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1.
Travel Med Infect Dis ; : 102451, 2022.
Article in English | PubMed | ID: covidwho-2027220
2.
Frontiers in Public Health ; 10:978159, 2022.
Article in English | MEDLINE | ID: covidwho-2023005

ABSTRACT

During the COVID-19 pandemic in 2020, a tuberculosis outbreak occurred in a university in eastern China, with 4,488 students and 421 staff on the campus. A 19-year-old student was diagnosed in August 2019. Later, the first round of screening was initiated among close contacts, but no active cases were found. Till September 2020, four rounds of screening were performed. Four rounds of screening were conducted on September 9, November 8, November 22-25 in 2019 and September 2020, with 0, 5, 0 and 43 cases identified, respectively. A total of 66 active tuberculosis were found in the same university, including 4 sputum culture-positive and 7 sputum smear-positive. The total attack rate of active tuberculosis was 1.34% (66/4909). The whole-genome sequencing showed that the isolates belonged to the same L2 sub-specie and were sensitive to all tested antituberculosis drugs. Delay detection, diagnosis and report of cases were the major cause of this university tuberculosis epidemic. More attention should be paid to the asymptomatic students in the index class. After the occurrence of tuberculosis cases in schools, multiple rounds of screening should be carried out, and preventive therapy should be applied in a timely manner.

3.
Frontiers in Public Health ; 10, 2022.
Article in English | Web of Science | ID: covidwho-2022935

ABSTRACT

ObjectiveFrom January 23rd, 2020, lock-down measures were adopted in Wuhan, China to stop the spread of COVID-19. However, due to the approach of the Spring Festival and the nature of COVID-19, more than 6 million permanent and temporary residents of Wuhan (who were potential carriers or spreaders of the virus), left the city before the lock-down measures were implemented. This study aims to explore whether and how the population inflow from Wuhan city impacted residents' confidence in controlling COVID-19 outbreaks at the destination cities. Study design and settingBased on questionnaire data and migration big data, a multiple regression model was developed to quantify the impact of the population inflow from Wuhan city on the sense of confidence of residents in controlling the COVID-19 outbreak at the destination cities. Scenarios were considered that varied residents' expected month for controlling COVID-19 outbreak at the destination cities, residents' confidence in controlling COVID-19 outbreak at the destination cities, and the overall indicators for the sense of confidence of residents in controlling COVID-19. A marginal effect analysis was also conducted to calculate the probability of change in residents' confidence in controlling the COVID-19 outbreak with per unit change in the population inflow from Wuhan city. ResultsThe impact of population inflow from Wuhan city on residents' expected month for controlling COVID-19 outbreak at the destination cities was positive and significant at the 1% level, while that on residents' confidence in controlling COVID-19 at the destination cities was negative and significant at the 1% level. Robustness checks, which included modifying the sample range and replacing measurement indicators of the population inflow from Wuhan city, demonstrated these findings were robust and credible. When the population inflow from Wuhan city increased by one additional unit, the probabilities of the variables "February" and "March" decreased significantly by 0.1023 and 0.1602, respectively, while the probabilities of "April," "May," "June," "July," "before the end of 2020," and "unknown" significantly increased by 0.0470, 0.0856, 0.0333, 0.0080, 0.0046, and 0.0840, respectively. Similarly, when the population inflow from Wuhan city increased by one additional unit, the probability of the variable "extremely confident" decreased by 0.1973. Furthermore, the probabilities of the variables "confident," "neutral," and "unconfident" significantly increased by 0.1392, 0.0224, and 0.0320, respectively. ConclusionThe population inflow from Wuhan city played a negative role in the sense of confidence of residents in controlling COVID-19 in the destination cities. The higher the population inflow from Wuhan city, the longer the residents' expected month for controlling COVID-19 outbreak at the destination cities became, and the weaker the residents' confidence in controlling the COVID-19 outbreak at the destination cities.

