bluuebunny/crossref_metadata_2025_split huggingface dataset:
Associations between ambient air pollutants exposure and case fatality rate of COVID-19: a multi-city ecological study in China
Authors: Zhang Tiantian , Zhao Guoli , Luo Li , Li Yongzhen , Shi Wenming 
Published: May 2020

AbstractBackgroundEnvironmental factors, including air pollution, can strongly impact on spatio-temporal patterns of infectious diseases outbreak. In this study, we aimed to investigate the association and correlation between ambient air pollutants and case fatality rate (CFR) of the novel coronavirus disease (COVID-19) in China.MethodsPublicly accessible data on COVID-19 average CFR were utilized in the data analysis. The ambient daily air pollutants including fine particulate matter (PM2.5), inhalable particles (PM10) and nitrogen dioxide (NO2) during the period from December 25, 2019 to March 5, 2020 were obtained from National Air Quality Real-time Publishing System of China. Ecological analysis was performed to explore the association and correlation between the cumulative average exposure of ambient air pollutants at different lag days (14 and 28 days) and average CFR in China outside Hubei and cities in Hubei province via model fitting.ResultsThe average case fatality rate was highest in Wuhan city (4.53%) and the cumulative average exposure of ambient PM2.5, PM10 and NO2 at lag 28 days was 55.8±12.1μg/m3, 66.8±9.2μg/m3, 20.7±4.4μg/m3, respectively in Hubei province during the study period. Ecological analysis showed that ambient PM2.5, PM10 and NO2 exposure at both lag 14 and 28 days was positively correlated with average CFR in China outside Hubei (province-level). For city-level analysis in Hubei, significant associations were only found between cumulative ambient NO2 exposure and average CFR(r=0.693 for Lag0-14, r=0.697 for Lag0-28, respectively) during the same period.ConclusionOur findings suggested ambient PM2.5, PM10 and NO2 exposure, especially at 28 lag days, positively associated with the case fatality rate of COVID-19 in China. These results could help provide guidance for identifying potential exposure window and preventing and controlling the epidemic.
Study of Hepatitis C Virus infection among multi-transfused patients with inherited β-globin synthesis gene defect, in the eastern region of India
Authors: Dutta Supradip , Biswas Aritra , Choudhury Promisree , Bakshi Sagnik , Chowdhury Prosanto , Bhattacharyya Maitreyee , Chakraborty Sharmistha , Dutta Shanta , Sadhukhan Provash C 
Published: May 2020

AbstractBackgroundPost transfusion acquired HCV infection is common in high-risk group individuals such as multi-transfused β-thalassemia patients who depend on regular blood transfusions. This study was conducted to determine epidemiology and distribution of HCV in multi-transfused β-thalassemia patients, in West Bengal, India.MethodsOver a span of six years blood samples were collected from HCV sero-reactive β-thalassemic patients and processed for viral RNA isolation followed by nested RT-PCR for qualitative viremia detection. HCV genotype was determined by amplifying partial HCV core gene by nested RT-PCR, DNA sequencing and using NCBI genotyping tools. Phylogenetic and phylogeographic studies were performed with online MEGA-X and BEAST 1.10.0 software respectively.ResultsOut of 917 multi-transfused HCV sero-reactive β-thalassemic patients, 598 (65.21%) were positive for HCV RNA while 250 (41.80%) had spontaneously cleared the virus. Female thalassemic patients and individuals belonging to ages 10-14 years had higher chances of spontaneous clearance. The most prevalent circulatory HCV genotype was 3a (78.11%) followed by 1b (12.20%). Phylogeographic analyses revealed that the 3a strains share similarity with Pakistan, Sri Lanka and Thailand whereas the 1b strains share similarity with Thailand, Vietnam, Russia and China.ConclusionThe prevalence of HCV infection is very high among Indian β-thalassemic patients, necessitates a critical look into the prevailing transfusion practices and requires implementation of more rigid donor screening criteria to decrease the rate of transfusion transmitted HCV infection, especially in multi-transfused thalassemic patients. The use of more sensitive NAT based assays for HCV detection in donor blood is a compressing need of the hour.
Perceived Stress and Psychological (Dis)Stress among Indian Endodontists During COVID19 Pandemic Lock down
Authors: Kumar Anil RN , Karumaran SC , Kattula Deepthi , Thavarajah Rooban , Anusa AM 
Published: May 2020

