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1.
Talanta ; 252, 2023.
Article in English | Web of Science | ID: covidwho-2069714

ABSTRACT

Since the last century, animal viruses have posed great threats to the health of humans and the farming industry. Therefore, virus control is of great urgency, and regular, timely, and accurate detection is essential to it. Here, we designed a rapid on-site visual data-sharing detection method for the Newcastle disease virus with smartphone recognition-based immune microparticles. The detection method we developed includes three major modules: preparation of virus detection vectors, sample detection, and smartphone image analysis with data upload. First, the hydrogel microparticles containing active carboxyl were manufactured, which coated nucleocapsid protein of NDV. Then, HRP enzyme-labeled anti-NP nanobody was used to compete with the NDV antibody in the serum for color reaction. Then the rough detection results were visible to the human eyes according to the different shades of color of the hydrogel microparticles. Next, the smartphone application was used to analyze the image to determine the accurate detection results according to the gray value of the hydrogel microparticles. Meanwhile, the result was automatically uploaded to the homemade cloud system. The total detection time was less than 50 min, even without trained personnel, which is shorter than conventional detection methods. According to experimental results, this detection method has high sensitivity and accuracy. And especially, it uploads the detection information via a cloud platform to realize data sharing, which plays an early warning function. We anticipate that this rapid on-site visual data-sharing detection method can promote the development of virus selfchecking at home.

2.
Mmwr-Morbidity and Mortality Weekly Report ; 71(36):1151-1154, 2022.
Article in English | Web of Science | ID: covidwho-2068408

ABSTRACT

What is already known about this topic? Before emergence of the SARS-CoV-2 B.1.1.529 (Omicron) variant, infectious SARS-CoV-2 was unlikely to be cultured at high cycle threshold (Ct) values. Based on this, low Ct values, which are suggestive of high RNA levels, are sometimes used as surrogate markers for infectiousness. What is added by this report? In a longitudinal study including daily nasal swabbing, although Omicron BA.1 sublineage infections exhibited higher Ct values than did pre-Omicron infections, culturable Omicron virus was still detected. Among virus-positive specimens, Ct values were higher for Omicron than for pre-Omicron specimens, especially during the first week of illness. What are the implications for public health practice? Supporting CDC guidance, these data show that Ct values likely do not provide a consistent proxy for infectiousness across SARS-CoV-2 variants.

3.
Frontiers in Environmental Science ; 10, 2022.
Article in English | Scopus | ID: covidwho-2055008

ABSTRACT

The COVID-19 pandemic is dangerous to people’s lives and livelihoods, creating immediate obstacles for organizations that support impacted populations. This research concentrates on the consequences for local microfinance institutions in Pakistan, which is a well-developed sector that has pulled many households out of the poverty trap. Microfinance programs in Pakistan provide financial resources to vulnerable and deprived people to engage in income-generating practices on more favorable terms. As a result, this study addressed and assessed the financial dimensions of managing poverty reduction in rural Pakistan through the microfinance segment and its effectiveness on poverty-reduction programs in Pakistan during the COVID-19 pandemic. The primary data were collected through a questionnaire survey to determine the views of the households, beneficiaries, and non-beneficiaries on the outcome and efficacy of poverty-reduction programs during the pandemic to meet the study objectives. The Mann-Whitney U test of the non-parametric method and Cronbach’s alpha of the data reliability test have been applied for the empirical analysis. According to the non-parametric findings, programs, marital status, working women members, and resources such as land, livestock, business assets, shares, and loans have all been affected during the COVID-19 pandemic. Education, wages, gender, size, child dependency, and district variables are significant factors related to poverty, but they fell into second position during COVID-19. These findings suggests that the small loan system must be improved and made efficient during the pandemic. This could be a practical tool to maintain poor people’s current economic and poverty position. Copyright © 2022 Lu, Dai, Ali, Al-Faryan and Iqbal.

