in 0.

[Evaluation of new fourth-generation human immunodeficiency virus antigen and antibody detection assay with enzyme-linked fluorescent immunoassay].

We evaluated the fourth-generation HIV screening assay VIDAS HIV DUOII (DUOII) based on ELFA for simultaneous detection of anti-HIV-1 and anti-HIV-2 antibodies and HIV-1 p24 antigen through comparison with other HIV antigen-antibody detection assays. Materials were 1228 HIV-negative specimens, 95 HIV-antibody-positive specimens, and HIV commercial panels. The specificity of DUOII was 99.

[Evaluation of a new real-time PCR assay kit for quantification of human immunodeficiency virus RNA in plasma].

We evaluated the use of COBAS TaqMan HIV-1 for highly pure system (COBAS TaqMan) recently developed as a second-generation quantification of human immunodeficiency virus type 1 (HIV-1) RNA. The linearity, sensitivity, reproducibility, and effects of possibly interfering materials were examined and results compared to those of AMPLICOR HIV-1 MONITOR Test version 1.5 (AMPLICOR) using 6 virus isolates that were all different subtypes.

Drug-resistant HIV-1 prevalence in patients newly diagnosed with HIV/AIDS in Japan.

The increasing prevalence of drug-resistant HIV transmission has become a critical epidemic in the world today. Studies in developed countries reported 8-27% of newly diagnosed HIV/AIDS patients are infected by drug-resistant strains. To determine the prevalence of drug-resistant HIV-1 among newly diagnosed cases in Japan, eight HIV/AIDS clinical centers, three public health laboratories and the National Institute of Infectious Diseases conducted a nationwide survey.

[Introduction of rapid HIV tests to a public health center in Japan and evaluation of its effects].

Objective: As an attempt to make HIV testing more accessible to many people, rapid HIV tests were introduced to a public health center. We evaluated logistic issues and effects of the introduction.

Methods: In January 2003, the Tochigi Prefectural Kennan Public Health and Welfare Center introduced rapid HIV tests simultaneously with conventional HIV tests.

Current state and need for improvement of system for antibody testing and counseling for HIV infection at public health centers in Japan.

Background: Public Health Centers (PHCs) throughout Japan have been playing a role in preventing HIV in Japan. The number of HIV seropositive persons and AIDS patients is increasing from year to year in Japan.

Methods: A survey regarding the HIV antibody test was sent out to 594 PHCs between January 1997 and December 2001.

Analysis of a long-term discrepancy in drug-targeted genes in plasma HIV-1 RNA and PBMC HIV-1 DNA in the same patient.

Drug-resistance genotypes were investigated in a patient under treatment with anti-HIV drugs. Since the drug resistance-associated mutations in plasma HIV-1 RNA and proviral DNA in peripheral blood mononuclear cells (PBMCs) were inconsistent, changes were followed over time, and the discrepancy was shown to persist for a long period. In plasma HIV-1 RNA, D67N, K70R, T215Y, and Y188L were present in the reverse transcriptase (RT) region, and two primary mutations, I84V and L90M, were noted in the protease (Pro) region.

Identification of attenuated variants of HIV-1 circulating recombinant form 01_AE that are associated with slow disease progression due to gross genetic alterations in the nef/long terminal repeat sequences.

We identified an unusual case of human immunodeficiency virus type 1 (HIV-1) infection in a patient (GM43) who exhibited a persistently low antibody response and undetectable viral load during a 5-year follow-up period. GM43 harbored HIV-1 circulating recombinant form 01_AE with gross deletions in the nef/long terminal repeat (LTR) region. The sizes of the deletions increased progressively from 84 to >400 bp during the 5-year period.

A case of symptomatic primary HIV infection.

A 30-year-old homosexual Japanese man had fourteen days of fever, malaise, appetite loss, sore throat, and four days of diarrhea and slightly congested eyes before he developed a skin eruption. He presented with measles-like exanthems on his face, trunk, and extremities. Deep red enanthems were seen on his left buccal mucosa opposite the premolar teeth, and whitish enanthems were seen on the buccal and gingival mucosa.

[Evaluation of flow-through immunoassay for rapid detection of influenza A and B viruses].

We evaluated a flow-through immunoassay for rapid detection of influenza A and B viral antigens, RapidTesta FLU AB (Daiichi Pure Chemicals Co., Ltd., Tokyo, Japan), by using 507 specimens collected from patients with influenza-like symptoms during the 2002/2003 influenza season in Japan.

[Evaluation of an immunochromatography test using enzyme immunoassay for rapid detection of influenza A and B viruses].

We evaluated the performance of an improved version of Espline Influenza A & B-N (Fujirebio Inc., Japan), an immunochromatography test using enzyme immunoassay for rapid diagnosis of influenza A and B. The test produced positive results for four strains of influenza viruses and thirty-one influenza viral antigens and negative results for all of thirty strains of other respiratory viruses that were tested.

Transfusion-transmitted hepatitis E caused by apparently indigenous hepatitis E virus strain in Hokkaido, Japan.

Background: In industrialized countries, sporadic cases of hepatitis E have been reported in individuals who have never been in an endemic area. Hepatitis E virus (HEV) infection commonly occurs via the fecal-oral route but a potential risk of transfusion transmission route has been suggested.

Study Design And Methods: A 67-year-old Japanese male patient who had never been abroad received a transfusion of blood from 23 voluntary donors and developed acute hepatitis with unknown etiology after transfusion.

Human immunodeficiency virus in Uzbekistan: epidemiological and genetic analyses.

This study investigates the molecular epidemiology of HIV in Uzbekistan--a former Soviet Union (FSU) country located in central Asia. A total of 18,910,370 subjects were involved in an HIV serological examination through a population survey conducted in 1987-2002. Rapid changes in epidemiological dynamics and transmission modes have been observed since 1999: incidence rose from 25 newly HIV-infected subjects per year to more than 100 new cases per month within the first half of 2002, and the rate of intravenous drug use (IVDU)-associated HIV infection increased to 75% per year during the same period.