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1.
Journal of Operations Management ; 69(3):384-403, 2023.
Article in English | ProQuest Central | ID: covidwho-2298799

ABSTRACT

This study explores how firms sought to effectively match their internal competence with external resources from the supply chain network to improve operational resilience (OR) during the COVID‐19 pandemic. Drawing upon matching theory, this study provides an internal–external matching perspective based on flexibility–stability features of OR to explain the operational mechanisms underlying the different matchings between internal flexibility (i.e., product diversity)/stability (i.e., operational efficiency) and external flexibility (i.e., structural holes)/stability (i.e., network centrality). We find that more heterogeneous matchings between internal (external) flexibility and external (internal) stability have a complementary effect that enhances OR, whereas more homogeneous matchings between internal flexibility (or stability) and external flexibility (or stability) have a substitutive effect that reduces OR. This study provides valuable contributions to research focusing on the supply chain, organizational resilience, and operations management.

2.
Chinese Journal of Zoonoses ; 38(9):771-777, 2022.
Article in Chinese | GIM | ID: covidwho-2298711

ABSTRACT

Whole-genome sequencing of upper respiratory tract specimens from patients with confirmed COVID-19 in Henan Province was performed to compare the performance of the Illumina and Oxford Nanopore sequencing platforms, thus providing a reference for whole-genome monitoring of the novel coronavirus (SARS-CoV-2). Ten samples from COVID-19 cases in Henan Province from June 2021 to January 2022 were collected and sequenced with Illumina and Nanopore high-through-put sequencing technology to obtain full genome sequences of the novel coronavirus, which were compared with the Wuhan reference sequence (Wuhan-Hu-1). Bioinformatics software (CLC) was used for sequence alignment analysis. Three of the ten samples were Omicron (BA.1) variants with 55,61 nucleotide variation sites. One sample was an Alpha (B.1.1.7) variant with 41 nucleotide variation sites. Six samples were Delta (8.1.617.2) variants with 35,42,47 nucleotide variation sites. The sequence identity of mutation sites in six samples was 100%, and the mutation sites in the S genome segment of seven samples were consistent. For samples with a Ct value < 33, both next-generation and third-generation sequencing achieved high genome coverage and sequencing depth. A significant difference in coverage was observed between second-generation sequencing and third-generation sequencing (t=-2.037, P < 0.06). However, the coverage at different time points of the third-generation sequencing did not significantly differ (F=2.498, P > 0.05). The needs for SARS-CoV-2 mutant detection could be met through use of either high-throughput sequencing platform. The identification of mutations in the novel coronavirus through Illumina high-throughput sequencing was more accurate, whereas Nanopore high-throughput sequencing technology could be used for rapid detection and typing of different novel coronaviruses.

4.
BMJ Open ; 12(11): e063919, 2022 11 11.
Article in English | MEDLINE | ID: covidwho-2119454

ABSTRACT

ObjectiveTwo COVID-19 outbreaks occurred in Henan province in early 2022-one was a Delta variant outbreak and the other was an Omicron variant outbreak. COVID-19 vaccines used at the time of the outbreak were inactivated, 91.8%; protein subunit, 7.5%; and adenovirus5-vectored, 0.7% vaccines. The outbreaks provided an opportunity to evaluate variant-specific breakthrough infection rates and relative protective effectiveness of homologous inactivated COVID-19 vaccine booster doses against symptomatic infection and pneumonia. DESIGN: Retrospective cohort study METHODS: We evaluated relative vaccine effectiveness (rVE) with a retrospective cohort study of close contacts of infected individuals using a time-dependent Cox regression model. Demographic and epidemiologic data were obtained from the local Centers for Disease Control and Prevention; clinical and laboratory data were obtained from COVID-19-designated hospitals. Vaccination histories were obtained from the national COVID-19 vaccination dataset. All data were linked by national identification number. RESULTS: Among 784 SARS-CoV-2 infections, 379 (48.3%) were caused by Delta and 405 (51.7%) were caused by Omicron, with breakthrough rates of 9.9% and 17.8%, respectively. Breakthrough rates among boosted individuals were 8.1% and 4.9%. Compared with subjects who received primary vaccination series ≥180 days before infection, Cox regression modelling showed that homologous inactivated booster vaccination was statistically significantly associated with protection from symptomatic infection caused by Omicron (rVE 59%; 95% CI 13% to 80%) and pneumonia caused by Delta (rVE 62%; 95% CI 34% to 77%) and Omicron (rVE 87%; 95% CI 3% to 98%). CONCLUSIONS: COVID-19 vaccination in China provided good protection against symptomatic COVID-19 and COVID-19 pneumonia caused by Delta and Omicron variants. Protection declined 6 months after primary series vaccination but was restored by homologous inactivated booster doses given 6 months after the primary series.