4.
Journal of Social Computing ; 3(2):158-170, 2022.
Article in English | Scopus | ID: covidwho-2026289

ABSTRACT

During the SARS-CoV-2 (COIVD-19) outbreak, China repeatedly stressed that the response to the pandemic required action at all levels of government, including the issuance of Pandemic Bonds to help the country return to work and production. However, studies on the effectiveness of Pandemic Bonds during that period are rare. Starting with China's national financial bond market data after COVID-19 in 2020, this paper focuses on the correlation between the Credit Spreads of the relevant bonds and the corresponding bond market rate of return, based on the Copula model. The empirical analysis is also carried out for multiple dimensional groupings such as enterprises, industries, provinces, and bond maturities. The results show that there is a significant positive correlation between the Credit Spreads of Pandemic Bonds and market returns. In addition, the market correlation is higher for Pandemic Bonds issued in Hubei Province, which is at the center of the 2020 pandemic, and the shorter the maturity of the Pandemic Bond issued, the stronger the relationship with market returns. Finally, this paper provides recommendations for financial regulators and policy makers to consider in their decisions on how to build a more resilient financial system under heavy economic, fiscal, and social pressures. © 2020 Tsinghua University Press.

6.
2nd International Conference on Artificial Intelligence and Computer Engineering, ICAICE 2021 ; : 216-220, 2021.
Article in English | Scopus | ID: covidwho-1948770

ABSTRACT

China is the world's largest pork production and consumption country, with the improvement of people's living standards and consumption upgrade, people's demand for fresh pork and other fresh products is stronger. With the outbreak of African Swine Fever and COVID-19 in China in the past two years, cold chain transportation of pork will replace live pigs as the main mode of pork supply chain. As one of the most important branches of machine learning, deep learning has developed rapidly in recent years and attracted extensive attention at home and abroad. In order to improve the real-time detection of pork freshness, this paper experimented with a variety of deep learning frameworks to achieve pork freshness classification. In this paper, pork freshness is divided into 5 levels according to TVB-N content, and the pictures taken are trained by different deep learning networks, including VGG, GoogLeNet and RestNet. After analyzing the training situation of each network, the advantages of different networks are absorbed and a new improved neural network is built to predict pork freshness. The final classification accuracy reached 97%, Indicating that this is a very efficient and accurate pork freshness classification method. © 2021 IEEE.

7.
Chinese Journal of Microbiology and Immunology (China) ; 42(4):245-250, 2022.
Article in Chinese | EMBASE | ID: covidwho-1928717

ABSTRACT

Objective To analyze the genome characteristics and variations in nucleotides and amino acids of SARS-CoV-2 causing an outbreak in Henan Province in November 2021 and perform the traceability analysis.Methods In this study, throat swab specimens from cases in the acute phase were collected and tested for the nucleic acids of SARS-CoV-2 by real-time fluorescent RT-PCR.SARS-CoV-2 nucleic acid-positive samples were subjected to high-throughput genome sequencing and whole-genome alignment analysis.Results The median Ct values of ORF1ab gene and N gene in 70 positive specimens was 26.41 (15.58 to 39.27) and 24.43 (12.04 to 39.74), respectively.Compared with the sequence of Wuhan-Hu(NC_045512) reference strain, 47 to 49 nucleotide mutations sharing 47 nucleotide mutation and 41 amino acid mutations were found in 63 strains of successfully sequenced SARS-CoV-2.Nine nucleotide mutations and 12 amino acid mutations were found in the spike protein.The index case shared 47 mutations with the Russian imported cases in Henan Province on October 14 and the local cases in Jiangxi Province in October.Moreover, their genomes were highly homologous and they all belonged to the Delta variant (AY.122 evolutionary branch).Conclusions Continuous monitoring of imported COVID-19 cases and prolonging the period of quarantine were needed to reduce the risk of local outbreak and epidemic caused by imported COVID-19 cases.Analysis of the genomic characteristics of SARS-CoV-2 and the variations in nucleotides and amino acids was conducive to trace the origin of COVID-19 outbreak quickly and provide reference for precise control.

