bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testing mobile air purifiers in a school classroom: Reducing the airborne transmission risk for SARS-CoV-2
Authors: Curtius J. , Granzin M. , Schrod J. 
Published: October 2020

ABSTRACTAirborne transmission of SARS-CoV-2 through virus-containing aerosol particles has been established as an important pathway for Covid-19 infection. Suitable measures to prevent such infections are imperative, especially in situations when a high number of persons convene in closed rooms. Here we tested the efficiency and practicability of operating four air purifiers equipped with HEPA filters in a high school classroom while regular classes were taking place. We monitored the aerosol number concentration for particles > 3 nm at two locations in the room, the aerosol size distribution in the range from 10 nm to 10 µm, PM10 and CO2 concentration. For comparison, we performed similar measurements in a neighboring classroom without purifiers. In times when classes were conducted with windows and door closed, the aerosol concentration was reduced by more than 90 % within less than 30 minutes when running the purifiers (air exchange rate 5.5 h-1). The reduction was homogeneous throughout the room and for all particle sizes. The measurements are supplemented by a calculation estimating the maximum concentration levels of virus-containing aerosol from a highly contagious person speaking in a closed room with and without air purifiers. Measurements and calculation demonstrate that air purifiers potentially represent a well-suited measure to reduce the risks of airborne transmission of SARS-CoV-2 substantially. Staying for two hours in a closed room with a highly infective person, we estimate that the inhaled dose is reduced by a factor of six when using air purifiers with a total air exchange rate of 5.7 h-1.Information ClassificationGeneral
Early transfusion of a large cohort of COVID-19 patients with high titer anti-SARS-CoV-2 spike protein IgG convalescent plasma confirms a signal of significantly decreased mortality
Authors: Salazar Eric , Christensen Paul A. , Graviss Edward A. , Nguyen Duc T. , Castillo Brian , Chen Jian , Lopez Bevin Valdez , Eagar Todd N. , Yi Xin , Zhao Picheng , Rogers John , Shehabeldin Ahmed , Joseph David , Masud Faisal , Leveque Christopher , Olsen Randall J. , Bernard David W. , Gollihar Jimmy , Musser James M. 
Published: October 2020

ABSTRACTCoronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 remains a global threat with few proven efficacious treatments. Transfusion of convalescent plasma collected from donors who have recovered from COVID-19 disease has emerged as a promising therapy and has been granted emergency use authorization by the U.S. Food and Drug Administration (FDA). We recently reported results from interim analysis of a propensity-score matched study suggesting that early treatment of COVID-19 patients with convalescent plasma containing high titer anti-spike protein receptor binding domain (RBD) IgG significantly decreases mortality. We here present results from 60-day follow up of our cohort of 351 transfused hospitalized patients. Prospective determination of ELISA anti-RBD IgG titer facilitated selection and transfusion of the highest titer units available. Retrospective analysis by the Ortho VITROS IgG assay revealed a median signal/cutoff (S/C) ratio of 24.0 for transfused units, a value far exceeding the recently FDA-required cutoff of 12.0 for designation of high titer convalescent plasma. With respect to altering mortality, our analysis identified an optimal window of 44 hours post-hospitalization for transfusing COVID-19 patients with high titer convalescent plasma. In the aggregate, the analysis confirms and extends our previous preliminary finding that transfusion of COVID-19 patients soon after hospitalization with high titer anti-spike protein RBD IgG present in convalescent plasma significantly reduces mortality.
CD8+T-cell landscape in Indigenous and non-Indigenous people restricted by influenza mortality-associated HLA-A*24:02 allomorph
Authors: Hensen Luca , Illing Patricia T. , Clemens E. Bridie , Nguyen Thi H.O. , Koutsakos Marios , van de Sandt Carolien E. , Mifsud Nicole A. , Nguyen Andrea , Szeto Christopher , Chua Brendon Y. , Halim Hanim , Rizzetto Simone , Luciani Fabio , Loh Liyen , Grant Emma J. , Saunders Phillipa M. , Brooks Andrew G , Rockman Steve , Kotsimbos Tom C. , Cheng Allen C. , Richards Michael , Westall Glen P. , Wakim Linda M. , Loudovaris Thomas , Mannering Stuart I. , Elliott Michael , Tangye Stuart G. , Jackson David C , Flanagan Katie L , Rossjohn Jamie , Gras Stephanie , Davies Jane , Miller Adrian , Tong Steven Y.C. , Purcell Anthony W. , Kedzierska Katherine 
Published: October 2020