Subject(s)
COVID-19 , United States , Humans , Vaccines, Inactivated , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , Retrospective Studies , Vaccine Efficacy , SARS-CoV-2
5.
Emerg Microbes Infect ; 11(1): 1950-1958, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1937611

ABSTRACT

Using a three-prefecture, two-variant COVID-19 outbreak in Henan province in January 2022, we evaluated the associations of primary and booster immunization with China-produced COVID-19 vaccines and COVID-19 pneumonia and SARS-CoV-2 viral load among persons infected by Delta or Omicron variant. We obtained demographic, clinical, vaccination, and multiple Ct values of infections ≥3 years of age. Vaccination status was either primary series ≥180 days prior to infection; primary series <180 days prior to infection, or booster dose recipient. We used logistic regression to determine odds ratios (OR) of Delta and Omicron COVID-19 pneumonia by vaccination status. We analysed minimum Ct values by vaccination status, age, and variant. Of 826 eligible cases, 405 were Delta and 421 were Omicron cases; 48.9% of Delta and 19.0% of Omicron cases had COVID-19 pneumonia. Compared with full primary vaccination ≥180 days before infection, the aOR of pneumonia was 0.48 among those completing primary vaccination <180 days and 0.18 among booster recipients among these Delta infections. Among Omicron infections, the corresponding aOR was 0.34 among those completing primary vaccination <180 days. There were too few (ten) Omicron cases among booster dose recipients to calculate a reliable OR. There were no differences in minimum Ct values by vaccination status among the 356 Delta cases or 70 Omicron cases. COVID-19 pneumonia was less common among Omicron cases than Delta cases. Full primary vaccination reduced pneumonia effectively for 6 months; boosting six months after primary vaccination resulted in further reduction. We recommend accelerating the pace of booster dose administration.


Subject(s)
COVID-19 , Pneumonia , COVID-19/prevention & control , COVID-19 Vaccines , China/epidemiology , Humans , Immunization, Secondary/methods , SARS-CoV-2 , Viral Load
6.
Nat Commun ; 13(1): 2766, 2022 05 19.
Article in English | MEDLINE | ID: covidwho-1927082

ABSTRACT

A major challenge in coronavirus vaccination and treatment is to counteract rapid viral evolution and mutations. Here we demonstrate that CRISPR-Cas13d offers a broad-spectrum antiviral (BSA) to inhibit many SARS-CoV-2 variants and diverse human coronavirus strains with >99% reduction of the viral titer. We show that Cas13d-mediated coronavirus inhibition is dependent on the crRNA cellular spatial colocalization with Cas13d and target viral RNA. Cas13d can significantly enhance the therapeutic effects of diverse small molecule drugs against coronaviruses for prophylaxis or treatment purposes, and the best combination reduced viral titer by over four orders of magnitude. Using lipid nanoparticle-mediated RNA delivery, we demonstrate that the Cas13d system can effectively treat infection from multiple variants of coronavirus, including Omicron SARS-CoV-2, in human primary airway epithelium air-liquid interface (ALI) cultures. Our study establishes CRISPR-Cas13 as a BSA which is highly complementary to existing vaccination and antiviral treatment strategies.


Subject(s)
COVID-19 Drug Treatment , SARS-CoV-2 , Antiviral Agents/pharmacology , Humans , Liposomes , Nanoparticles , SARS-CoV-2/genetics
7.
arxiv; 2022.
Preprint in English | PREPRINT-ARXIV | ID: ppzbmed-2202.12264v1

ABSTRACT

The constrained outbreak of COVID-19 in Mainland China has recently been regarded as a successful example of fighting this highly contagious virus. Both the short period (in about three months) of transmission and the sub-exponential increase of confirmed cases in Mainland China have proved that the Chinese authorities took effective epidemic prevention measures, such as case isolation, travel restrictions, closing recreational venues, and banning public gatherings. These measures can, of course, effectively control the spread of the COVID-19 pandemic. Meanwhile, they may dramatically change the human mobility patterns, such as the daily transportation-related behaviors of the public. To better understand the impact of COVID-19 on transportation-related behaviors and to provide more targeted anti-epidemic measures, we use the huge amount of human mobility data collected from Baidu Maps, a widely-used Web mapping service in China, to look into the detail reaction of the people there during the pandemic. To be specific, we conduct data-driven analysis on transportation-related behaviors during the pandemic from the perspectives of 1) means of transportation, 2) type of visited venues, 3) check-in time of venues, 4) preference on "origin-destination" distance, and 5) "origin-transportation-destination" patterns. For each topic, we also give our specific insights and policy-making suggestions. Given that the COVID-19 pandemic is still spreading in more than 200 countries and territories worldwide, infecting millions of people, the insights and suggestions provided here may help fight COVID-19.


