26 research outputs found
Inferring school district learning modalities during the COVID-19 pandemic with a hidden Markov model
In this study, learning modalities offered by public schools across the
United States were investigated to track changes in the proportion of schools
offering fully in-person, hybrid and fully remote learning over time. Learning
modalities from 14,688 unique school districts from September 2020 to June 2021
were reported by Burbio, MCH Strategic Data, the American Enterprise
Institute's Return to Learn Tracker and individual state dashboards. A model
was needed to combine and deconflict these data to provide a more complete
description of modalities nationwide.
A hidden Markov model (HMM) was used to infer the most likely learning
modality for each district on a weekly basis. This method yielded higher
spatiotemporal coverage than any individual data source and higher agreement
with three of the four data sources than any other single source. The model
output revealed that the percentage of districts offering fully in-person
learning rose from 40.3% in September 2020 to 54.7% in June of 2021 with
increases across 45 states and in both urban and rural districts. This type of
probabilistic model can serve as a tool for fusion of incomplete and
contradictory data sources in support of public health surveillance and
research efforts.Comment: 25 pages, 4 figure
Delivery of an Ebola Virus-Positive Stillborn Infant in a Rural Community Health Center, Sierra Leone, 2015.
We report the case of an Ebola virus (EBOV) RNA-negative pregnant woman who delivered an EBOV RNA-positive stillborn infant at a community health center in rural Sierra Leone, 1 month after the mother's last possible exposure. The mother was later found to be immunoglobulins M and G positive indicating previous infection. The apparent absence of Ebola symptoms and not recognizing that the woman had previous contact with an Ebola patient led health workers performing the delivery to wear only minimal personal protection, potentially exposing them to a high risk of EBOV infection. This case emphasizes the importance of screening for epidemiological risk factors as well as classic and atypical symptoms of Ebola when caring for pregnant women, even once they have passed the typical time frame for exposure and incubation expected in nonpregnant adults. It also illustrates the need for health-care workers to use appropriate personal protection equipment when caring for pregnant women in an Ebola setting
Tracking CNS and systemic sources of oxidative stress during the course of chronic neuroinflammation
The functional dynamics and cellular sources of oxidative stress are central to understanding MS pathogenesis but remain elusive, due to the lack of appropriate detection methods. Here we employ NAD(P)H fluorescence lifetime imaging to detect functional NADPH oxidases (NOX enzymes) in vivo to identify inflammatory monocytes, activated microglia, and astrocytes expressing NOX1 as major cellular sources of oxidative stress in the central nervous system of mice affected by experimental autoimmune encephalomyelitis (EAE). This directly affects neuronal function in vivo, indicated by sustained elevated neuronal calcium. The systemic involvement of oxidative stress is mirrored by overactivation of NOX enzymes in peripheral CD11b(+) cells in later phases of both MS and EAE. This effect is antagonized by systemic intake of the NOX inhibitor and anti-oxidant epigallocatechin-3-gallate. Together, this persistent hyper-activation of oxidative enzymes suggests an "oxidative stress memory" both in the periphery and CNS compartments, in chronic neuroinflammation
Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials.
Funder: laura and john arnold foundationBACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care
Quinolone nonsusceptibility among enteric pathogens isolated from international travelers - Foodborne Diseases Active Surveillance Network (FoodNet) and National Antimicrobial Monitoring System (NARMS), 10 United States sites, 2004 - 2014.
Gastrointestinal illnesses are the most frequently diagnosed conditions among returning U.S. travelers. Although most episodes of travelers' diarrhea do not require antibiotic therapy, fluoroquinolones (a type of quinolone antibiotic) are recommended for treatment of moderate and severe travelers' diarrhea as well as many other types of severe infection. To assess associations between quinolone susceptibility and international travel, we linked data about isolate susceptibility in NARMS to cases of enteric infections reported to FoodNet. We categorized isolates as quinolone-nonsusceptible (QNS) if they were resistant or had intermediate susceptibility to ≥1 quinolone. Among 1,726 travel-associated infections reported to FoodNet with antimicrobial susceptibility data in NARMS during 2004-2014, 56% of isolates were quinolone-nonsusceptible, of which most (904/960) were Campylobacter. International travel was associated with >10-fold increased odds of infection with quinolone-nonsusceptible bacteria. Most QNS infections were associated with travel to Latin America and the Caribbean (390/743; 52%); however, the greatest risk of QNS infection was associated with travel to Africa (120 per 1,000,000 passenger journeys). Preventing acquisition and onward transmission of antimicrobial-resistant enteric infections among travelers is critical
Exploration of risk factors for ceftriaxone resistance in invasive non-typhoidal Salmonella infections in western Kenya.
Multidrug-resistant non-typhoidal Salmonella (NTS) infection has emerged as a prominent cause of invasive infections in Africa. We investigated the prevalence of ceftriaxone-resistant invasive NTS infections, conducted exploratory analysis of risk factors for resistance, and described antimicrobial use in western Kenya. We conducted a secondary analysis of existing laboratory, epidemiology, and clinical data from three independent projects, a malaria vaccine trial, a central nervous system (CNS) study, and the International Emerging Infections Program morbidity surveillance (surveillance program) during 2009-2014. We calculated odds ratios (OR) with 95% confidence intervals (CI) for ceftriaxone-resistant NTS infections compared with ceftriaxone-susceptible infections. We surveyed hospitals, pharmacies, and animal drug retailers about the availability and use of antimicrobials. In total, 286 invasive NTS infections were identified in the three projects; 43 NTS isolates were ceftriaxone-resistant. The absolute prevalence of ceftriaxone resistance varied among these methodologically diverse projects, with 18% (16/90) of isolates resistant to ceftriaxone in the vaccine trial, 89% (16/18) in the CNS study, and 6% (11/178) in the surveillance program. Invasive ceftriaxone-resistant infections increased over time. Most ceftriaxone-resistant isolates were co-resistant to multiple other antimicrobials. Having an HIV-positive mother (OR = 3.7; CI = 1.2-11.4) and taking trimethoprim-sulfamethoxazole for the current illness (OR = 9.6, CI = 1.2-78.9) were significantly associated with acquiring ceftriaxone-resistant invasive NTS infection. Ceftriaxone and other antibiotics were widely prescribed; multiple issues related to prescription practices and misuse were identified. In summary, ceftriaxone-resistant invasive NTS infection is increasing and limiting treatment options for serious infections. Efforts are ongoing to address the urgent need for improved microbiologic diagnostic capacity and an antimicrobial surveillance system in Kenya