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1.
J Formos Med Assoc ; 2022.
Article in English | ScienceDirect | ID: covidwho-2031449
2.
J Biomed Sci ; 29(1):68, 2022.
Article in English | PubMed | ID: covidwho-2021289

ABSTRACT

The novel coronavirus disease (COVID-19) pandemic remains a global public health crisis, presenting a broad range of challenges. To help address some of the main problems, the scientific community has designed vaccines, diagnostic tools and therapeutics for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The rapid pace of technology development, especially with regard to vaccines, represents a stunning and historic scientific achievement. Nevertheless, many challenges remain to be overcome, such as improving vaccine and drug treatment efficacies for emergent mutant strains of SARS-CoV-2. Outbreaks of more infectious variants continue to diminish the utility of available vaccines and drugs. Thus, the effectiveness of vaccines and drugs against the most current variants is a primary consideration in the continual analyses of clinical data that supports updated regulatory decisions. The first two vaccines granted Emergency Use Authorizations (EUAs), BNT162b2 and mRNA-1273, still show more than 60% protection efficacy against the most widespread current SARS-CoV-2 variant, Omicron. This variant carries more than 30 mutations in the spike protein, which has largely abrogated the neutralizing effects of therapeutic antibodies. Fortunately, some neutralizing antibodies and antiviral COVID-19 drugs treatments have shown continued clinical benefits. In this review, we provide a framework for understanding the ongoing development efforts for different types of vaccines and therapeutics, including small molecule and antibody drugs. The ripple effects of newly emergent variants, including updates to vaccines and drug repurposing efforts, are summarized. In addition, we summarize the clinical trials supporting the development and distribution of vaccines, small molecule drugs, and therapeutic antibodies with broad-spectrum activity against SARS-CoV-2 strains.

3.
Journal of Breath Research ; 02:02, 2022.
Article in English | MEDLINE | ID: covidwho-2017581

ABSTRACT

BACKGROUND: SARS-CoV-2 has caused a tremendous threat to global health. PCR and antigen testing have played a prominent role in the detection of SARS-CoV-2-infected individuals and disease control. An efficient, reliable detection tool is still urgently needed to halt the global COVID-19 pandemic. Recently, FDA emergency approved VOC as an alternative test for COVID-19 detection. METHODS AND MATERIALS: In this case-control study, we prospectively and consecutively recruited 95 confirmed COVID-19 patients and 106 healthy controls in the designated hospital for treatment of COVID-19 patients in Shenzhen, China. Exhaled breath samples were collected and stored in customized bags and then detected by HPPI-TOFMS for volatile organic components (VOCs). Machine learning (ML) algorithms were employed for COVID-19 detection model construction. Participants were randomly assigned in a 5:2:3 ratio to the training, validation, and blinded test sets. The sensitivity (SEN), specificity (SPE), and other general metrics were employed for the VOCs based COVID-19 detection model performance evaluation. RESULTS: The VOCs based COVID-19 detection model achieved good performance, with a SEN of 92.2% (95% CI: 83.8%, 95.6%), a SPE of 86.1% (95% CI: 74.8%, 97.4%) on blinded test set. Five potential VOC ions related to COVID-19 infection were discovered, which are significantly different between COVID-19 infected patients and controls. CONCLUSIONS: This study evaluated a simple, fast, non-invasive VOCs-based COVID-19 detection method and demonstrated that it has good sensitivity and specificity in distinguishing COVID-19 infected patients from controls. It has great potential for fast and accurate COVID-19 detection.

