Several human adenoviruses (HAdVs) can cause respiratory infections, some severe. HAdV-B7, which can cause severe respiratory disease, has not been recently reported in the United States but is ...reemerging in Asia. During October 2013-July 2014, Oregon health authorities identified 198 persons with respiratory symptoms and an HAdV-positive respiratory tract specimen. Among 136 (69%) hospitalized persons, 31% were admitted to the intensive care unit and 18% required mechanical ventilation; 5 patients died. Molecular typing of 109 specimens showed that most (59%) were HAdV-B7, followed by HAdVs-C1, -C2, -C5 (26%); HAdVs-B3, -B21 (15%); and HAdV-E4 (1%). Molecular analysis of 7 HAdV-B7 isolates identified the virus as genome type d, a strain previously identified only among strains circulating in Asia. Patients with HAdV-B7 were significantly more likely than those without HAdV-B7 to be adults and to have longer hospital stays. HAdV-B7 might be reemerging in the United States, and clinicians should consider HAdV in persons with severe respiratory infection.
Noroviruses (NoVs) are recognized as the leading cause of epidemic and sporadic acute gastroenteritis. Early detection of NoV is crucial to control the spread of the disease. In this study, we ...evaluated the diagnostic accuracy, analytical sensitivity, and analytical reactivity of the IDEIA Norovirus assay (an enzyme immunoassay EIA) in a prospective and retrospective study design. A total of 557 prospectively collected fecal samples and a panel of 97 archived fecal samples, including 21 different GI and GII genotypes, were tested by conventional reverse transcription-PCR (RT-PCR)/bidirectional sequencing, real-time RT-PCR, and electron microscopy. The sensitivity and specificity of the EIA were 57.6% and 91.9%, respectively. The sensitivity for detecting NoV in fecal samples from outbreaks improved from 44.1% when three samples were tested to 76.9% when five samples per outbreak were tested. The EIA was able to detect strains from 7 GI and 11 GII genotypes. The analytical sensitivity of the EIA was 3.1 x 10⁶ and 1.6 x 10⁷ virus particles g⁻¹ of fecal sample for NoV GI and GII strains, respectively. Most GII samples positive by EIA had a threshold cycle (CT) of <26.5, and 50% of the GII samples negative by EIA had a CT of >25.6, suggesting that, although strains from genotypes GI.8, GII.10, and GII.16 were not detected, the low sensitivity of the EIA is primarily caused by low virus concentration. In conclusion, the current EIA may be of use as a rapid screening test during a norovirus outbreak investigation when multiple fecal samples are available; however, sporadic samples should be tested by molecular methods.
We evaluated data from gastroenteritis outbreaks in Oregon to assess sensitivity of stool testing for norovirus and determine number of specimens needed to confirm norovirus as the cause. Norovirus ...can be readily confirmed if 3-6 specimens are collected any time ≤7 days after onset of diarrhea and for almost that long after symptoms resolve.
Background. The Influenza Incidence Surveillance Project (IISP) monitored outpatient acute respiratory infection (ARI; denned as the presence of ≥2 respiratory symptoms not meeting ILI criteria) and ...influenza-like illness (ILI) to determine the incidence and contribution of associated viral etiologies. Methods. From August 2010 through July 2011, 57 outpatient healthcare providers in 12 US sites reported weekly the number of visits for ILI and ARI and collected respiratory specimens on a subset for viral testing. The incidence was estimated using the number of patients in the practice as the denominator, and the virus-specific incidence of clinic visits was extrapolated from the proportion of patients testing positive. Results. The age-adjusted cumulative incidence of outpatient visits for ARI and ILI combined was 95/1000 persons, with a viral etiology identified in 58% of specimens. Most frequently detected were rhinoviruses/enteroviruses (RV/EV) (21%) and influenza viruses (21%); the resulting extrapolated incidence of outpatient visits was 20 and 19/1000 persons respectively. The incidence of influenza virus-associated clinic visits was highest among patients aged 2-17 years, whereas other viruses had varied patterns among age groups. Conclusions. The IISP provides a unique opportunity to estimate the outpatient respiratory illness burden by etiology. Influenza virus infection and RV/EV infection(s) represent a substantial burden of respiratory disease in the US outpatient setting, particularly among children.
We evaluated data from gastroenteritis outbreaks in Oregon to assess sensitivity of stool testing for norovirus and determine number of specimens needed to confirm norovirus as the cause. Norovirus ...can be readily confirmed if 3–6 specimens are collected any time
<
7 days after onset of diarrhea and for almost that long after symptoms resolve.
Polyoma virions have different attachment proteins which are responsible for hemagglutination of erythrocytes and attachment to cultured mouse kidney cells (MKC). Virion binding studies demonstrated ...that MKC possess specific (productive infection) and nonspecific (nonproductive) receptors. Empty polyoma capsids have hemagglutination activity and bind to non-specific MKC receptors, but they are not capable of competing for specific virion cell receptors or preventing productive infection. Isoelectric focusing of the virion major capsid protein, VP1, separated this protein into six species (A through F). These species had identical amino acid sequences, but differed in degree of modification (phosphorylation, acetylation, sulfation and hydroxylation). Evidence based upon precipitation with specific antisera supports the view that VP1 species E is required for specific adsorption and that D and F are required for hemagglutination. The virion attachment domain has been localized to an 18 kilodalton fragment of the C-terminal region of VP1. Monopinocytotic vesicles containing 125I-labeled polyoma virions were isolated from infected MKC. A crosslinker was used to bind the MKC cell receptor(s) covalently to VP1 attachment protein, and a new 120 kilodalton band was identified by SDS-PAGE. An anti-idiotype antibody prepared against a neutralizing polyoma monoclonal antibody was used to identify a putative 50 kilodalton receptor protein from a detergent extract of MKC, as well as from an MKC membrane preparation.
PDF