4.
Frontiers in Psychology ; 13:781274, 2022.
Article in English | MEDLINE | ID: covidwho-2022856

ABSTRACT

Background: Negative life events in middle school students have a significant impact on depression. However, the mechanism of this association is not fully understood. This study used rumination and perceived social support as mediating variables to explore the influence of negative life events on depression. Materials and methods: Due to the COVID-19 pandemic and social distancing, a convenient sampling method was adopted to collect information about middle school students in Shandong Province by means of online questionnaire. Adolescent Self-Rating Life Events Check List, Ruminative Responses Scale, Perceived Social Support Scale and Children's Depression Inventory were used. Descriptive statistics and correlation analysis were conducted for four variables of middle school students, including life events, depression, rumination thinking and perceived social support, and the chain mediated effect was tested by using process plug-in. All statistically analysis was conducted by SPSS 23.0. Results: 493 middle school students (16.7000 +/- 0.9500 years) including 343 female students (69.6000%) from Shandong Province recruited. Results showed that the total effect between life events and depression was significant (effect = 0.2535, 95%CI: 0.2146, 0.2924). The total indirect effect was significant (effect = 0.1700, 95%CI: 0.1349, 0.2072). The indirect effect was significant (effect = 0.0988, 95%CI: 0.0741, 0.1252) with rumination as the mediating variable. The indirect effect of pathway with perceived social support as the mediating variable was significant (effect = 0.0476, 95%CI: 0.0295, 0.0674). The indirect effect of pathway with rumination and perceived social support as mediating variables was also significant (effect = 0.0236, 95%CI: 0.0147, 0.0339). Conclusion: This study indicated that ruminant thinking and perceived social support had a significant chain mediating effect on adolescents' life events and depression. Life events can not only directly affect depressive emotions, but also indirectly affect depressive emotions by affecting ruminant thinking and perceived social support. The results of this study not only provide new directions for the relationship between life events and depression, but also provide possible approaches for future prevention and intervention of depression in middle school students.

5.
Frontiers in Pharmacology ; 13, 2022.
Article in English | Web of Science | ID: covidwho-2022839

ABSTRACT

Background: The coronavirus disease of 2019 (COVID-19) is a severe public health issue that has infected millions of people. The effective prevention and control of COVID-19 has resulted in a considerable increase in the number of cured cases. However, little research has been done on a complete metabonomic examination of metabolic alterations in COVID-19 patients following treatment. The current project pursues rigorously to characterize the variation of serum metabolites between healthy controls and COVID-19 patients with nucleic acid turning negative via untargeted metabolomics. Methods: The metabolic difference between 20 COVID-19 patients (CT >= 35) and 20 healthy controls were investigated utilizing untargeted metabolomics analysis employing High-resolution UHPLC-MS/MS. COVID-19 patients' fundamental clinical indicators, as well as health controls, were also collected. Results: Out of the 714 metabolites identified, 203 still significantly differed between COVID-19 patients and healthy controls, including multiple amino acids, fatty acids, and glycerophospholipids. The clinical indexes including monocytes, lymphocytes, albumin concentration, total bilirubin and direct bilirubin have also differed between our two groups of participators. Conclusion: Our results clearly showed that in COVID-19 patients with nucleic acid turning negative, their metabolism was still dysregulated in amino acid metabolism and lipid metabolism, which could be the mechanism of long-COVID and calls for specific post-treatment care to help COVID-19 patients recover.