8.
Zhonghua Gan Zang Bing Za Zhi ; 30(5): 527-533, 2022 May 20.
Article in Chinese | MEDLINE | ID: covidwho-1911771

ABSTRACT

Objective: To retrospectively analyze the characteristics and influencing factors of liver function changes in 111 elderly patients with COVID-19 pneumonia. Methods: 111 elderly patients with COVID-19 admitted to the Department of Infectious Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from February 5 to March 3, 2020 were enrolled. According to the severity of disease and liver function condition, they were divided into severe group (n=40), normal group (n=71), abnormal liver function group (n=86) and normal liver function group (n=25). The indexes related to liver function changes [total bilirubin (TBil), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and γ-glutamyl transferase (GGT)] and related influencing factors were analyzed. Results: Among 111 cases, 86 (77.5%) had abnormal liver function of varying degrees, and 28 (25.2%) had liver injury. The abnormal rates of TBil, AST, ALP and GGT were significantly higher in the severe group than normal group (P<0.05). There were no significant differences in age, ribavirin, glucocorticoid and the application of lopinavir-ritonavir tablets between the abnormal liver function and the normal group (P>0.05). The proportion of male was significantly higher in the abnormal liver function than normal liver function group (P<0.05). Conclusion: Elderly COVID-19 patients have a higher proportion of abnormal liver function, and patients in the severe group are more likely to have higher level of TB, AST, ALP and GGT. The abnormal liver function may be related to the direct viral infection of the liver and the inflammatory immune response of the body after infection in elderly patients.


Subject(s)
COVID-19 , Liver Diseases , Aged , Alkaline Phosphatase , Aspartate Aminotransferases , Bilirubin , Humans , Liver Function Tests , Male , Retrospective Studies , gamma-Glutamyltransferase
9.
PubMed; 2022.
Preprint in English | PubMed | ID: ppcovidwho-338328

ABSTRACT

BACKGROUND: Mechanisms underlying persistent cardiopulmonary symptoms following SARS-CoV-2 infection (post-acute sequelae of COVID-19 "PASC" or "Long COVID") remain unclear. The purpose of this study was to elucidate the pathophysiology of cardiopulmonary PASC using multimodality cardiovascular imaging including cardiopulmonary exercise testing (CPET), cardiac magnetic resonance imaging (CMR) and ambulatory rhythm monitoring. METHODS: We performed CMR, CPET, and ambulatory rhythm monitoring among adults > 1 year after PCR-confirmed SARS-CoV-2 infection in the UCSF Long-Term Impact of Infection with Novel Coronavirus cohort (LIINC;NCT04362150 ) and correlated findings with previously measured biomarkers. We used logistic regression to estimate associations with PASC symptoms (dyspnea, chest pain, palpitations, and fatigue) adjusted for confounders and linear regression to estimate differences between those with and without symptoms adjusted for confounders. RESULTS: Out of 120 participants in the cohort, 46 participants (unselected for symptom status) had at least one advanced cardiac test performed at median 17 months following initial SARS-CoV-2 infection. Median age was 52 (IQR 42-61), 18 (39%) were female, and 6 (13%) were hospitalized for severe acute infection. On CMR (n=39), higher extracellular volume was associated with symptoms, but no evidence of late-gadolinium enhancement or differences in T1 or T2 mapping were demonstrated. We did not find arrhythmias on ambulatory monitoring. In contrast, on CPET (n=39), 13/23 (57%) with cardiopulmonary symptoms or fatigue had reduced exercise capacity (peak VO 2 <85% predicted) compared to 2/16 (13%) without symptoms (p=0.008). The adjusted difference in peak VO 2 was 5.9 ml/kg/min lower (-9.6 to -2.3;p=0.002) or -21% predicted (-35 to -7;p=0.006) among those with symptoms. Chronotropic incompetence was the primary abnormality among 9/15 (60%) with reduced peak VO 2 . Adjusted heart rate reserve <80% was associated with reduced exercise capacity (OR 15.6, 95%CI 1.30-187;p=0.03). Inflammatory markers (hsCRP, IL-6, TNF-alpha) and SARS-CoV-2 antibody levels measured early in PASC were negatively correlated with peak VO 2 more than 1 year later. CONCLUSIONS: Cardiopulmonary symptoms and elevated inflammatory markers present early in PASC are associated with objectively reduced exercise capacity measured on cardiopulmonary exercise testing more than 1 year following COVID-19. Chronotropic incompetence may explain reduced exercise capacity among some individuals with PASC. Clinical Perspective: What is New?Elevated inflammatory markers in early post-acute COVID-19 are associated with reduced exercise capacity more than 1 year later.Impaired chronotropic response to exercise is associated with reduced exercise capacity and cardiopulmonary symptoms more than 1 year after SARS-CoV-2 infection.Findings on ambulatory rhythm monitoring point to perturbed autonomic function, while cardiac MRI findings argue against myocardial dysfunction and myocarditis. Clinical Implications: Cardiopulmonary testing to identify etiologies of persistent symptoms in post-acute sequalae of COVID-19 or "Long COVID" should be performed in a manner that allows for assessment of heart rate response to exercise. Therapeutic trials of anti-inflammatory and exercise strategies in PASC are urgently needed and should include assessment of symptoms and objective testing with cardiopulmonary exercise testing.