ASBTRACTBackgroundThe novel 2019 coronavirus(COVID-19) spreads by respiratory and aerosols. COVID19 driven pandemic causes panic, fear and stress among all strata of society. Like all other medical professions, dentists, particularly endodontists, who are highly exposed to aerosols would be exposed to stress. The aim of this study was to assess the (dis)stress among Indian endodontists and the factors that could influence the (dis)stress.MethodsFrom 8th April to 16th April 2020, we conducted an online survey in closed endodontic social media using snowball sampling technique, collecting basic demographic data, practice setting and relevant data. Psychological stress and perceived distress were collected through COVID-19 Peri-traumatic Distress Index (CPDI) and Perceived stress scale (PSS). Multinomial regression analysis was performed to estimate relative risk rate and P≤0.05 was considered significant.ResultsThis study had 586 Indian endodontists completing this survey across India. Of these, 311 (53.07%) were males, 325(55%) in the age group of 25-35 years, 64%in urban areas, 13.14% in solo-practice and a fourth of them were residents. Female endodontists had high perceived stress (RRR=2.46,P=0.01) as compared to males, as measured by PSS. Younger endodontists<25 years(RRR=9.75;P=0.002) and 25-35years (RRR=4.60;P=0.004) as compared with >45 years age-group had more distress. Exclusive consultants had RRR= 2.90, P=0.02, for mild-to-moderate distress as compared to normal. Factors driving this phenomenon are considered.ConclusionsDuring the lock down due to COVID-19, 1-in-2 Indian endodontists had distress, as measured by CPDI and 4-in-5 of them had perceived stress, as indicated by PSS. Our model identified certain factors driving the (dis)stress, which would help policy framers to initiate appropriate response.
Inference of causal relationships between sleep-related traits and 1,527 phenotypes using genetic data
Authors: García-Marín Luis M. , Campos Adrián I. , Martin Nicholas G. , Cuéllar-Partida Gabriel , Rentería Miguel E. 
Published: May 2020

AbstractStudy ObjectiveSleep is essential for both physical and mental health. There is an increasing interest in understanding how different factors shape individual variation in sleep duration, quality and patterns, or confer risk for sleep disorders. The present study aimed to identify novel causal relationships between sleep-related traits and other phenotypes, using a genetics-driven hypothesis-free approach not requiring longitudinal data.MethodsWe used genetic data and the latent causal variable (LCV) method to screen the phenome and infer causal relationships between seven sleep-related traits (insomnia, daytime dozing, easiness of getting up in the morning, snoring, sleep duration, napping, and morningness) and 1,527 different phenotypes.ResultsWe identify 84 significant causal relationships. Among other findings, poor health of musculoskeletal and connective tissue disorders increase insomnia risk and reduce sleep duration; depression-related traits increase insomnia and daytime dozing; insomnia, napping and snoring are affected by obesity and cardiometabolic traits and diseases; and working with asbestos, thinner, or glues increases insomnia, potentially through an increased risk of respiratory disease.ConclusionOverall, our results indicate that changes in sleep variables are predominantly the consequence, rather than the cause, of other underlying phenotypes and diseases. These insights could inform the design of future epidemiological and interventional studies in sleep medicine and research.
Mobility Reduction and Covid-19 Transmission Rates
Authors: Bergman Nittai K. , Fishman Ram 
Published: May 2020

AbstractAssessing the contribution of mobility restrictions to the control of Covid-19 diffusion is an urgent challenge of global import. We analyze the relation between transmission rates (estimated effective reproduction numbers) and societal mobility levels using fine-grained daily mobility data from Google and Apple in an international panel of 87 countries and a panel of all states in the United States. Reduced form regression estimates that flexibly control for time trends suggest that a 10 percentage point reduction in mobility is associated with a 0.04-0.09 reduction in the value of the effective reproduction number, R(t), depending on geographical region and modelling choice. According to these estimates, to avoid the critical value of R = 1, easing mobility restrictions may have to be limited to below pre-pandemic levels or delayed until other non-mobility related preventative measures reduce R to a level of 0.55–0.7 in Europe, a level of 0.64–0.76 in Asia, and a level of 0.8 in the United States. Given gaps in data availability and inference challenges, these estimates should be interpreted with caution.
A simple model to fit the time evolution of the daily death rate of Covid-19 in European Union countries
Authors: Beau Tristan , Browaeys Julien , Dadoun Olivier 
Published: May 2020