ABSTRACTIndigenous people worldwide are at high-risk of developing severe influenza disease. HLA-A*24:02 allele, highly prevalent in Indigenous populations, is associated with influenza-induced mortality, although the basis for this association is unclear. We defined CD8+T-cell immune landscapes against influenza A (IAV) and B (IBV) viruses in HLA-A*24:02-expressing Indigenous and non-Indigenous individuals, human tissues, influenza-infected patients and HLA-A*24:02-transgenic mice. We identified immunodominant protective CD8+T-cell epitopes, one towards IAV and six towards IBV, with A24/PB2550-558-specific CD8+T-cells cells being cross-reactive between IAV and IBV. Memory CD8+T-cells towards these specificities were present in blood (CD27+CD45RA-phenotype) and tissues (CD103+CD69+phenotype) of healthy subjects, and effector CD27-CD45RA-PD-1+CD38+CD8+T-cells in IAV/IBV patients. Our data present the first evidence of influenza-specific CD8+T-cell responses in Indigenous Australians, and advocate for T-cell-mediated vaccines that target and boost the breadth of IAV/IBV-specific CD8+T-cells to protect high-risk HLA-A*24:02-expressing Indigenous and non-Indigenous populations from severe influenza disease.One Sentence SummaryInfluenza-specific CD8+T-cell specificities restricted by HLA-A*24:02.
Validation of self-collected buccal swab and saliva as a diagnostic tool for COVID-19
Authors: Ku Chee Wai , Shivani Durai , Kwan Jacqueline Q T , Loy See Ling , Erwin Christina , Ko Karrie K K , Ng Xiang Wen , Oon Lynette , Thoon Koh Cheng , Kalimuddin Shirin , Chan Jerry KY 
Published: October 2020

ABSTRACTBackgroundEffective management of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) requires large-scale testing. Collection of nasopharyngeal swab (NPS) by healthcare workers (HCW) is currently used to diagnose SARS-CoV-2, which increases the risk of transmission to HCWs. Self-administered saliva and buccal swabs are convenient, painless and safe alternative sample collection methods.MethodsA cross-sectional single centre study was conducted on 42 participants who were tested positive for SARS-CoV-2 via NPS within the past 7 days. A self-collected saliva and buccal swab and a HCW-collected NPS were obtained. Real-time polymerase chain reaction (RT-PCR) was performed and cycle threshold (CT) values were obtained. Positive percent agreement (PPA), negative percent agreement (NPA) and overall agreement (OA) were calculated for saliva and buccal swabs, as compared with NPS.ResultsAmong the 42 participants, 73.8% (31/42) tested positive via any one of the 3 tests. With reference to NPS, the saliva test had PPA 66.7%, NPA 91.7% and OA 69.0%. The buccal swab had PPA 56.7%, NPA 100% and OA 73.8%. Presence of symptoms improved diagnostic accuracy. There was no statistically significant association between CT values and duration of symptom onset within the first 12 days of symptoms for all three modalities.ConclusionSelf-collected saliva tests and buccal swabs have only moderate agreement with HCW-collected NPS swabs. Primary screening for SARS-CoV-2 may be performed with a saliva test or buccal swab, with a negative test warranting a confirmatory NPS to avoid false negatives. This combined strategy minimizes discomfort and reduces the risk of spread to the community and HCWs.
The Impact of COVID-19 on the Management of Heart Failure -A United Kingdom Patient Questionnaire Study
Authors: Sankaranarayanan R , Hartshorne-Evans N , Redmond-Lyon S , Wilson J , Essa H , Gray A , Clayton L , Barton C , Ahmed FZ , Cunnington C , Satchithananda DK , Murphy C 
Published: October 2020