6.
Front Pharmacol ; 13:779942, 2022.
Article in English | PubMed | ID: covidwho-2022832

ABSTRACT

Background: Although increasing clinical trials studying Shenfu injection (SFI) comprising panaxoside 0.8 mg/ml extracted from Panax ginseng C.A. Mey. and aconitine 0.1 mg/ml extracted from Aconitum carmichaeli Debeaux for elderly patients with severe pneumonia on biomarkers associated with COVID-19 progression are emerging, there is no evidence-based evaluation for the effect of SFI on elderly severe pneumonia. Objectives: To evaluate the effect of SFI on elderly patients with severe pneumonia providing hints for treating critical COVID-19, we conducted a systematic review and meta-analysis. Methods: Nine databases, namely, PubMed, EMBASE, Web of Science, Science Direct, Google Scholar, Wanfang, Chongqing VIP Database, CNKI, and SinoMed were used to search clinical trials reporting the effect of SFI as an adjuvant for elderly severe pneumonia on outcomes of interest. Primary outcomes were total effective rate, Acute Physiology and Chronic Health Evaluation (APACHE) II score, mortality, and safety. Secondary outcomes were predictors associated with COVID-19 progression. Duplicated or irrelevant articles with unavailable data were excluded. Cochrane Collaboration's tool was used to evaluate the risk of bias by two reviewers independently. All data were analyzed by Rev Man 5.4. Continuous variables were shown as weighted mean difference (WMD) or standard mean difference (SMD) with 95% confidence intervals (95% CI), whereas dichotomous data were calculated as the risk ratio (RR) with 95% CI. Results: We included 20 studies with 1, 909 participants, and the pooled data showed that compared with standard control, SFI could improve the total effective rate (RR = 1.25, 95% CI = 1.14-1.37, and n = 689), APACHE II score (WMD = -2.95, 95% CI = -3.35, -2.56, and n = 809), and predictors associated with COVID-19 progression (brain natriuretic peptide, creatine kinase, stroke volume, cardiac output, left ventricular ejection fraction, cardiac index, sE-selectin, von Willebrand factor, activated partial thromboplastin time, platelet counts, D-Dimer, procalcitonin, and WBC count). SFI may reduce mortality (RR = 0.52, 95% CI = 0.37-0.73, and n = 429) and safety concerns (RR = 0.29, 95% CI = 0.17-0.51, and n = 150) for elderly severe pneumonia. Conclusion: SFI as an adjuvant may improve the total effective rate, APACHE II score, gas exchange, and predictors associated with COVID-19 progression, reducing mortality and safety concerns for elderly patients with severe pneumonia.

7.
Frontiers in Bioengineering and Biotechnology ; 10, 2022.
Article in English | Web of Science | ID: covidwho-2022646

ABSTRACT

Digital PCR is the most advanced PCR technology. However, due to the high price of the digital PCR analysis instrument, this powerful nucleic acid detection technology is still difficult to be popularized in the general biochemistry laboratory. Moreover, one of the biggest disadvantages of commercial digital PCR systems is the poor versatility of reagents: each instrument can only be used for a few customized kits. Herein, we built a low-cost digital PCR system. The system only relies on low-cost traditional flat-panel PCR equipment to provide temperature conditions for commercial dPCR chips, and the self-made fluorescence detection system is designed and optically optimized to meet a wide range of reagent requirements. More importantly, our system not only has a low cost (< 8000 US dollars) but also has a much higher universality for nucleic acid detection reagents than the traditional commercial digital PCR system. In this study, several samples were tested. The genes used in the experiment were plasmids containing UPE-1a fragment, TP53 reference DNA, hepatitis B virus DNA, leukemia sample, SARS-COV-2 DNA, and SARS-COV-2 RNA. Under the condition that DNA can be amplified normally, the function of the dPCR system can be realized with simpler and low-price equipment. Some DNA cannot be detected by using the commercial dPCR system because of the special formula when it is configured as the reaction solution, but these DNA fluorescence signals can be clearly detected by our system, and the concentration can be calculated. Our system is more applicable than the commercial dPCR system to form a new dPCR system that is smaller and more widely applicable than commercially available machinery.

8.
Psychology Research and Behavior Management ; 15:2383-2390, 2022.
Article in English | Web of Science | ID: covidwho-2022228

ABSTRACT

Purpose: The novel coronavirus disease 2019 (COVID-19) pandemic has become a challenge for adolescents in China. This study aimed to explore the relationship between academic anxiety and self-esteem in Chinese candidates preparing for the college entrance examination during the COVID-19 pandemic and to examine the mechanism of mediating effect of self-regulated learning ability. Methods: A cross-sectional study was conducted among 293 college entrance examination candidates (including 170 females) from two middle schools in China using a voluntary, web-based, and anonymous questionnaire implemented via the Questionnaire Star app during COVID-19 prevalence in 2020.Results: This study found that 1) students in the high and low academic anxiety groups had different levels of self-regulated learning ability and self-esteem, 2) the academic anxiety, self-regulated learning ability, and self-esteem levels of students were significantly correlated and 3) after controlling the two independent variables of gender and subject type, academic anxiety had a significant negative predictive effect on self-esteem, and self-regulated learning ability played a mediating role between academic anxiety and self-esteem, where the mediating effect was 18.6%.Conclusion: Based on the observations of the present study, self-regulated learning capacity was a mediator between academic anxiety and self-esteem. These findings suggest an underlying process by which low academic anxiety may increase self-esteem in candidates preparing for the college entrance examination by increasing self-regulated learning ability.