AbstractWe suggest a minimal model to describe the evolution of daily deaths due to Covid-19 in the European Union (EU) and UK, without any epidemiological hypothesis. Assuming current lockdown conditions were to remain in place, as of May 3rd 2020, this ad hoc fitting model is forecasting a total of 204 586 deaths in the EU. We could currently be at 2/3 of the total casualty count, and reach an overall death rate of one over 2 500 people.
Neutrophil calprotectin identifies severe pulmonary disease in COVID-19
Authors: Shi Hui , Zuo Yu , Yalavarthi Srilakshmi , Gockman Kelsey , Zuo Melanie , Madison Jacqueline A. , Blair Christopher , Woodward Wrenn , Lezak Sean P. , Lugogo Njira L. , Woods Robert J. , Lood Christian , Knight Jason S. , Kanthi Yogendra 
Published: May 2020

ABSTRACTSevere cases of coronavirus disease 2019 (COVID-19) are regularly complicated by respiratory failure. While it has been suggested that elevated levels of blood neutrophils associate with worsening oxygenation in COVID-19, it is unknown whether neutrophils are drivers of the thrombo-inflammatory storm or simple bystanders. To better understand the potential role of neutrophils in COVID-19, we measured levels of the neutrophil activation marker S100A8/A9 (calprotectin) in hospitalized patients and determined its relationship to severity of illness and respiratory status. Patients with COVID-19 (n=172) had markedly elevated levels of calprotectin in their blood. Calprotectin tracked with other acute phase reactants including C-reactive protein, ferritin, lactate dehydrogenase, and absolute neutrophil count, but was superior in identifying patients requiring mechanical ventilation. In longitudinal samples, calprotectin rose as oxygenation worsened. When tested on day 1 or 2 of hospitalization (n=94 patients), calprotectin levels were significantly higher in patients who progressed to severe COVID-19 requiring mechanical ventilation (8039 ± 7031 ng/ml, n=32) as compared to those who remained free of intubation (3365 ± 3146, p<0.0001). In summary, serum calprotectin levels track closely with current and future COVID-19 severity, implicating neutrophils as potential perpetuators of inflammation and respiratory compromise in COVID-19.
How to Flatten the post-lockdown epidemic trajectory
Authors: Sasikumar Roschen , Haridas Ajit 
Published: May 2020

AbstractPopulations are locked down during an epidemic to slow down the rate of infection so that epidemic trajectory is "flattened". This helps to keep cases at a manageable level. Given the enormous economic damage and misery caused by a lockdown, it is imperative to keep the lockdown period limited. A lockdown is useful only if it can be ensured that after the lockdown is lifted, the epidemic trajectory does not rise sharply again. We present here the results from a mathematical model of the epidemic which examines how the timing, strength and duration of the lockdown affects the post-lockdown epidemic trajectory. Our results show the following:A early lockdown (imposed when less than 1% of the population has been infected), of any reasonable duration, cannot prevent the return of the epidemic when the lockdown is lifted. The curve starts climbing soon after lifting the lockdown and reaches a peak of the same height as the no-lockdown curveThe post-lockdown trajectory can be flattened only if the lockdown is imposed after about 10% of the population has recovered after infection.The slope of the post-lockdown epidemic curve depends on the level of immunity built up in the population before and during the lockdown period. Application of lockdown around the inflexion point of the epidemic curve (the point of maximum slope of the curve) ensures that the post-lockdown curve is also flattened.
Angiotensin Converting Enzyme Inhibitors and Angiotensin Receptor Blockers and Outcome of COVID-19 : A Systematic Review and Meta-analysis
Authors: Abdulhak Aref A. Bin , Kashour Tarek , Noman Anas , Tlayjeh Haytham , Mohsen Ala , Al-Mallah Mouaz H. , Tleyjeh Imad M. 
Published: May 2020