AbstractAimThe coronavirus disease 2019 (COVID-19) pandemic has created significant challenges to healthcare globally, necessitating rapid restructuring of service provision. This questionnaire survey was conducted amongst adult heart failure (HF) patients in the United Kingdom (UK), to understand the impact of COVID-19 upon HF services.Methods and ResultsThe survey was conducted by the Pumping Marvellous Foundation (PMF), a UK HF patient charity. “Survey Monkey” was used to disseminate the questionnaire in the PMF’s online patient group and in 10 UK hospitals (out-patient hospital and community HF clinics). 1050 responses were collected (693/1050-66% women); 55% (579/1050) were aged over 60 years. Anxiety level was significantly higher regarding COVID19 (mean 7±2.5 on anxiety scale of 0 to 10) compared to anxiety regarding HF (6.1±2.4; p<0.001). Anxiety was higher amongst patients aged ≤60 years about HF (6.3±2.2 versus 5.9±2.5 in those aged >60 years; p=0.005) and COVID-19 (7.3±2.3 versus 6.7±2.6 those aged >60 years; p<0.001). 65% respondents (686/1050) reported disruption to HF appointments (cancellation or postponement) during the lockdown period. 37% reported disruption to medication prescription services and 34% reported inability to access their HF teams promptly. 32% expressed reluctance to attend hospital (25% stated they would only attend hospital if there was no alternative and 7% stated that they would not attend hospital at all).ConclusionsThe COVID-19 pandemic has caused significant anxiety amongst HF patients regarding COVID-19 and HF. Cancellation or postponement of scheduled clinic appointments, investigations, procedures, prescription and monitoring services were implicated as sources of anxiety.
Diagnostic performance of the combined nasal and throat swab in patients admitted to hospital with suspected COVID-19
Authors: Lee Kuan Ken , Doudesis Dimitrios , Ross Daniella A. , Bularga Anda , MacKintosh Claire L. , Koch Oliver , Johannessen Ingolfur , Templeton Kate , Jenks Sara , Chapman Andrew R. , Shah Anoop S.V. , Anand Atul , Perry Meghan R. , Mills Nicholas L. ,   on behalf of the DataLoch COVID-19 Collaboration
Published: October 2020

AbstractBackgroundAccurate diagnosis in patients with suspected coronavirus disease 2019 (COVID-19) is essential to guide treatment and limit spread of the virus. The combined nasal and throat swab is used widely, but its diagnostic performance is uncertain.MethodsIn a prospective, multi-centre, cohort study conducted in secondary and tertiary care hospitals in Scotland, we evaluated the combined nasal and throat swab with reverse transcriptase-polymerase chain reaction (RT-PCR) for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in consecutive patients admitted to hospital with suspected COVID-19. Diagnostic performance of the index and serial tests was evaluated for a primary outcome of confirmed or probable COVID-19, and a secondary outcome of confirmed COVID-19 on serial testing. The diagnosis was adjudicated by a panel, who recorded clinical, laboratory and radiological features blinded to the test results.ResultsWe enrolled 1,369 consecutive patients (68 [53-80] years, 47% women) who underwent a total of 3,822 tests (median 2 [1-3] tests per patient). The primary outcome occurred in 36% (496/1,369), of whom 65% (323/496) and 35% (173/496) had confirmed and probable COVID-19, respectively. The index test was positive in 255/496 (51%) patients with the primary outcome, giving a sensitivity and specificity of 51.4% (95% confidence interval [CI] 48.8 to 54.1%) and 99.5% (95% CI 99.0 to 99.8%). Sensitivity increased in those undergoing 2, 3 or 4 tests to 60.1% (95% CI 56.7 to 63.4%), 68.3% (95% CI 64.0 to 72.3%) and 77.6% (95% CI 72.7 to 81.9%), respectively. The sensitivity of the index test was 78.9% (95% CI 74.4 to 83.2%) for the secondary outcome of confirmed COVID-19 on serial testing.ConclusionsIn patients admitted to hospital, a single combined nasal and throat swab with RT-PCR for SARS-CoV-2 has excellent specificity, but limited diagnostic sensitivity for COVID-19. Diagnostic performance is significantly improved by repeated testing.
A systematic review of the knowledge, attitudes, and practices of physicians, health workers, and the general population about Coronavirus disease 2019 (COVID-19)
Authors: Saadatjoo Saeede , Miri Maryam , Hassanipour Soheil , Ameri Hosein , Arab-Zozani Morteza 
Published: October 2020

