38 research outputs found

    Molecular Epidemiology of Human Enterovirus 71 Strains and Recent Outbreaks in the Asia-Pacific Region: Comparative Analysis of the VP1 and VP4 Genes

    Get PDF
    This study provides a comprehensive overview of the molecular epidemiology of human enterovirus 71 (HEV71) in the Asia-Pacific region from 1997 through 2002. Phylogenetic analysis of the VP4 and VP1 genes of recent HEV71 strains indicates that several genogroups of the virus have been circulating in the Asia-Pacific region since 1997. The first of these recent outbreaks, described in Sarawak (Malaysian Borneo) in 1997, was caused by genogroup B3. This outbreak was followed by large outbreaks in Taiwan in 1998, caused by genogroup C2, and in Perth (Western Australia) in 1999, where viruses belonging to genogroups B3 and C2 cocirculated. Singapore, Taiwan, and Sarawak had HEV71 epidemics in 2000, caused predominantly by viruses belonging to genogroup B4; however, large numbers of fatalities were observed only in Taiwan. HEV71 was identified during an epidemic of hand, foot and mouth disease in Korea; that epidemic was found to be due to viruses constituting a new genogroup, C3

    Epidemic Hand, Foot and Mouth Disease Caused by Human Enterovirus 71, Singapore

    Get PDF
    Singapore experienced a large epidemic of hand, foot and mouth disease (HFMD) in 2000. After reviewing HFMD notifications from doctors and child-care centers, we found that the incidence of HFMD rose in September and declined at the end of October. During this period, 3,790 cases were reported. We performed enteroviral cultures on 311 and 157 specimens from 175 HFMD patients and 107 non-HFMD patients, respectively; human enterovirus 71 (HEV71) was the most frequently isolated virus from both groups. Most of the HFMD patients were <4 years of age. Three HFMD and two non-HFMD patients died. Specimens from two HFMD and both non-HFMD patients were culture positive for HEV71; a third patient was possibly associated with the virus. Autopsies performed on all three HFMD and one of the non-HFMD case-patients showed encephalitis, interstitial pneumonitis, and myocarditis. A preparedness plan for severe HFMD outbreaks provided for the prompt, coordinated actions needed to control the epidemic

    Atypical SARS and Escherichia coli Bacteremia

    Get PDF
    We describe a patient with severe acute respiratory syndrome (SARS) whose clinical symptoms were masked by Escherichia coli bacteremia. SARS developed in a cluster of healthcare workers who had contact with this patient. SARS was diagnosed when a chest infiltrate developed and when the patient’s brother was hospitalized with acute respiratory failure. We highlight problems in atypical cases and offer infection control suggestions

    Emergence of Oseltamivir-Resistant Pandemic (H1N1) 2009 Virus within 48 Hours

    Get PDF
    An oseltamivir-resistant influenza A pandemic (H1N1) 2009 virus evolved and emerged from zero to 52% of detectable virus within 48 hours of a patient’s exposure to oseltamivir. Phylogenetic analysis and data gathered by pyrosequencing and cloning directly on clinical samples suggest that the mutant emerged de novo

    First-principles computational study of hydrogen storage in silicon clathrates

    No full text
    <p>Density functional theory (DFT) was utilized to compute the gravimetric capacity, volumetric capacity, and the binding energy of hydrogen molecules in silicon clathrates with guest (A) atoms such as Ba, Na, and Li, and framework substitutional atoms (M) such as C, Al, and Cu. The DFT computations show that these Type I intermetallic clathrates can accommodate a large number of hydrogen molecules, equivalent to 10 wt.%, and such hydrogenated structures, A<i><sub>x</sub></i>(H<sub>2</sub>)<i><sub>n</sub></i>M<i><sub>y</sub></i>Si<sub>46−<i>y</i></sub>, occur with only a modest increase in lattice volume and a binding energy within the desirable range of 0.1–0.6 eV/H<sub>2</sub> for hydrogen storage at or near ambient temperature.</p> <p><b>IMPACT STATEMENT</b></p> <p>This paper identifies a number of Type I silicon clathrates that can accommodate large amounts of hydrogen molecules (10 wt.%) and may be suitable as hydrogen storage materials.</p
    corecore