AbstractImportanceThere is conflicting evidence about the role of angiotensin converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) in the pathogenesis and outcome of patients infected with acute severe respiratory syndrome coronavirus 2 (SARS-CoV-2) and growing public concerns about their use during this pandemic.ObjectiveWe sought to systematically review the literature and perform a meta-analysis about prior use of ACEI/ARBs and outcome of COVID-19 patients.Data sourceWe searched multiple data sources including PubMed, ClinicalTrial.org, and medrxiv.org from November 2019 through May 3, 2020.Study selectionAny study that reported on the role of ACEIs / ARBs and outcome of COIVD-19 is eligible. Two authors independently reviewed eligible studies and extracted data into a prespecified data collection form.Data synthesisAn inverse variance meta-analytic approach was used to pool adjusted odds ratios using a random effect model meta-analysis. I 2 test was used to assess in between studies heterogeneity. The Newcastle-Ottawa quality assessment scale was used to assess the quality of included studies.Main outcome and MeasuresThe association between the prior use of ACEIs / ARBs and the mortality among SARS-CoV-2 infected patients was assessed using pooled OR and 95% confidence interval. For studies that did not report adjusted effect estimates for mortality, we used their adjusted effect estimate of critical outcome to estimate another pooled OR for critical or fatal outcome and its 95% confidence interval.ResultsNine studies were included in this systematic review. The studies included a total of 58,615 patients infected with SARS-CoV-2. Prior use of ACEIs and/or ARBs was associated with a significant reduction of inpatient mortality among SARS-CoV-2 infected patients, with a pooled adjusted OR from 4 studies of 0.33, 95% CI [0.22, 0.49] with no between studies heterogeneity (12=0%) and with a significant reduction of critical or fatal outcome, with a pooled adjusted OR from 5 studies of 0.32, 95% CI [0.22, 0.46] (12 =32%).ConclusionOur meta-analysis suggests that use of ACEIs/ARBs is associated with a decreased risk of death or critical outcome among SARS-CoV-2 infected patients. This finding is limited by the observational nature of the included studies. However, it provides a reassurance to the public not to stop prescribed ACEIs/ARBs due to fear of severe COVID-19. It also calls upon investigators and ethics committees to reconsider the ongoing randomized trials of discontinuation of these drugs.
Suppression of Groups Intermingling as Appealing Option For Flattening and Delaying the Epidemiologic Curve While Allowing Economic and Social Life at Bearable Level During COVID-19 Pandemic
Authors: Bâldea Ioan 
Published: May 2020

AbstractIn this work, we simulate the COVID-19 pandemic dynamics in a population modeled as a network of groups wherein infection can propagate both via intra-group and via inter-group interactions. Our results emphasize the importance of diminishing the inter-group infections in the effort of substantial flattening and delaying of the epi(demiologic) curve with concomitant mitigation of disastrous economy and social consequences. To exemplify with a limiting case, splitting a population into m (say, 5 or 10) noninteracting groups while keeping intra-group interaction unchanged yields a stretched epidemiologic curve having the maximum number of daily infections reduced and postponed in time by the same factor m (5 or 10). More generally, our study suggests a practical approach to fight against SARS-CoV-2 virus spread based on population splitting into groups and minimizing intermingling between them. This strategy can be pursued by large-scale infrastructure reorganization of activity at different levels in big logistic units (e.g., large productive networks, factories, enterprises, warehouses, schools, (seasonal) harvest work). Importantly, unlike total lockdwon strategy, the proposed approach prevents economic ruin and keeps social life at a more bearable level than distancing everyone from anyone.
The disease-induced herd immunity level for Covid-19 is substantially lower than the classical herd immunity level
Authors: Britton Tom , Ball Frank , Trapman Pieter 
Published: May 2020