Subject(s)
COVID-19
8.
Cell Rep Methods ; 2(2): 100170, 2022 Feb 28.
Article in English | MEDLINE | ID: covidwho-1664828

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the third human coronavirus within 20 years that gave rise to a life-threatening disease and the first to reach pandemic spread. To make therapeutic headway against current and future coronaviruses, the biology of coronavirus RNA during infection must be precisely understood. Here, we present a robust and generalizable framework combining high-throughput confocal and super-resolution microscopy imaging to study coronavirus infection at the nanoscale. Using the model human coronavirus HCoV-229E, we specifically labeled coronavirus genomic RNA (gRNA) and double-stranded RNA (dsRNA) via multi-color RNA immunoFISH and visualized their localization patterns within the cell. The 10-nm resolution achieved by our approach uncovers a striking spatial organization of gRNA and dsRNA into three distinct structures and enables quantitative characterization of the status of the infection after antiviral drug treatment. Our approach provides a comprehensive imaging framework that will enable future investigations of coronavirus fundamental biology and therapeutic effects.

9.
China CDC Wkly ; 4(4): 57-65, 2022 Jan 28.
Article in English | MEDLINE | ID: covidwho-1631490

ABSTRACT

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Effectiveness of China's 2 inactivated vaccines (BBIBP-CorV and CoronaVac) against pre-Delta severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants ranged from 47% to over 90%, depending on the clinical endpoint, and with greater effectiveness against more severe coronavirus disease 2019 (COVID-19). During an outbreak in Guangdong, inactivated vaccine effectiveness (VE) against the Delta variant was 70% for symptomatic infection and 100% for severe COVID-19. However, separate or combined VE estimates for the two inactivated vaccines against Delta are not available. WHAT IS ADDED BY THIS REPORT?: In an outbreak that started in a hospital, VEs of completed primary vaccination with inactivated COVID-19 vaccines against symptomatic COVID-19, COVID-19 pneumonia, and severe COVID-19 caused by the Delta variant were 51%, 61%, and 82%. Completed primary vaccination reduced the risk of progressing from mild to moderate or severe COVID-19 by 74%. VE estimates for BBIBP-CorV and CoronaVac or combined vaccination were similar, and partial vaccination was ineffective. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: Completed primary vaccination with either of the 2 inactivated COVID-19 vaccines reduces risk of symptomatic COVID-19, COVID-19 pneumonia, and severe COVID-19 caused by the Delta variant. Completion of the completed primary vaccination with two doses is necessary for protection from Delta.

11.
Curr Opin Pharmacol ; 54: 166-172, 2020 10.
Article in English | MEDLINE | ID: covidwho-943015

ABSTRACT

HIV-1 reverse transcriptase inhibitors (RTIs) are indispensable components of highly active antiretroviral therapy (HAART), which has achieved great success in controlling AIDS epidemic in reducing drastically the morbidity and mortality of HIV-infected patients. RTIs are divided into two categories, nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs). In this review, the recent discoveries in NRTIs and NNRTIs, including approved anti-HIV drugs and noteworthy drug candidates in different development stages, are summarized, and their future direction is prospected.


Subject(s)
HIV Infections/drug therapy , HIV-1 , Reverse Transcriptase Inhibitors/therapeutic use , Humans
12.
Clin Chim Acta ; 511: 346-351, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-907115

ABSTRACT

The global coronavirus disease 2019 (COVID-19) pandemic has posed great challenges in people's daily lives. Highly sensitive laboratory techniques played a critical role in clinical COVID-19 diagnosis and management. In this study the feasibility of using a new digital PCR-based detection assay for clinical COVID-19 diagnosis was investigated by comparing its performance with that of RT-PCR. Clinical patient samples and samples obtained from potentially contaminated environments were analyzed. The study included 10 patients with confirmed COVID-19 diagnoses, 32 validated samples of various types derived from different clinical timepoints and sites, and 148 environmentally derived samples. SARS-CoV-2 nucleic acids were more readily detected in respiratory tract samples (35.0%). In analyses of environmentally derived samples, the positivity rate of air samples was higher than that of surface samples, probably due to differences in virus concentrations. Digital PCR detected SARS-CoV-2 in several samples that had previously been deemed negative, including 3 patient-derived samples and 5 environmentally derived samples. In this study digital PCR exhibited higher sensitivity than conventional RT-PCR, suggesting that it may be a useful new method for clinical SARS-CoV-2 detection. Improvement of SARS-CoV-2 detection would substantially reduce the rates of false-negative COVID-19 test results, in particular those pertaining to asymptomatic carriers.