10.
Hsi-An Chiao Tung Ta Hsueh/Journal of Xi'an Jiaotong University ; 56(5):43-53, 2022.
Article in Chinese | Scopus | ID: covidwho-1876106

ABSTRACT

To study the spreading mechanism and risk and predict the spreading trend of COVID-19, and provide supports for the government to formulate prevention and control policies, a new nonlinear dynamic model, i.e., the susceptible-low risk-exposed-infectious-removed (SLEIR) model is proposed, and the population with protection measures is regarded as a low-risk group and included into this model. The basic reproduction number, equilibrium, stability and bifurcation are analyzed to reveal the spreading mechanism, and the data on COVID-19 in India is used for least-squares fitting of model parameters and some initial values. The fitted parameters are used to predict the spreading trend in India. Predicting results show that the average relative errors of the epidemic prediction are 4.107% and 2.805% from March to April and from April to May, respectively. For the latest epidemic prediction of India in October, the average relative error is 3.266%. These simulations indicate that the proposed model can accurately predict COVID-19 spreading in India, is more suitable for analyzing its spreading in India with higher prediction accuracy compared with the traditional SEIR model, and can provide technical support for the government of India to select prevention and control measures. © 2022, Editorial Office of Journal of Xi'an Jiaotong University. All right reserved.

11.
Embase; 2021.
Preprint in English | EMBASE | ID: ppcovidwho-334682

ABSTRACT

B-cell epitopes (BCEs) are a set of specific sites on the surface of an antigen that binds to an antibody produced by B-cell. The recognition of BCEs is a major challenge for drug design and vaccines development. Compared with experimental methods, computational approaches have strong potential for BCEs prediction at much lower cost. Moreover, most of the currently methods focus on using local information around target residue without taking the global information of the whole antigen sequence into consideration. We propose a novel deep leaning method through combing local features and global features for BCEs prediction. In our model, two parallel modules are built to extract local and global features from the antigen separately. For local features, we use Graph Convolutional Networks(GCNs) to capture information of spatial neighbors of a target residue. For global features, Attention-Based Bidirectional Long Short-Term Memory(Att-BLSTM) networks are applied to extract information from the whole antigen sequence. Then the local and global features are combined to predict BCEs. The experiments show that the proposed method achieves superior performance over the state-of-the-art BCEs prediction methods on benchmark datasets. Also, we compare the performance differences between data with or without global features. The experimental results show that global features play an important role in BCEs prediction. Our detailed case study on the BCEs prediction for SARS-Cov-2 receptor binding domain confirms that our method is effective for predicting and clustering true BCEs.

12.
Journal of Sexual Medicine ; 19(4):S69, 2022.
Article in English | EMBASE | ID: covidwho-1796414

ABSTRACT

Introduction: High-Intensity Focused Electromagnetic (HIFEM) field technology utilizes rapidly changing magnetic fields that generate electrical currents in the underlying tissue where it depolarizes motor neurons and causes muscle contractions. BTL Emsella provides non-invasive electromagnetic stimulation of pelvic floor musculature for the purpose of rehabilitation of weak pelvic muscles and restoration of neuromuscular control for the treatment of male and female incontinence. Novel protocol U2 is intended for men and uses a field intensity max of 2.5 T and a 10 cm depth of penetration for 28 minutes. Objective: Determine the effects of High-Intensity Focused Electromagnetic (HIFEM) field technology on the intensity and duration of ejaculation in men, with additional observations on erectile function using the IIEF-15 and urination using the IPSS. Methods: We looked at the effects of HIFEM on ejaculation, erectile function, and urination. Our IRB-approved protocol was one 28 minutes pelvic floor treatment per week for 4 weeks. At baseline, end of treatment, and one month post-treatment, the patient completed the IIEF-15, IPSS, and the LuBE Score, a four-question 5 point Likert style questionnaire created specifically for this study to investigate patient-reported aspects of orgasm, including volume, force, duration, and intensity of ejaculation. 0 is no change, 1 is increased, 2 is dramatically increased, -1 is decreased, -2 is dramatically decreased. Men participated with their sexual partners who also received four weekly treatments. Results: 12 men, average age of 57, completed the protocol. The range of the LuBE score is -8 to 8. The LuBE Score increased from baseline 0 up to 2.1 (median is 3 with a range of -1 to 5) to 2.7 (median of 3 with a range of 0 to 4) one month after the completion of treatment. The IIEF-15 increased from 54 at baseline to 60.3 at the completion of treatment and 60.4 one month after the completion of treatment. The IPSS declined from 7.1 to 4.6 at the completion of treatment and down to 3.3 one month after th Conclusions: We conclude that the U2 protocol for HIFEM boosts the strength of the bulbocavernosus and ischiocavernosus muscle and the pelvic floor resulting in an increase in volume, force, duration and intensity of ejaculation. In addition, there was a six-point increase in IIEF-15 score. There was a 3 to 4 point drop in IPSS score. We were surprised to see improvements in IIEF-15 and IPSS, and this should be investigated further. COVID limited patient recruitment, but the results indicate that pelvic HIFEM potentially improves ejaculation. Based on patient communications, I believe that more treatments than the four provided will add to the benefits. I plan on studies with more participants and extended treatment sessions. Disclosure: Yes, this is sponsored by industry/sponsor: BTL Clarification: No industry support in study design or execution Any of the authors act as a consultant, employee or shareholder of an industry for: AFFIRM Science