AbstractMost countries are suffering severely from the ongoing covid-19 pandemic despite various levels of preventive measures. A common question is if and when a country or region will reach herd immunityh. The classical herd immunity levelhCis defined ashC=1−1/R0, whereR0is the basic reproduction number, for covid-19 estimated to lie somewhere in the range 2.2-3.5 depending on country and region. It is shown here that the disease-induced herd immunity levelhD, after an outbreak has taken place in a country/region with a set of preventive measures put in place, is actually substantially smaller thanhC. As an illustration we show that ifR0=2.5 in an age-structured community with mixing rates fitted to social activity studies, and also categorizing individuals into three categories: low active, average active and high active, and where preventive measures affect all mixing rates proportionally, then the disease-induced herd immunity level ishD= 43% rather thanhC=1−1/2.5 = 60%. Consequently, a lower fraction infected is required for herd immunity to appear. The underlying reason is that when immunity is induced by disease spreading, the proportion infected in groups with high contact rates is greater than that in groups with low contact rates. Consequently, disease-induced immunity is stronger than when immunity is uniformly distributed in the community as in the classical herd immunity level.
Who can go back to work when the COVID-19 pandemic remits?
Authors: Hierro Luis Angel , Cantarero David , Patiño David , Arenaza Daniel Rodríguez-Pérez de 
Published: May 2020

AbstractThis paper seeks to determine which workers affected by lockdown measures can return to work when a government decides to apply lockdown exit strategies. This system, which we call Sequential Selective Multidimensional Decision (SSMD), involves deciding sequentially, by geographical areas, sectors of activity, age groups and immunity, which workers can return to work at a given time according to the epidemiological criteria of the country as well as that of a group of reference countries, used as a benchmark, that have suffered a lower level of lockdown de-escalation strategies. We apply SSMD to Spain, based on affiliation to the Social Security system prior to the COVID-19 pandemic, and conclude that 98.37% of the population could be affected. The proposed system makes it possible to accurately identify the target population for serological IgG antibody tests in the work field, as well as those affected by special income replacement measures due to lockdown being maintained over a longer period.
Age-adjusted associations between comorbidity and outcomes of COVID-19: a review of the evidence
Authors: Mason Kate E. , McHale Philip , Pennington Andy , Maudsley Gillian , Day Jennifer , Barr Ben 
Published: May 2020

ABSTRACTBackgroundCurrent evidence suggests that older people and people with underlying comorbidities are at increased risk of severe disease and death following hospitalisation with COVID-19. As comorbidity increases with age, it is necessary to understand the age-adjusted relationship between comorbidity and COVID-19 outcomes, in order to enhance planning capabilities and our understanding of COVID-19.MethodsWe conducted a rapid, comprehensive review of the literature up to 10 April 2020, to assess the international empirical evidence on the association between comorbidities and severe or critical care outcomes of COVID-19, after accounting for age, among hospitalised patients with COVID-19.ResultsAfter screening 579 studies, we identified seven studies eligible for inclusion and these were synthesised narratively. All were from China. The emerging evidence base mostly indicates that after adjustment for age (and in some cases other potential confounders), obesity, hypertension, diabetes mellitus, chronic obstructive airways disease (COPD), and cancer are all associated with worse outcomes. The largest study, using a large nationwide sample of COVID-19 patients in China, found that those with multiple comorbidities had more than twice the risk of a severe outcome or death compared with patients with no comorbidities, after adjusting for age and smoking (HR=2.59, 95% CI 1.61, 4.17).ConclusionsThis review summarises for clinicians, policymakers, and academics the most robust evidence to date on this topic, to inform the management of patients and control measures for tackling the pandemic. Given the intersection of comorbidity with ethnicity and social disadvantage, these findings also have important implications for health inequalities. As the pandemic develops, further research should confirm these trends in other settings outside China and explore mechanisms by which various underlying health conditions increase risk of severe COVID-19.
Bidirectional contact tracing dramatically improves COVID-19 control
Authors: Bradshaw William J. , Alley Ethan C. , Huggins Jonathan H. , Lloyd Alun L. , Esvelt Kevin M. 
Published: May 2020

AbstractContact tracing is critical to controlling COVID-19, but most protocols only “forward-trace” to notify people who were recently exposed. Using a stochastic branching-process model, we show that “bidirectional” tracing to identify infector individuals and their other infectees robustly improves outbreak control, reducing the effective reproduction number (Reff) by at least ∼0.3 while dramatically increasing resilience to low case ascertainment and test sensitivity. Adding smartphone-based exposure notification can further reduce Reff by 0.25, but only if nearly all smartphones can detect exposure events. Our results suggest that with or without digital approaches, implementing bidirectional tracing will enable health agencies to control COVID-19 more effectively without requiring high-cost interventions.