37 research outputs found
Contributing Factors in a Successful Foodborne Outbreak Investigation: an Analysis of Data Collected by the Foodborne Diseases Active Surveillance Network (FoodNet), 2003-2010.
Background. Foodborne disease is estimated to cause 48 million illnesses annually in the US resulting in 3000 deaths [1]. Although most infections occur as sporadic cases, outbreak surveillance offers valuable insight about the foods and pathogens responsible for illnesses [2]. A total of 1632 foodborne disease outbreaks were reported during 2011-2012 [3] and recent data indicates an overall decrease in the number of outbreaks reported each year [4]. Understanding which factors contribute to the successful identification of a food vehicle in a foodborne outbreak investigation is crucial for improving outbreak response [5-10]. The purpose of this study was to describe outbreak characteristics and to determine which may be associated with the success of a foodborne outbreak investigation (i.e. one in which a food vehicle has been reported).
Methods. A foodborne disease outbreak was defined as the event in which two or more people acquired similar illnesses from consuming the same food or beverage. Outbreaks occurring in FoodNet sites during 2003 through 2010 were included in the analysis.
Results. Data were available for 1441 (87%) of the 1655 foodborne disease outbreaks documented in FoodNet Outbreak Supplement forms from 2003 through 2010. A food vehicle was identified in 692 of the 1441 (48%) outbreaks. Six outbreak characteristics remained statistically significant in both univariate and multivariate analyses: environmental and/or food culture collection, FDA or state agriculture involvement, outbreak size, case-control studies, and number of fecal specimens tested for norovirus.
Conclusions. Less than half of foodborne outbreaks examined here resulted in a food vehicle being identified. Having more robust resources available for outbreak detection and investigation may improve likelihood of a food vehicle being identified
Photocurrent dynamics in a poly(phenylene vinylene)-based photorefractive composite,” Phys
All parameters describing the charge carrier dynamics in a poly͑phenylene vinylene͒-based photorefractive ͑PR͒ composite relevant to PR grating dynamics were determined using photoconductivity studies under various illumination conditions. In particular, the values of the coefficients for trap filling and recombination of charges with ionized sensitizer molecules could be extracted independently. It is concluded that the PR growth time without preillumination is mostly determined by the competition between deep trap filling and recombination with ionized sensitizer molecules. Further, the pronounced increase in PR speed upon homogeneous preillumination ͑gating͒ as reported recently is quantitatively explained by deep trap filling
Central venous-to-arterial carbon dioxide difference as a prognostic tool in high-risk surgical patients
Human malarial disease: a consequence of inflammatory cytokine release
Malaria causes an acute systemic human disease that bears many similarities, both clinically and mechanistically, to those caused by bacteria, rickettsia, and viruses. Over the past few decades, a literature has emerged that argues for most of the pathology seen in all of these infectious diseases being explained by activation of the inflammatory system, with the balance between the pro and anti-inflammatory cytokines being tipped towards the onset of systemic inflammation. Although not often expressed in energy terms, there is, when reduced to biochemical essentials, wide agreement that infection with falciparum malaria is often fatal because mitochondria are unable to generate enough ATP to maintain normal cellular function. Most, however, would contend that this largely occurs because sequestered parasitized red cells prevent sufficient oxygen getting to where it is needed. This review considers the evidence that an equally or more important way ATP deficency arises in malaria, as well as these other infectious diseases, is an inability of mitochondria, through the effects of inflammatory cytokines on their function, to utilise available oxygen. This activity of these cytokines, plus their capacity to control the pathways through which oxygen supply to mitochondria are restricted (particularly through directing sequestration and driving anaemia), combine to make falciparum malaria primarily an inflammatory cytokine-driven disease
Public health interventions and epidemic intensity during the 1918 influenza pandemic
Nonpharmaceutical interventions (NPIs) intended to reduce infectious contacts between persons form an integral part of plans to mitigate the impact of the next influenza pandemic. Although the potential benefits of NPIs are supported by mathematical models, the historical evidence for the impact of such interventions in past pandemics has not been systematically examined. We obtained data on the timing of 19 classes of NPI in 17 U.S. cities during the 1918 pandemic and tested the hypothesis that early implementation of multiple interventions was associated with reduced disease transmission. Consistent with this hypothesis, cities in which multiple interventions were implemented at an early phase of the epidemic had peak death rates ≈50% lower than those that did not and had less-steep epidemic curves. Cities in which multiple interventions were implemented at an early phase of the epidemic also showed a trend toward lower cumulative excess mortality, but the difference was smaller (≈20%) and less statistically significant than that for peak death rates. This finding was not unexpected, given that few cities maintained NPIs longer than 6 weeks in 1918. Early implementation of certain interventions, including closure of schools, churches, and theaters, was associated with lower peak death rates, but no single intervention showed an association with improved aggregate outcomes for the 1918 phase of the pandemic. These findings support the hypothesis that rapid implementation of multiple NPIs can significantly reduce influenza transmission, but that viral spread will be renewed upon relaxation of such measures
Comparison Of New Photorefractive Composites Based On A Poly(Phenylene Vinylene) Derivative With Traditional Poly(n-vinylcarbazole) Composites
The performances of two classes of photorefractive polymer composites with low glass-transition temperatures (about 10-5 °C) are compared. One is based on the commonly used photoconductor poly(N-vinylcarbazole) (PVK), i.e., containing isolated charge-transport moieties for hopping. The other is based on the π-conjugated poly[1,4-phenylene-1,2-di(4-benzyloxyphenyl)vinylene] (DBOP-PPV), promising faster response times. The steady-state performance of the DBOP-PPV-based composites was found to be superior owing to (i) the larger internal free volume, allowing more efficient poling of the chromophores, and (ii) the slightly stronger space-charge field as a result of an increased trap density. By contrast, the dynamic response in a four-wave mixing experiment was similar to that of PVK-based composites despite the higher hole-drift mobility in conjugated PPV homopolymers than PVK. It was demonstrated that this is mainly a result of the poor charge-carrier generation efficiency.
Photo-physical and Redox-chemical NIR-Sensitivity Enhancement in Photorefractive Polymer Composites
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Development of a Hospital Medical Surge Preparedness Index using a national hospital survey
To generate a Hospital Medical Surge Preparedness Index that can be used to evaluate hospitals across the United States in regard to their capacity to handle patient surges during mass casualty events. Data from the American Hospital Association's annual survey, conducted from 2005 to 2014. Our sample comprised 6239 hospitals across all 50 states, with an annual average of 5769 admissions. An extensive review of the American Hospital Association survey was conducted and relevant variables applicable to hospital inpatient services were extracted. Subject matter experts then categorized these items according to the following subdomains of the "Science of Surge" construct: staff, supplies, space, and system. The variables within these categories were then analyzed through exploratory and confirmatory factor analyses, concluding with the evaluation of internal reliability. Based on the combined results, we generated individual (by hospital) scores for each of the four metrics and an overall score. The exploratory factor analysis indicated a clustering of variables consistent with the "Science of Surge" subdomains, and this finding was in agreement with the statistics generated through the confirmatory factor analysis. We also found high internal reliability coefficients, with Cronbach's alpha values for all constructs exceeding 0.9. A novel Hospital Medical Surge Preparedness Index linked to hospital metrics has been developed to assess a health care facility's capacity to manage patients from mass casualty events. This index could be used by hospitals and emergency management planners to assess a facility's readiness to provide care during disasters