4.
Natural Product Communications ; 17(8), 2022.
Article in English | EMBASE | ID: covidwho-1986555

ABSTRACT

Objectives: Coronavirus disease 2019 (COVID-19) has had a global impact and is spreading quickly. ChuanKeZhi injection (CKZI) is widely used in asthma patients. In this paper, we aimed to explore active compounds of CKZ and determine potential mechanisms against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through network pharmacology, molecular docking and dynamic simulation studies. Materials and Methods: We used the Systematic Pharmacology Database and Analysis Platform of Traditional Chinese Medicine (TCMSP) to screen active compounds and potential target proteins of CKZ. COVID-19 target genes were screened via the American National Center for Biotechnology Information (NCBI) gene database and human gene database (GeenCards). The protein interaction network was constructed by the Protein Interaction Network Database (Search Tool for the Retrieval of Interacting Genes/Proteins (STRING)) platform. GO enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed by the Metascape database. The main active compounds of CKZ were docked with angiotensin-converting enzyme 2 (ACE2), spike protein S1, and SARS-CoV-2-3CL pro and also docked with hub targets. We performed molecular dynamics (MD) simulation studies for validation. Results: We finally obtained 207 CKZ potential targets and 4681 potential COVID-19 targets. Key targets included mainly AKT1, TNF, IL6, VEGFA, IL1B, TP53, JUN, CASP3, etc. There were 217 Gene Ontology (GO) items in the GO enrichment analysis (p < 0.05). The main KEGG pathways included the advanced glycation end products (AGE)- receptor for AGE (RAGE) signalling pathway in diabetic complications, rheumatoid arthritis, chemical carcinogenesis-receptor activation, alcoholic liver disease, etc. Molecular docking and dynamics simulation studies both exhibited great binding capacity. Conclusions: Network pharmacology, molecular docking and dynamics simulation studies were used to identify the potential and key targets, pharmacological functions, and therapeutic mechanisms of CKZI in the treatment of COVID-19. CKZI may be an effective and safe drug in COVID-19 treatment. However, further work is needed for validation.

5.
Engineering Construction and Architectural Management ; : 19, 2022.
Article in English | Web of Science | ID: covidwho-1868459

ABSTRACT

Purpose The unprecedented SARS-CoV-2 (COVID-19) pandemic has further constrained the budgets of governments worldwide for delivering their much-needed infrastructure. Consequently, public-private partnerships (PPPs), with the private sector's investment and ingenuity, would appear to be an increasingly popular alternative. Value for money (VfM) has become the major criterion for evaluating PPPs against the traditional public sector procurement and, however, is plagued with controversy. Hence, it is important that governments compare and contrast their practice with similar and disparate bodies to engender best practice. This paper, therefore, aims to understand governments' assessment context and provide a cross-continental comparison of their VfM assessment. Design/methodology/approach Faced with different domestic contexts (e.g. aging infrastructure, population growth, and competing demands on finance), governments tend to place different emphases when undertaking the VfM assessment. In line with the theory of boundary spanning, a cross-continental comparison is conducted between three of the most noticeable PPP markets (i.e. the United Kingdom, Australia and China) about their VfM assessment. The institutional level is interpreted by a social, economic and political framework, and the methodological level is elucidated through a qualitative and quantitative VfM assessment. Findings There are individual institutional characteristics that have shaped the way each country assesses VfM. For the methodological level, we identify that: (1) these global markets use a public sector comparator as the benchmark in VfM assessment;(2) ambiguous qualitative assessment is conducted only against PPPs to strengthen their policy development;(3) Australia's priority is in service provision whereas that of the UK and China is project finance and production;and (4) all markets are seeking an amelioration of existing controversial VfM assessments so that purported VfM relates to project lifecycles. As such, an option framework is proposed to make headway towards a sensible selection of infrastructure procurement approaches in the post COVID-19 era. Originality/value This study addresses a current void of enhancing the decision-making process for using PPPs within today's changing environment and then opens up an avenue for future empirical research to examine the option framework and ensuing VfM decisions. Practically, it presents a holistic VfM landscape for public sector procurers that aim to engage with PPPs for their infrastructure interventions.