AbstractBackgroundUnderstanding people, physicians, and healthcare workers’ knowledge, attitude, and practices (KAPs) can help to achieve the outcomes of planned behavior. The aim of this study was to investigate and synthesize the current evidence on KAPs regarding COVID-19.MethodsWe conducted a systematic search on PubMed/LitCovid, Scopus, and Web of Sciences databases for papers in the English language only, up to 1 Jul 2020. We used the Joanna Briggs Institute (JBI) checklist developed for cross-sectional studies to appraise the quality of the included studies. All stages of the review conducted by two independent reviewers and potential discrepancies solved with a consultation with a third reviewer. We reported the result as number and percentage. PROSPERO registration code: (CRD42020186755).ResultsFifty-two studies encompassing 49786 participants were included in this review. 45.76% of the participants were male. The mean age of the participants was 32.6 years. 44.2% of the included studies were scored as good quality, 46.2% as fair quality, and remaining (9.6%) as low quality. 30.76% examined all three components of the KAPs model. The knowledge component was reported as good, fair, and poor in 59%, 34%, and 7%, respectively. Of the studies that examined the attitude component, 82% reported a positive attitude, 11% a fairly positive attitude, and 7% a negative attitude. For the practice component, 52% reported good practice, 44% fair practice, and 4% poor practice.ConclusionThis systematic review showed that the overall KAP components in the included studies were at an acceptable level. In general, knowledge was at a good level, the attitude was positive and practice was at a fairly good level. Using an integrated international system can help better evaluate these components and compare them between countries.
Strategies for infection control and prevalence of anti-SARS-CoV-2 IgG in 4,554 employees of a university hospital in Munich, Germany
Authors: Erber Johanna , Kappler Verena , Haller Bernhard , Mijočević Hrvoje , Galhoz Ana , da Costa Clarissa Prazeres , Gebhardt Friedemann , Graf Natalia , Hoffmann Dieter , Thaler Markus , Lorenz Elke , Roggendorf Hedwig , Kohlmayer Florian , Henkel Andreas , Menden Michael P , Ruland Jürgen , Spinner Christoph D , Protzer Ulrike , Knolle Percy , Lingor Paul ,   on behalf of the SeCoMRI Study Group
Published: October 2020

AbstractBackgroundHospital staff are at high risk of infection during the coronavirus disease (COVID-19) pandemic. We analysed the exposure characteristics, efficacy of protective measures, and transmission dynamics in this hospital-wide prospective seroprevalence study.Methods and FindingsOverall, 4554 individuals were tested for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG antibodies using a chemiluminescent immunoassay. Individual risk factors, use of personal protective equipment (PPE), occupational exposure, previous SARS-CoV-2 infection, and symptoms were assessed using a questionnaire and correlated to anti-SARS-CoV-2 IgG antibody titres and PCR testing results. Odds ratios with corresponding exact 95% confidence intervals were used to evaluate associations between individual factors and seropositivity. Spatio-temporal trajectories of SARS-CoV-2-infected patients and staff mobility within the hospital were visualised to identify local hotspots of virus transmission.The overall seroprevalence of anti-SARS-CoV-2-IgG antibody was 2.4% [95% CI 1.9–2.9]. Patient-facing staff, including those working in COVID-19 areas, had a similar probability of being seropositive as non-patient-facing staff. Prior interaction with SARS-CoV-2-infected co-workers or private contacts and unprotected exposure to COVID-19 patients increased the probability of seropositivity. Loss of smell and taste had the highest positive predictive value for seropositivity. The rate of asymptomatic SARS-CoV-2 infections was 25.9%, and higher anti-SARS-CoV-2 IgG antibody titres were observed in symptomatic individuals. Spatio-temporal hotspots of SARS-CoV-2-positive staff and patients only showed partial overlap.ConclusionsPatient-facing work in a healthcare facility during the SARS-CoV-2 pandemic may be safe if adequate PPE and hygiene measures are applied. The high numbers of asymptomatic SARS-CoV-2 infections that escaped detection by symptomatic testing underline the value of cross-sectional seroprevalence studies. Unprotected contact is a major risk factor for infection and argues for the rigorous implementation of hygiene measures.
Artificial intelligence-driven real-time 3D surface quantification of Barrett’s oesophagus for risk stratification and therapeutic response monitoring
Authors: Ali Sharib , Bailey Adam , East James E. , Leedham Simon J. , Haghighat Maryam ,   TGU Investigators, Lu Xin , Rittscher Jens , Braden Barbara 
Published: October 2020