9.
5th International Conference on Big Data and Education, ICBDE 2022 ; : 83-88, 2022.
Article in English | Scopus | ID: covidwho-2020383

ABSTRACT

In recent years, due to the impact of the coronavirus "COVID-19"pandemic crisis, obtaining a degree through online learning is attracting more and more people's attention. The research object of this article is the online master's degree program, which is a master-level education based on distance education. The enrollment targets are adults who have obtained a bachelor's degree or above, or are working adults, and the training form is mainly in the form of distance education. The development of the American online master's degree program started early and has gone through three stages of beginning, development and transformation. The development of online master's degree programs has important characteristics: the program provides from closed to open, the main provider from single to multiple, online education and traditional higher education from separation to integration.In the future, American master's degree programs will continue to be unbundled. © 2022 ACM.

10.
IEEE Journal of Biomedical & Health Informatics. PP ; 08:08, 2022.
Article in English | MEDLINE | ID: covidwho-2018932

ABSTRACT

Chest X-ray (CXR) is commonly performed as an initial investigation in COVID-19, whose fast and accurate diagnosis is critical. Recently, deep learning has a great potential in detecting people who are suspected to be infected with COVID-19. However, deep learning resulting with black-box models, which often breaks down when forced to make predictions about data for which limited supervised information is available and lack inter-pretability, still is a major barrier for clinical integration. In this work, we hereby propose a semantic-powered explainable model-free few-shot learning scheme to quickly and precisely diagnose COVID-19 with higher reliability and transparency. Specifically, we design a Report Image Explanation Cell (RIEC) to exploit clinically indicators derived from radiology reports as interpretable driver to introduce prior knowledge at training. Meanwhile, multi-task colla-borative diagnosis strategy (MCDS) is developed to construct [Formula: see text]-way [Formula: see text]-shot tasks, which adopts a cyclic and collaborative training approach for producing better generalization performance on new tasks. Extensive experiments demonstrate that the proposed scheme achieves competitive results (accuracy of 98.91%, precision of 98.95%, recall of 97.94% and F1-score of 98.57%) to diagnose COVID-19 and other pneumonia infected categories, even with only 200 paired CXR images and radiology reports for training. Furthermore, statistical results of comparative experiments show that our scheme provides an interpretable window into the COVID-19 diagnosis to improve the performance of the small sample size, the reliability and transparency of black-box deep learning mod-els. Our source codes will be released on https://github.com/AI-medical-diagnosis-team-of-JNU/SPEMFSL-Diagnosis-COVID-19.

11.
Signal Transduction and Targeted Therapy ; 7(1), 2022.
Article in English | Web of Science | ID: covidwho-2016658

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still rapidly spreading worldwide. Many drugs and vaccines have been approved for clinical use show efficacy in the treatment and prevention of SARS-CoV-2 infections. However, the emergence of SARS-CoV-2 variants of concern (VOCs), such as Delta (B.1.617.2) and the recently emerged Omicron (B.1.1.529), has seriously challenged the application of current therapeutics. Therefore, there is still a pressing need for identification of new broad-spectrum antivirals. Here, we further characterized a human antibody (58G6), which we previously isolated from a patient, with a broadly authentic virus-neutralizing activity that inhibits the Delta and Omicron variants with half-maximal inhibitory concentrations (IC50) of 1.69 ng/ml and 54.31 ng/ml, respectively. 58G6 shows prophylactic and therapeutic efficacy in hamsters challenged with the Delta and Omicron variants through nasal delivery. Notably, a very low dosage (2 mg/kg daily) of 58G6 efficiently prevented Omicron variant replication in the lungs. These advantages may overcome the efficacy limitation of currently approved neutralizing antibodies that can be administered only by intravenous injection. In general, 58G6 is a promising prophylactic and therapeutic candidate against current circulating VOCs and even future emerging mutants. To the best of our knowledge, 58G6 is one of the most potent neutralizing antibodies against Omicron, with a broader spectrum than those approved for clinical use. 58G6 could be developed as a nebulized therapy, which would be more cost effective and user friendly and enhance the clinical outcome compared to that obtained with direct nasal delivery.