6.
Preprint in English | medRxiv | ID: ppmedrxiv-22275279

ABSTRACT

BackgroundThe limited variation observed among SARS-CoV-2 consensus sequences makes it difficult to reconstruct transmission linkages in outbreak settings. Previous studies have recovered variation within individual SARS-CoV-2 infections but have not yet measured the informativeness of within-host variation for transmission inference. MethodsWe performed tiled amplicon sequencing on 307 SARS-CoV-2 samples from four prospective studies and combined sequence data with household membership data, a proxy for transmission linkage. ResultsConsensus sequences from households had limited diversity (mean pairwise distance, 3.06 SNPs; range, 0-40). Most (83.1%, 255/307) samples harbored at least one intrahost single nucleotide variant (iSNV; median: 117; IQR: 17-208), when applying a liberal minor allele frequency of 0.5% and prior to filtering. A mean of 15.4% of within-host iSNVs were recovered one day later. Pairs in the same household shared significantly more iSNVs (mean: 1.20 iSNVs; 95% CI: 1.02-1.39) than did pairs in different households infected with the same viral clade (mean: 0.31 iSNVs; 95% CI: 0.28-0.34), a signal that increases with increasingly liberal thresholds. ConclusionsAlthough only a subset of within-host variation is consistently shared across likely transmission pairs, shared iSNVs may augment the information in consensus sequences for predicting transmission linkages.

7.
Open Forum Infectious Diseases ; 8(SUPPL 1):S805-S806, 2021.
Article in English | EMBASE | ID: covidwho-1746279

ABSTRACT

Background. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection elicits antibodies (Abs) that bind several viral proteins such as the spike entry protein and the abundant nucleocapsid (N) protein. We examined convalescent sera collected through 6 months (~24wks) post-SARS-CoV-2 infection in children to evaluate changes in neutralization potency and N-binding. Methods. Outpatient, hospitalized, and community recruited volunteers < 18 years with COVID-19 were enrolled in a longitudinal study at Seattle Children's Hospital. Analysis includes symptomatic and asymptomatic children with laboratory-confirmed SARS-CoV-2 infection who provided blood samples at approximately 4wks (range: 2-18wks, IQR:4-8wks) and 24 wks (range: 23-35wks, IQR:25-27wks) after diagnosis. We measured neutralizing Ab using an in-house pseudoneutralization assay and anti-N binding Ab using the Abbott Architect assay. Results. Of 32 children enrolled between April 2020 and January 2021, 27 had no underlying immunocompromised state and 25 of these 27 children had symptomatic disease. Ten of 27 had a > 2-fold decrease neutralization titers between 4 and 24wks (most were < 10-fold);12 had < 2-fold change;and 5 had neutralization titers that increased > 2-fold over time (Fig. 1A). All but one of these 27 children had detectable neutralizing activity at 24wks. Anti-N Abs were assessed for 25 children at 4wks and 17 children at 24wks (data pending for 14 samples);all children with paired samples had a > 1.75-fold Abbott index reduction at 24wks, and 5 children had no detectable anti-N Abs by 24wks (Fig. 2A). An additional 5 children with symptomatic disease had complicating immunosuppression or multiple blood transfusions;2 had decreasing neutralizing titers, 2 increased, and 1 had no change (Fig. 1B). Anti-N Abs were undetectable for one child by 24wks (data pending for 4 samples) (Fig. 2B). No participants received COVID-19 vaccine. Conclusion. We show neutralizing Abs wane to a small degree over 24wks post-SARS-CoV-2 infection and remain detectable in most children. In contrast, anti-N Abs decreased, becoming undetectable in some children by 24wks. These findings add to understanding of the natural history of SARS-CoV-2 immunity in children.