BACKGROUND & AIMSBarrett’s epithelium measurement using widely accepted Prague C&M criteria is highly operator dependent. By reconstructing the surface of the Barrett’s area in 3D from endoscopy video, we propose a novel methodology for measuring the C&M score automatically. This 3D reconstruction provides an extended field of view and also allows to precisely quantify the Barrett’s area including islands. We aim to assess the accuracy of the extracted measurements from phantom and demonstrate their clinical usability.METHODSAdvanced deep learning techniques are utilised to design estimators for depth and camera pose required to map standard endoscopy video to a 3D surface model. By segmenting the Barrett’s area and locating the position of the gastro-oesophageal junction (GEJ) we measure C&M scores and the Barrett’s oesophagus areas (BOA). Experiments using a purpose-built 3D printed oesophagus phantom and high-definition video from 98 patients scored by an expert endoscopist are used for validation.RESULTSEndoscopic phantom video data demonstrated a 95 % accuracy with a marginal ± 1.8 mm average deviation for C&M and island measurements, while for BOA we achieved nearly 93 % accuracy with only ± 1.1 cm2 average deviation compared to the ground-truth measurements. On patient data, the C&M measurements provided by our system concord with the reference provided by expert upper GI endoscopists.CONCLUSIONSThe proposed methodology is suitable for extracting Prague C&M scores automatically with a high degree of accuracy. Providing an accurate measurement of the entire Barrett’s area provides new opportunities for risk stratification and the assessment of therapy response.
Fixation beats – a novel marker for reaching the left bundle branch area during deep septal lead implantation
Authors: Jastrzębski Marek , Kiełbasa Grzegorz , Moskal Paweł , Bednarek Agnieszka , Kusiak Aleksander , Sondej Tomasz , Bednarski Adam , Rajzer Marek , Vijayaraman Pugazhendhi 
Published: October 2020

AbstractIntroductionOne of the challenges of left bundle branch (LBB) pacing is to place the pacing lead deep enough in the septum to obtain capture of the LBB, yet not too deep to avoid perforation. We hypothesized that the occurrence of the ectopic beats of qR/rsR’ morphology in V1 lead (fixation beats) during the lead fixation would predict that the final desired intraseptal lead depth was just reached, while the lack of fixation beats would indicate too shallow position, and need for more lead rotations.MethodsConsecutive patients during LBB pacing device implantation were analyzed retrospectively and then prospectively with respect to the occurrence of the fixation beats during each episode of lead rotation. We compared the presence of fixation beats during the lead rotation event directly before the LBB capture area depth was reached versus during the events before intermediate/unsuccessful positions.ResultsA total of 339 patients and 1278 lead rotation events were analyzed. In the retrospective phase, the fixation beats were observed in 327/339 of final lead positions and in 9/939 of intermediate lead positions (p<0.001). The sensitivity, specificity, positive and negative predictive value of the LBB area fixation beats as a marker for reaching the LBB capture area was 96.4%, 99.0%, 97.3% and 99.0%, respectively. In the prospective, fixation-beats-guided, implantation phase the fixation beats were observed in all patients and only at the LBB capture depth.ConclusionsMonitoring fixation beats during deep septal lead deployment can facilitate the procedure and possibly increase the safety of lead implantation.