Intervirology
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Rates of infection and phylogenetic analysis of GB virus-C among Kuwaiti and Jordanian blood donors.
GB virus-C/hepatitis G virus (GBV-C/HGV), collectively known as GBV-C, has been reported to be associated with non-A-E hepatitis. The aim of this study was to determine the rate of infection and genotypic characteristics of GBV-C among Kuwaiti and Jordanian blood donors. ⋯ GBV-C/HGV was detectable at rates relatively comparable with other regions in the world in Kuwaiti and Jordanian blood donors, although the significance of which remains controversial. More interesting is the dominance of GBV-C genotype 2 among the two populations, which remains to be explained.
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Screening of blood before transfusion is an effective strategy to reduce transfusion-transmitted viruses. However, reports on viral marker trends among the donor population are scarce. This study looked at trends in the seroprevalence of hepatitis B (HBV) and C (HCV) and human immunodeficiency virus (HIV). ⋯ The seroprevalence rates for HIV and HBsAg fluctuated greatly during the study period while the seroprevalence of HCV was consistent. The screening kits used may be partly responsible for these fluctuations. Innovative programs for donor education, with the use of a formal questionnaire in donor selection, are recommended to ensure a safe donor population.
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The aim of this serological study was to demonstrate the extent to which antibodies react against subsequent drift variants, after vaccination with split vaccine (Fluarix). Antibody titers have been determined by hemagglutination inhibition test (HI) against different influenza A and B drift variants in sera from three past multicenter trials. Individuals of two different age groups, i.e. 18-60 years and above 60 years, were enrolled. ⋯ The genetically more variable component influenza A/H3N2 shows somewhat lower protection rates. High levels of cross immunogenicity were found between the variants of influenza A/Panama/2007/99 (H3N2) and influenza A/Wyoming/3/2003 (H3N2). The results demonstrate that in situations where drift variants emerge too late to be included in the influenza vaccine formulation, the cross-protection conferred must be evaluated on a case-by-case basis.
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Dengue virus is spread in tropical areas of the world and is the causative agent of dengue fever and dengue hemorrhagic fever. It is horizontally transmitted to humans by infected Aedes mosquitoes, but it is also able to be vertically or transovarially transmitted to insect progeny. ⋯ The results presented here strongly suggest that dengue virus can be vertically transmitted in mosquitoes from Oaxaca, but more studies will be necessary to analyze the epidemiological impact of this mechanism of transmission.
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Interferon (IFN)-alpha, -beta and -gamma have been shown to be only marginally effective against severe acute respiratory syndrome coronavirus (SARS-CoV) replication in Vero cell lines. We investigated the combination of type I IFNs (IFN-alpha or -beta) and IFN-gamma for antiviral activity and found that such combinations synergistically inhibited SARS-CoV replication in Vero cells, using yield reduction assay and the isobologram and combination index methods of Chou and Talalay for evaluation. The highly synergistic anti-SARS-CoV action of type I IFNs and IFN-gamma parallels the marked increase in 2'-5'-oligoadenylate synthetase and p56 mRNAs following exposure in Vero cells to either IFN-alpha or -beta and IFN-gamma compared with the transcriptional levels obtained after stimulation with either IFN alone. These results demonstrate that SARS-CoV, although only moderately sensitive to the antiviral action of the individual types of IFN, is highly sensitive to a combination of type I and II IFNs, which suggests that such combinations may have potential in the treatment of SARS-CoV infections.