13.
Kontakt ; 24(1):48-54, 2022.
Article in English | Scopus | ID: covidwho-1786606

ABSTRACT

Purpose: COVID-19 has caused a shift toward consumer-facing technology such as mobile health (mHealth) applications. However, most mHealth apps do not use accessible language. Standardized terminologies have potential to solve this problem but have not been simplified for consumer use. Methods: We used a standardized health terminology, the Omaha System, as the framework to develop the Simplified Omaha System Terms (SOST) for use within a mHealth application, MyStrengths + MyHealth. Plain language principles informed the SOST development in three phases, a community-validation focus group enabled feedback from diverse end-users, a readability assessment provide validation to the desired goal readability level. Results: The community-validation members (n = 19) ages ranged from 22 to 74;51% male, 84% people of color, and 21% college educated. The reading level of the final SOST averaged 3.86 on the Coleman–Liau Index (fourth grade). A case study showed meaningful whole-person health data were generated in a community-led study during COVID-19. Conclusions: Community validation and readability assessment demonstrated accessible language for a clinical terminology. The SOST was deployed successfully in MyStrengths + My Health and in a community-led study. The Omaha System as a framework for the SOST may enable the data to be integrated with clinical datasets. Future research should focus on validation of SOST in additional languages and integration within electronic health platforms. © 2022 The Authors.

14.
Future of Information and Communication Conference, FICC 2022 ; 439 LNNS:714-721, 2022.
Article in English | Scopus | ID: covidwho-1772869

ABSTRACT

The COVID-19 pandemic altered the way millions of citizens around the world live and work, establishing a so-called new norm in social standards. Also, the pandemic has created a variety of unique circumstances that affect society and business due to cybercrime. Because of the increased anxiety caused by the pandemic, people were more likely to launch successful cyberattacks and this increased the variety and number of cyberattacks. We present a two-dimensional classification of existing research on Hybrid Cryptography Models based on processing phases and applications domain. As a result, we were able comparison study has been made between other state-of-the-art existed ones to aid hybrid models’ performance enhancement in the aftermath of this pandemic. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