12.
Viruses ; 14(8), 2022.
Article in English | MEDLINE | ID: covidwho-2010309

ABSTRACT

Porcine viral diarrhea diseases affect the swine industry, resulting in significant economic losses. Porcine epidemic diarrhea virus (PEDV) genotypes G1 and G2, and groups A and C of the porcine rotavirus, are major etiological agents of severe gastroenteritis and profuse diarrhea, particularly among piglets, with mortality rates of up to 100%. Based on the high prevalence rate and frequent co-infection of PEDV, RVA, and RVC, close monitoring is necessary to avoid greater economic losses. We have developed a multiplex TaqMan probe-based real-time PCR for the rapid simultaneous detection and differentiation of PEDV subtypes G1 and G2, RVA, and RVC. This test is highly sensitive, as the detection limits were 20 and 100 copies/μL for the G1 and G2 subtypes of PEDV, respectively, and 50 copies/μL for RVA and RVC, respectively. Eighty-eight swine clinical samples were used to evaluate this new test. The results were 100% in concordance with the standard methods. Since reassortment between porcine and human rotaviruses has been reported, this multiplex test not only provides a basis for the management of swine diarrheal viruses, but also has the potential to impact public health as well.

13.
Nat Commun ; 13, 2022.
Article in English | PMC | ID: covidwho-2008282

ABSTRACT

In addition to investigating the virology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), discovering the host–virus dependencies are essential to identify and design effective antiviral therapy strategy. Here, we report that the SARS-CoV-2 entry receptor, ACE2, conjugates with small ubiquitin-like modifier 3 (SUMO3) and provide evidence indicating that prevention of ACE2 SUMOylation can block SARS-CoV-2 infection. E3 SUMO ligase PIAS4 prompts the SUMOylation and stabilization of ACE2, whereas deSUMOylation enzyme SENP3 reverses this process. Conjugation of SUMO3 with ACE2 at lysine (K) 187 hampers the K48-linked ubiquitination of ACE2, thus suppressing its subsequent cargo receptor TOLLIP-dependent autophagic degradation. TOLLIP deficiency results in the stabilization of ACE2 and elevated SARS-CoV-2 infection. In conclusion, our findings suggest selective autophagic degradation of ACE2 orchestrated by SUMOylation and ubiquitination as a potential way to combat SARS-CoV-2 infection.

14.
Signal Transduct Target Ther ; 7, 2022.
Article in English | PMC | ID: covidwho-2008259

ABSTRACT

The Coronavirus Disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a global pandemic that seriously threatens health and socioeconomic development, but the existed antiviral drugs and vaccines still cannot yet halt the spread of the epidemic. Therefore, a comprehensive and profound understanding of the pathogenesis of SARS-CoV-2 is urgently needed to explore effective therapeutic targets. Here, we conducted a multiomics study of SARS-CoV-2-infected lung epithelial cells, including transcriptomic, proteomic, and ubiquitinomic. Multiomics analysis showed that SARS-CoV-2-infected lung epithelial cells activated strong innate immune response, including interferon and inflammatory responses. Ubiquitinomic further reveals the underlying mechanism of SARS-CoV-2 disrupting the host innate immune response. In addition, SARS-CoV-2 proteins were found to be ubiquitinated during infection despite the fact that SARS-CoV-2 itself didn’t code any E3 ligase, and that ubiquitination at three sites on the Spike protein could significantly enhance viral infection. Further screening of the E3 ubiquitin ligases and deubiquitinating enzymes (DUBs) library revealed four E3 ligases influencing SARS-CoV-2 infection, thus providing several new antiviral targets. This multiomics combined with high-throughput screening study reveals that SARS-CoV-2 not only modulates innate immunity, but also promotes viral infection, by hijacking ubiquitination-specific processes, highlighting potential antiviral and anti-inflammation targets.