8.
Jisuanji Jicheng Zhizao Xitong/Computer Integrated Manufacturing Systems, CIMS ; 28(1):242-257, 2022.
Article in Chinese | Scopus | ID: covidwho-1698657

ABSTRACT

COVID-19 has an impact on the global supply chain, which is mainly manifested in the simultaneous interruption of production capacity and demand. To explore the impact of government subsidy strategies on recovery in the context of supply chain interruption, the low-demand products during the epidemic were used as the research object, and the government's choice of subsidies for production capacity and demand interruption as a recovery strategy. The cumulative profit of supply chain members was taken as the recovery index, and system dynamics was used to construct the "manufacturer-distribution center" secondary supply chain. The changes in cumulative profits for different subsidy options were simulate under partial and complete interruption scenarios. The simulation results showed that the choice of government subsidy strategies under different interruption scenarios had different effects on the supply chain recovery effect. In the scenario of partial demand interruption, government subsidies for manufacturers with interrupted production capacity would make the supply chain recovery better. In the scenario of complete demand interruption, government subsidies for distribution centers with interrupted demand would make the supply chain recovery better. © 2022, Editorial Department of CIMS. All right reserved.

9.
2nd International Symposium on Artificial Intelligence for Medicine Sciences, ISAIMS 2021 ; : 545-550, 2021.
Article in English | Scopus | ID: covidwho-1613112

ABSTRACT

The outbreak of COVID-19 in 2020 has had a serious impact on society and drawn the attention of all sectors of society to major emergency public security incidents. So this study focused on the social distance which is one of the most effective methods to reduce the transmission rate of the epidemic to conduct research. In order to visually describe the effect of social distance obedience behavior, we use Anylogic to simulate the subway station with high pedestrian traffic in daily life and visualize the process and rate of transmission. Social distance was introduced as a primary variable, mask-wearing rate as a secondary variable, and the simulation set the movement trajectory of pedestrians and used the "controlled variable method"to analyze their effects on infection. The results show that both maintaining a social distance of more than 1.25 meters and wearing a mask rate of more than 70% can effectively inhibit the spread of the epidemic, and the combined effect of both is more effective in infection control. © 2021 ACM.

10.
Dermatology Online Journal ; 26(8), 2020.
Article in English | EMBASE | ID: covidwho-1580089

ABSTRACT

Dermatologic surgeons are at increased risk of contracting coronavirus disease 2019 (COVID-19). At time of writing, there is no published standard for the role of pre-operative testing or the use of smoke evacuators, and personal protective equipment (PPE) in dermatologic surgery. Risks and safety measures in otolaryngology, plastic surgery, and ophthalmology are discussed. In Mohs surgery, cases involving nasal or oral mucosa are highest risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission;pre-operative testing and N95 masks should be urgently prioritized for these cases. Other key safety recommendations include strict control of patient droplets and expanded pre-clinic screening. Dermatologic surgeons are encouraged to advocate for appropriate pre-operative tests, smoke evacuators, and PPE. Future directions would include national consensus guidelines with continued refinement of safety protocols.

13.
Open forum infectious diseases ; 8(Suppl 1):293-293, 2021.
Article in English | EuropePMC | ID: covidwho-1563806

ABSTRACT

Background While pediatric cases of COVID-19 are at low risk for adverse events, schoolchildren should be considered for surveillance as they can become infected at school and serve as sources of household or community transmission. Our team assessed the feasibility of young children self-collecting SARS-CoV-2 samples for surveillance testing in an educational setting. Methods Students at a K-8 school were tested weekly for SARS-CoV-2 from September 2020 - June 2021. Error rates were collected from September 2020 - January 2021. Clinical staff provided all students with instructions for anterior nares specimen self-collection and then observed them to ensure proper technique. Instructions included holding the sterile swab while making sure not to touch the tip, inserting the swab into their nostril until they start to feel resistance, and rubbing the swab in four circles before repeating the process in their other nostril. An independent observer timed random sample self-collections from April - June 2021. Results 2,590 samples were collected from 209 students during the study period when data on error rates were collected. Errors occurred in 3.3% of all student encounters (n=87). Error rates over time are shown in Figure 1, with the highest rate occurring on the first day of testing (n=20/197, 10.2%) and the lowest in January 2021 (n=1/202, 0.5%). 2,574 visits for sample self-collection occurred during the study period when independent timing data was collected (April - June 2021). Of those visits, 7.5% (n=193) were timed. The average duration of each visit was 70 seconds. Figure 1. Swab Error Rates Over Time Conclusion Pediatric self-collected lower nasal swabs are a viable and easily tolerated specimen collection method for SARS-CoV-2 surveillance in school settings, as evidenced by the low error rate and short time window of sample self-collection during testing. School administrators should expect errors to drop quickly after implementing testing. Disclosures All Authors: No reported disclosures