15.
Journal of Virology ; 96(3):14, 2022.
Article in English | Web of Science | ID: covidwho-1755770

ABSTRACT

Human adenovirus serotype 26 (Ad26) is used as a gene-based vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and HIV-1. However, its primary receptor portfolio remains controversial, potentially including sialic acid, coxsackie and adenovirus receptor (CAR), integrins, and CD46. We and others have shown that Ad26 can use CD46, but these observations were questioned on the basis of the inability to cocrystallize Ad26 fiber with CD46. Recent work demonstrated that Ad26 binds CD46 with its hexon protein rather than its fiber. We examined the functional consequences of Ad26 for infection in vitro and in vivo. Ectopic expression of human CD46 on Chinese hamster ovary cells increased Ad26 infection significantly. Deletion of the complement control protein domain CCP1 or CCP2 or the serine-threonine-proline (STP) region of CD46 reduced infection. Comparing wild-type and sialic acid-deficient CHO cells, we show that the usage of CD46 is independent of its sialylation status. Ad26 transduction was increased in CD46 transgenic mice after intramuscular (i.m.) injection but not after intranasal (i.n.) administration. Ad26 transduction was 10-fold lower than Ad5 transduction after intratumoral (i.t.) injection of CD46expressing tumors. Ad26 transduction of liver was 1,000-fold lower than that ofAd5 after intravenous (i.v.) injection. These data demonstrate the use of CD46 by Ad26 in certain situations but also show that the receptor has little consequence by other routes of administration. Finally, i.v. injection of high doses of Ad26 into CD46 mice induced release of liver enzymes into the bloodstream and reduced white blood cell counts but did not induce thrombocytopenia. This suggests that Ad26 virions do not induce direct clotting side effects seen during coronavirus disease 2019 (COVID-19) vaccination with this serotype of adenovirus. IMPORTANCE The human species D Ad26 is being investigated as a low-seroprevalence vector for oncolytic virotherapy and gene-based vaccination against HIV-1 and SARS-CoV-2. However, there is debate in the literature about its tropism and receptor utilization, which directly influence its efficiency for certain applications. This work was aimed at determining which receptor(s) this virus uses for infection and its role in virus biology, vaccine efficacy, and, importantly, vaccine safety.

16.
Open Forum Infectious Diseases ; 8(SUPPL 1):S89-S91, 2021.
Article in English | EMBASE | ID: covidwho-1746775

ABSTRACT

Background. SARS-CoV-2 variants of concern (VOC) have challenged real-time reverse transcriptase polymerase chain reaction (RT-PCR) methods for the diagnosis of COVID-19. Methods. The CDC 2019-Novel Coronavirus real-time RT-PCR panel was modified to create a single-plex extraction-free proxy RT-PCR assay, VOCFast™. This assay uses the nucleocapsid N1 as well as novel primer/probe pairs to target VOC mutations in the Orf1a and spike (S) genes. For analytical validation of VOCFast, synthetic controls for the Wuhan, alpha/B.1.1.7, beta/B.1.351, and gamma/P.1 strains were tested at various concentrations. Clinical validation was performed using patient anterior nares swab and saliva specimens collected in the Denver, CO area between Nov 2020 and Feb 2021 or in March 2021. Orthogonal next-generation sequencing (NGS) was also performed. Results. Similar N1 quantification cycle (Cq) values corresponding to viral load were observed for all strains, suggesting that VOC mutations do not affect performance of the N1 primer/probe. Orf1a-mut and S1-mut primer/probes generated a stable high Cq value for the Wuhan strain. Conversely, Orf1a-mut Cq values were inversely correlated with viral load for all VOC. The S1-mut Cq was inversely correlated with viral load of the alpha strain, but did not reliably amplify beta/gamma VOC. The limit of detection was 8 copies/uL. The first set of COVID-19 patient specimens revealed no amplification using Orf1amut whereas 53% of specimens collected in Mar 2021 demonstrated amplification by Orf-1a. Orthogonal testing by the SARS-CoV-2 NGS Assay and COVID-DX software demonstrated that 12/12 alpha strains, 2/2 beta/gamma strains, and 33/33 Wuhan strains were correctly identified by VOCFast. Conclusion. The combination of the N1, Orf1a-mut, and S1-mut primers/probes in VOCFast can distinguish the Wuhan, alpha, and beta/gamma strains and it consistent with NGS results. Testing of clinical samples revealed that VOC emerged in Denver, CO in March 2021. Future work to discriminate beta, gamma, and emerging VOC is ongoing. In summary, VOCFast is an extraction-free RT-PCR assay for nasal swab and saliva specimens that can identify VOC with a turnaround time suitable for clinical testing.

17.
Embase; 2021.
Preprint in English | EMBASE | ID: ppcovidwho-330558

ABSTRACT

We evaluate the impact of government-mandated proof of vaccination requirements for access to public venues and non-essential businesses on COVID-19 vaccine uptake. We find that the announcement of a mandate is associated with a rapid and significant surge in new vaccinations (more than 60% increase in weekly first doses), using the variation in the timing of these measures across Canadian provinces in a difference-in-differences approach. Time-series analysis for each province and for France, Italy and Germany corroborates this finding. Counterfactual simulations using our estimates suggest the following cumulative gains in the vaccination rate among the eligible population (age 12 and over) as of October 31, 2021: up to 5 percentage points (p.p.) (90% CI 3.9-5.8) for Canadian provinces, adding up to 979,000 (425,000-1,266,000) first doses in total for Canada (5 to 13 weeks after the provincial mandate announcements), 8 p.p. (4.3-11) for France (16 weeks post-announcement), 12 p.p. (5-15) for Italy (14 weeks post-announcement) and 4.7 p.p. (4.1-5.1) for Germany (11 weeks post-announcement).