15.
Lancet Reg Health West Pac ; 29:100592, 2022.
Article in English | PMC | ID: covidwho-2007928

ABSTRACT

Background: In early March 2022, a major outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant spread rapidly throughout Shanghai, China. Here we aimed to provide a description of the epidemiological characteristics and spatiotemporal transmission dynamics of the Omicron outbreak under the population-based screening and lockdown policies implemented in Shanghai. Methods: We extracted individual information on SARS-CoV-2 infections reported between January 1 and May 31, 2022, and on the timeline of the adopted non-pharmaceutical interventions. The epidemic was divided into three phases: i) sporadic infections (January 1–February 28), ii) local transmission (March 1–March 31), and iii) city-wide lockdown (April 1 to May 31). We described the epidemic spread during these three phases and the subdistrict-level spatiotemporal distribution of the infections. To evaluate the impact on the transmission of SARS-CoV-2 of the adopted targeted interventions in Phase 2 and city-wide lockdown in Phase 3, we estimated the dynamics of the net reproduction number (Rt). Findings: A surge in imported infections in Phase 1 triggered cryptic local transmission of the Omicron variant in early March, resulting in the largest outbreak in mainland China since the original wave. A total of 626,000 SARS-CoV-2 infections were reported in 99.5% (215/216) of the subdistricts of Shanghai until the end of May. The spatial distribution of the infections was highly heterogeneous, with 37% of the subdistricts accounting for 80% of all infections. A clear trend from the city center towards adjacent suburban and rural areas was observed, with a progressive slowdown of the epidemic spread (from 463 to 244 meters/day) prior to the citywide lockdown. During Phase 2, Rt remained well above 1 despite the implementation of multiple targeted interventions. The citywide lockdown imposed on April 1 led to a marked decrease in transmission, bringing Rt below the epidemic threshold in the entire city on April 14 and ultimately leading to containment of the outbreak. Interpretation: Our results highlight the risk of widespread outbreaks in mainland China, particularly under the heightened pressure of imported infections. The targeted interventions adopted in March 2022 were not capable of halting transmission, and the implementation of a strict, prolonged city-wide lockdown was needed to successfully contain the outbreak, highlighting the challenges for containing Omicron outbreaks. Funding: Key Program of the National Natural Science Foundation of China (82130093);Shanghai Rising-Star Program (22QA1402300).

16.
Environmental Toxicology ; 2022.
Article in English | EMBASE | ID: covidwho-2007115

ABSTRACT

Since the outbreak of COVID-19, widespread utilization of disinfectants has led to a tremendous increase in the generation of disinfection byproducts worldwide. Bromoacetic acid (BAA), one of the common disinfection byproducts in the environment, has triggered public concern because of its adverse effects on urinary system in mammals. Nevertheless, the BAA-induced nephrotoxicity and potential mechanism in birds still remains obscure. According to the detected content in the Taihu Lake Basin, the model of BAA exposure in chicken was established at doses of 0, 3, 300, 3000 μg/L for 4 weeks. Our results indicated that BAA exposure caused kidney swelling and structural disarrangement. BAA led to disorder in renal function (CRE, BUN, UA) and increased apoptosis (Bax, Bcl-2, caspase3). BAA suppressed the expression of mitochondrial biogenesis genes (PGC-1α, Nrf1, TFAM) and OXPHOS complex I genes (ND1, ND2, ND3, ND4, ND4L, ND5, ND6). Subsequently, BAA destroyed the expression of Nrf2 antioxidant reaction genes (Nrf2, Keap1, HO-1, NQO1, GCLM, GCLC). Furthermore, renal oxidative damage led to disorder in uric acid metabolism genes (Mrp2, Mrp4, Bcrp, OAT1, OAT2, OAT3) and exacerbated destruction in renal function. Overall, our study provided insights into the potential mechanism of BAA-induced nephrotoxicity, which were important for the clinical monitoring and prevention of BAA.

17.
Journal of Financial Economic Policy ; 2022.
Article in English | Web of Science | ID: covidwho-2005057

ABSTRACT

Purpose This study aims to provide a fresh look at banks as lenders in and extending past the COVID-19 crisis, with a particular focus on examining the results of recent work by Lei et al. (2020). Design/methodology/approach The authors' replication, as well as the original paper, uses a fixed-effects model on panel data. The authors discuss issues regarding data sources as well as use an array of panel data robustness checks to help ascertain an appropriate empirical specification for continued research of this type. Findings The authors show that the results of Lei et al. (2020) are sensitive to the data source, as well as the construction of the standard errors in their regression framework, with an appropriate specification uncovered through panel data statistical tests. The authors also provide some extensions to the original work by including interacted fixed-effects models and extending the sample period from 2020Q1 to 2021Q1, noting some changes in results. Originality/value The authors provide novel results on banks' lending constraints both at the onset of the COVID-19 pandemic and shortly thereafter. The study also provides an empirical framework for future studies conducted on similar panel data sets.