14.
Open forum infectious diseases ; 8(Suppl 1):S302-S302, 2021.
Article in English | EuropePMC | ID: covidwho-1563805

ABSTRACT

Background In order to mitigate the spread of SARS-CoV-2 and the COVID-19 pandemic, public health officials have recommended self-isolation, self-quarantine of exposed household contacts (HHC), and mask use to limit viral spread within households and communities. While household transmission of SARS-CoV-2 is common, risk factors for HHC transmission are poorly understood. Methods In this prospective cohort study, we enrolled 37 households with at least one reverse transcription polymerase chain reaction-confirmed (RT-PCR) COVID-19 index case from March 2020 - March 2021, in order to calculate secondary attack rates (SAR) and define risk factors for secondary infections. Participants were tested daily for SARS-CoV-2 via RT-PCR, using self-collected lower nasal samples. Households were followed until all members tested negative for seven consecutive days. We collected demographics, medical conditions, relationship to index case, and socioeconomic indicators. Subgroup data analysis was conducted and stratified by positivity status. Results Of 99 enrolled participants, 37 were index cases and 62 were household contacts (HHC), of whom 25 HHC were infected (40.3%). Secondary attack rate (SAR) was highest among adults caring for a parent (n=4/4, 100%) and parents of index cases (5/10, 50%). Households whose income came from service work had greater risk of transmission compared to households whose primary income was technology (n=5/7;71.4% vs 3/8;37.5% respectively). Pediatric contacts were at lower risk of infection when compared to adult contacts (n=5/18, 27.8% vs n=20/44, 45.5% respectively). Conclusion This study suggests that household transmission represents a key source of community-based infection of SARS-CoV-2. Allocating resources for education/training regarding prevention among infected individuals and their close contacts will be critical for control of future outbreaks of SARS-CoV-2. Disclosures All Authors: No reported disclosures

16.
American Control Conference (ACC) ; : 1547-1552, 2021.
Article in English | Web of Science | ID: covidwho-1485897

ABSTRACT

We develop an online convex optimization method for predicting time series based on streaming observations. We first approximate the evolution of time-varying autoregressive integrated moving average (ARIMA) processes and then propose a discounted online Newton method for estimating time-varying ARIMA time series. Under practical assumptions, we establish dynamic regret bounds that quantify the tracking performance of our algorithm. To verify the effectiveness and robustness of our method, we conduct experiments on prediction problems based on both artificial data and real-world COVID-19 data. To the best of our knowledge, we are the first to report a COVID-19 prediction that utilizes online learning.

17.
Sensors and Materials ; 33(9):3187-3200, 2021.
Article in English | Scopus | ID: covidwho-1471240

ABSTRACT

medical service robot, human-robot interaction, COVID-19, sensor fusion The cabin hospitals used for COVID-19 victims have an infectious environment and thus require highly autonomous systems to provide various services. This article presents a multirobot architecture designed for cabin hospitals with special focus on the sensors used by service robots. The robots' functions include autonomous disinfection, delivery, cleaning, temperature measurement, physical interaction, and conversation assistance. The robots collaborate with each other by using multiple sensors in large and complicated scenes and evolve together. The robots are controlled by cloud controllers considering a human-centered multi-robot collaboration mechanism. This article presents the details of these robots, including the hardware and software architecture of the robots with sensors, the communication modules, and the cloudbased central controllers. It also presents several applications of the robots and discusses open problems. © 2021 M Y U Scientific Publishing Division. All rights reserved.