Subject(s)
COVID-19/diagnostic imaging , COVID-19/genetics , Digital Technology/standards , Real-Time Polymerase Chain Reaction/standards , SARS-CoV-2/genetics , Adult , Aged , Aged, 80 and over , Digital Technology/trends , Female , Humans , Male , Middle Aged , Real-Time Polymerase Chain Reaction/trends , Reproducibility of Results , SARS-CoV-2/isolation & purification
13.
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery ; (12): 359-363, 2020.
Article in Chinese | WPRIM (Western Pacific), WPRIM (Western Pacific) | ID: covidwho-860953

ABSTRACT

@#Since December 2019, a novel coronavirus (2019-nCoV, SARS-CoV-2) pneumonia (COVID-19) outbreak has occurred in Wuhan, Hubei Province, and the epidemic situation has continued to spread. Such cases have also been found in other parts of the country. The spread of the novel coronavirus pneumonia epidemic has brought great challenges to the clinical practice of thoracic surgery. Outpatient clinics need to strengthen the differential diagnosis of ground glass opacity and pulmonary plaque shadows. During the epidemic, surgical indications are strictly controlled, and selective surgery is postponed. Patients planning to undergo a limited period of surgery should be quarantined for 2 weeks and have a nucleic acid test when necessary before surgery. For patients who are planning to undergo emergency surgery, nucleic acid testing should be carried out before surgery, and three-level protection should be performed during surgery. Patients who are planning to undergo emergency surgery in the epidemic area should be confirmed with or without novel coronavirus pneumonia before operation, and perform nucleic acid test if necessary. Surgical disinfection and isolation measures should be strictly carried out. Among postoperative patients, cases with new coronavirus infection were actively investigated. For the rescue of patients with novel coronavirus infection, attention needs to be paid to prevention and treatment and related complications, including mechanical ventilation-related pneumothorax or mediastinal emphysema, and injury after tracheal intubation.

14.
Chinese Journal of Zoonoses ; 36(5):377-382, 2020.
Article in Chinese | GIM | ID: covidwho-824854

ABSTRACT

Coronavirus disease 2019 (COVID-19) has strong infectious power, and multi-generation clustered cases are easier to be appearing. To understand the relevant characteristics of multi-generation clustered cases of COVID-19, the epidemiological description and analysis of multi-generation clustered cases reported in Henan province were performed. The clustered epidemics of COVID-19 with more than 3 generation were selected from the public health emergency management information system of Henan province, as of February 23, 2020. The basic characteristic of cases;regional distribution, time distribution, clinical type distribution and incubation period were analyzed.

15.
Int J Epidemiol ; 49(4): 1085-1095, 2020 08 01.
Article in English | MEDLINE | ID: covidwho-615826

ABSTRACT

BACKGROUND: Despite many reports on the characteristics of coronavirus disease 2019 (COVID-19) in Wuhan, China, relatively little is known about the transmission features of COVID-19 outside Wuhan, especially at the provincial level. METHODS: We collected epidemiological, demographic, clinical, laboratory, radiological and occupation information, along with contact history, of 671 patients with laboratory-confirmed COVID-19 reported from January 23 to February 5, 2020, in Henan province, China. We described characteristics of these cases, compared the diagnostic accuracy and features of blood testing, computed tomography (CT) scans and X-rays, and analysed SARS-CoV-2 transmission sources and patients' occupations in Henan province. RESULTS: The mean age of patients in this case series was 43 years, 56.2% were male and 22.4% had coexisting medical disorders. The death rate was 0.3%. Fourteen patients did not show any symptoms. Lymphocyte percentage was associated with disease severity (χ2 = 6.71, P = 0.035) but had a large variation in each sample group. The mean time from illness onset to diagnosis was 5.6 days. A total of 330 patients had ever lived in or visited Wuhan, 150 had contact with confirmed cases, 323 had been to a hospital and 119 had been to a wet market. There were 33 patients who did not have a traceable transmission source, with 21.2% of these being farmers and 15.2% being workmen. CONCLUSIONS: Lymphocyte percentage was a sign of severe COVID-19 in general but was not a good diagnostic index. Longer time from illness onset to diagnosis was associated with higher COVID-19 severity, older age, higher likelihood of having coexisting cardiovascular diseases including hypertension, and being male. Farming was found to be a high-risk occupation in Henan province, China.


Subject(s)
Coronavirus Infections/epidemiology , Coronavirus , Lung/diagnostic imaging , Pneumonia, Viral/epidemiology , Adolescent , Adult , Aged , Betacoronavirus , COVID-19 , China/epidemiology , Coronavirus Infections/diagnosis , Coronavirus Infections/transmission , Cough/virology , Female , Fever/virology , Humans , Hypertension/epidemiology , Male , Middle Aged , Pandemics , Pneumonia, Viral/diagnosis , Pneumonia, Viral/transmission , Radiography, Thoracic , SARS-CoV-2 , Tomography, X-Ray Computed
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