18.
JAMA Network Open ; 5(8):e2228008, 2022.
Article in English | MEDLINE | ID: covidwho-1999802

ABSTRACT

Importance: Several studies were conducted to estimate the average incubation period of COVID-19;however, the incubation period of COVID-19 caused by different SARS-CoV-2 variants is not well described. Objective: To systematically assess the incubation period of COVID-19 and the incubation periods of COVID-19 caused by different SARS-CoV-2 variants in published studies. Data Sources: PubMed, EMBASE, and ScienceDirect were searched between December 1, 2019, and February 10, 2022. Study Selection: Original studies of the incubation period of COVID-19, defined as the time from infection to the onset of signs and symptoms. Data Extraction and Synthesis: Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline, 3 reviewers independently extracted the data from the eligible studies in March 2022. The parameters, or sufficient information to facilitate calculation of those values, were derived from random-effects meta-analysis. Main Outcomes and Measures: The mean estimate of the incubation period and different SARS-CoV-2 strains. Results: A total of 142 studies with 8112 patients were included. The pooled incubation period was 6.57 days (95% CI, 6.26-6.88) and ranged from 1.80 to 18.87 days. The incubation period of COVID-19 caused by the Alpha, Beta, Delta, and Omicron variants were reported in 1 study (with 6374 patients), 1 study (10 patients), 6 studies (2368 patients) and 5 studies (829 patients), respectively. The mean incubation period of COVID-19 was 5.00 days (95% CI, 4.94-5.06 days) for cases caused by the Alpha variant, 4.50 days (95% CI, 1.83-7.17 days) for the Beta variant, 4.41 days (95% CI, 3.76-5.05 days) for the Delta variant, and 3.42 days (95% CI, 2.88-3.96 days) for the Omicron variant. The mean incubation was 7.43 days (95% CI, 5.75-9.11 days) among older patients (ie, aged over 60 years old), 8.82 days (95% CI, 8.19-9.45 days) among infected children (ages 18 years or younger), 6.99 days (95% CI, 6.07-7.92 days) among patients with nonsevere illness, and 6.69 days (95% CI, 4.53-8.85 days) among patients with severe illness. Conclusions and Relevance: The findings of this study suggest that SARS-CoV-2 has evolved and mutated continuously throughout the COVID-19 pandemic, producing variants with different enhanced transmission and virulence. Identifying the incubation period of different variants is a key factor in determining the isolation period.

19.
International Journal of Clinical and Experimental Medicine ; 15(7):231-235, 2022.
Article in English | EMBASE | ID: covidwho-1976313

ABSTRACT

Background: COVID-19 is caused by infection with a new form of coronavirus (SARS-CoV-2). The WHO raised the COVID-19 alert to the highest level. The virus is a highly contagious via human-to-human transmission. The median duration of viral shedding is 20.0 days. We report a long duration of viral shedding that was 32.0 days from illness onset in a patient with moderate COVID-19 admitted to Qianjiang Central Hospital. Case report: A 37-year-old patient sought medical advice while suffering from fever, dry cough, fatigue, dizziness, runny nose and diarrhoea. Five days before the visit, he had a history of travel from affected geographic areas. The patient had a positive RT-PCR test, and chest CT images showed multiple nodules and mixed ground-glass opacification with consolidation in bilaterally in the lungs. Laboratory findings showed that the lymphocyte and CD4+ counts were below the normal range. The patient was given antiviral treatment, including arbidol, lopinavir, IFN-α, and traditional Chinese medicine, and other necessary supportive care. All clinical symptoms and CT imaging manifestation ab-normalities resolved during the course of therapy. Conclusion: Although the positive RT-PCR tests were verified in consecutive upper respiratory specimens, the patient’s clinical symptoms, CT imaging findings, CD4+ lymphocyte counts, and IgG antibody levels had obviously improved. Positive tests may be detecting pieces of inactive viruses, which would not be transmissible in individual cases.

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