18.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(8): 1353-1359, 2021 Aug 10.
Article in Chinese | MEDLINE | ID: covidwho-1468522

ABSTRACT

Objective: To establish an index system of population based SARS-CoV-2 nucleic acid screening, and provide reference to determine the screening coverage appropriately. Methods: The literature review and brain storming sessions were used to develop the basic frame and index system of population based SARS-CoV-2 nucleic acid screening. Based on Delphi method and Analytic Hierarchy Process, 21 domestic experts were selected for two rounds of consultation to determine the index system of population based SARS-CoV-2 nucleic acid screening and its weight. Results: The positive indexes of experts in two rounds of consultations were both 100%. The experts' authority coefficients (Cr) were 0.88±0.08 and 0.89±0.07, respectively. And the range of coefficient of variation (CV) were (0.08, 0.24), (0.09, 0.25). The Kendall's W coordination coefficients were 0.34 and 0.22 respectively, which were statistically significant. The index system of population based SARS-CoV-2 nucleic acid screening was established, which had 4 first-level indexes, 11 second-level indexes and 58 third-level indexes. Besides, the weight of each index was determined. Conclusion: The index system of population based SARS-CoV-2 nucleic acid screening has been established, which can provide scientific reference for the health administration to determine the coverage of population based SARS-CoV-2 nucleic acid screening when local COVID-19 epidemic occurs.


Subject(s)
COVID-19 , Nucleic Acids , Humans , Mass Screening , SARS-CoV-2
19.
33rd International Conference on Software Engineering and Knowledge Engineering, SEKE 2021 ; 2021-July:399-404, 2021.
Article in English | Scopus | ID: covidwho-1404147

ABSTRACT

The outbreak of the COVID-19 pandemic arises enormous attention to online education then knowledge tracking is an increasingly crucial task with its vigorous development. However, the surge of student historical interactions and the lack of prior knowledge is engendering a sequence of issues, such as the decrease in prediction accuracy while the increase in training time. Simultaneously, most existing approaches fail to provide in-depth insights into why a student is likely to answer the question incorrectly and what affects the knowledge state of the student. To address those issues, we propose a multi-head self-attention model named MAKT for dynamic knowledge tracing, which makes the prediction results interpretable at the model and instance level. The customized multi-head self-attention layer has high training efficiency owing to its parallelization capability and spends about 6 seconds in each epoch on a single GPU. We further visualize the attention weights of MAKT and student knowledge acquisition tracking, finding that not all historical interactions are equally important but the recent interactions profoundly establish the knowledge state of students. In the end, extensive experiments on three datasets demonstrate the robustness and superiorities of MAKT, improving ACC by 1.14 % and AUC by 1.20 % on average. © 2021 Knowledge Systems Institute Graduate School. All rights reserved.

20.
Chinese Traditional and Herbal Drugs ; 52(7):2178-2183, 2021.
Article in Chinese | Scopus | ID: covidwho-1190614

ABSTRACT

Traditional Chinese medicine injection, a scientific and technological innovation of traditional Chinese medicine, plays a unique advantage in the treatment of severe patients with new corona virus pneumonia (COVID-19). Epidemiological studies have found that a considerable number of severe patients with COVID-19 have cardiovascular diseases such as hypertension and coronary heart disease, which need to be controlled during anti-virus treatment, resulting in the increasingly prevalence of drug interactions between traditional Chinese medicine injections and chemical medicines. By consulting the literatures, we summarized the effects of eight commonly used traditional Chinese medicine injections in Diagnosis and Treatment Protocol for COVID-19 (Trial Version 8) on cytochrome P450 enzyme (CYP450), and analyzed their interaction with commonly used chemical medicines for cardiovascular diseases, so as to provide references for clinical rational administration and promote the advantages of traditional Chinese medicine against the epidemic disease. © 2021, Editorial Office of Chinese Traditional and Herbal Drugs. All right reserved.

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