18.
PubMed; 2021.
Preprint in English | PubMed | ID: ppcovidwho-330088

ABSTRACT

Several fast-spreading variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have become the dominant circulating strains that continue to fuel the COVID-19 pandemic despite intensive vaccination efforts throughout the world. We report here cryo-EM structures of the full-length spike (S) trimers of the B.1.1.7 and B.1.351 variants, as well as their biochemical and antigenic properties. Mutations in the B.1.1.7 protein increase the accessibility of its receptor binding domain and also the binding affinity for receptor angiotensin-converting enzyme 2 (ACE2). The enhanced receptor engagement can account for the increased transmissibility and risk of mortality as the variant may begin to infect efficiently infect additional cell types expressing low levels of ACE2. The B.1.351 variant has evolved to reshape antigenic surfaces of the major neutralizing sites on the S protein, rendering complete resistance to some potent neutralizing antibodies. These findings provide structural details on how the wide spread of SARS-CoV-2 enables rapid evolution to enhance viral fitness and immune evasion. They may guide intervention strategies to control the pandemic.

19.
2020 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2020 ; 2020.
Article in English | Scopus | ID: covidwho-1706502

ABSTRACT

Computed tomography (CT) of COVID-19 manifests a relatively global effect through the whole lungs, like peripheral ground glass, consolidation, reticular pattern, nodules etc. This characteristic effect renders the difficulties in differentiating COVID-19 from the normal body or other lung diseases by CT. This work presents a novel method to relieve the difficulties by reducing the global effect through the 3D whole lung volume into 2D-like domain. The hypothesis is that the lung tissue shares the similar anatomic structure within a small lung sub-volume for normal subjects. Therefore, the anatomic land-markers along the z-axis, denoted as Lung Marks are used to eliminate axial variable. Our experiments indicated that 30 Lung Marks are sufficient to eliminate the axial variable. The method computes texture measures from each 2D-like volumetric data and maps the measures on to the corresponding Lung Mark, resulting in a profile along the z-axis. The difference of the profiles between two different abnormalities is the proposed sensitive merit to differentiate COVID-19 cases from others in CT images. 48 COVID-19 cases and 48 normal screening cases were used to test the effectiveness of the proposed sensitive merit. Intensity and gradient based texture descriptors were computed from each axial cross image at the corresponding Lung Mark along the z-axis. Euclidean, Jaccard and Dice distances are calculated to generate the profiles of the proposed sensitive merit. Consistent results are observed across texture descriptor types and distance types in the texture measure between the normal and COVID-19 subjects. Uneven Profiles demonstrate the variation along the z-axis. With Lung Mark, the variation of texture descriptor has been reduced prominently. The Gradient based descriptor is more sensitive. Individual Haralick features analysis shows the 2nd and 10th dimensions are most distinguishable. © 2020 IEEE

20.
IEEE Internet Computing ; 26(1):60-67, 2022.
Article in English | Scopus | ID: covidwho-1704110

ABSTRACT

The motivation of this work is to build a multimodal-based COVID-19 pandemic forecasting platform for a large-scale academic institution to minimize the impact of COVID-19 after resuming academic activities. The design of this multimodality work is steered by video, audio, and tweets. Before conducting COVID-19 prediction, we first trained diverse models, including traditional machine learning models (e.g., Naive Bayes, support vector machine, and TF-IDF) and deep learning models [e.g., long short-term memory (LSTM), MobileNetV2, and SSD], to extract meaningful information from video, audio, and tweets by 1) detecting and counting face masks, 2) detecting and counting cough for potential infected cases, and 3) conducting sentiment analysis based on COVID-19-related tweets. Finally, we fed the multimodal analysis results together with daily confirmed cases data and social distancing metrics into the LSTM model to predict the daily increase rate of confirmed cases for the next week. Important observations with supporting evidence are presented. © 1997-2012 IEEE.

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