Epidemiological and clinical characteristics of 40 cases of COVID-19 outside Hubei Province, China

To explore characteristics of patients with pneumonia infected by 2019 Novel Coronavirus (COVID-19) in 2019 outside Hubei Province, China. 40 patients with pneumonia infected by COVID-19 which were confirmed by COVID-19 nucleic acid test were included. Procalcitonin (PCT), serum amyloid A (SAA), C-reactive protein (CRP) and computed tomography (CT) manifestations were analyzed. 40% of patients had clear contact history with Wuhan or other areas of Hubei Province. 60% of patients were clustered diseases and 40% were imported cases. 75% of patients had initial fever, 7.5% had cough, 5% had sore throat at first. 45% had decreased lymphocyte count, 72.5% and 55% patients had increased levels of SAA and CRP. 72.5% of the patients showed multiple ground glass lesions in one or two lungs on chest CT. 90% of the patients with pneumonia are of the common type, and a-interferon atomization inhalation combined with Lopinavir/Ritonavir tablets were given to patients during treatment. 62.5% of the patients were treated with antibiotics, and 15% with hormone. All patients improved after treatment, and 14 patients were cured and discharged. Family cluster infection and asymptomatic infection may be the main way of spreading of COVID-19 pneumonia outside Hubei Province in China.

Case study of the Beijing 2022 Olympic Winter Games: Implications for global mass gathering events amidst the COVID-19 pandemic.

Objective: This study aimed to evaluate the public health countermeasures against coronavirus disease 2019 (COVID-19) that are important for organizing mass gathering events (MGEs) during a pandemic and to identify the practices suitable for application at future MGEs. Methods: This study analyzed data from the Beijing 2022 Olympic Winter Games. The aforementioned analysis was conducted from the viewpoints of overseas stakeholders and Chinese residents. The comprehensive set of countermeasures established to prevent the transmission of the COVID-19 pandemic comprised the bubble strategy, the three-layer testing strategy (pre-departure testing, testing at the airport, and daily screening), the mandatory wearing of N95 masks, and mandatory vaccination. Findings: A total of 437 positive cases within the bubble were reported during the Games, of which 60.6% were detected through screening at the airport and 39.4% were detected through routine screening. Nearly, 92.0% of the positive cases were detected within 7 days of arrival in China, and 80.8% of the cases had already been identified before the Opening Ceremony of the Games. Outside the bubble, no Games stakeholders were infected and no spectator contracted COVID-19. The bubble strategy, the three-layer testing strategy, the mandatory wearing of N95 masks, and mandatory vaccination are promising countermeasures to prevent the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during MGEs. Conclusion: Public health countermeasures introduced during the Beijing 2022 Olympic Winter Games were proven to be useful. The success in delivering and organizing the Games instills confidence and leaves a public health legacy for future MGEs amid the pandemic of COVID-19 or future emerging infectious diseases.

GlPS1 overexpression accumulates coumarin secondary metabolites in transgenic Arabidopsis.

The dried root of Glehnia littoralis is a traditional Chinese herbal medicine mainly used to treat lung diseases and plays an important role in fighting coronavirus disease 2019 pneumonia in China. This study focused on the key enzyme gene GlPS1 for furanocoumarin synthesis in G. littoralis. In the 35S:GlPS1 transgenic Arabidopsis study, the Arabidopsis thaliana-overexpressing GlPS1 gene was more salt-tolerant than Arabidopsis in the blank group. Metabolomics analysis showed 30 differential metabolites in Arabidopsis, which overexpressed the GlPS1 gene. Twelve coumarin compounds were significantly upregulated, and six of these coumarin compounds were not detected in the blank group. Among these differential coumarin metabolites, isopimpinellin and aesculetin have been annotated by the Kyoto Encyclopedia of Genes and Genomes and isopimpinellin was not detected in the blank group. Through structural comparison, imperatorin was formed by dehydration and condensation of zanthotoxol and a molecule of isoprenol, and the difference between them was only one isoprene. Results showed that the GlPS1 gene positively regulated the synthesis of coumarin metabolites in A. thaliana and at the same time improved the salt tolerance of A. thaliana. Supplementary Information: The online version contains supplementary material available at 10.1007/s11240-022-02427-w.

Highly pathogenic coronavirus N protein aggravates inflammation by MASP-2-mediated lectin complement pathway overactivation.

Excessive inflammatory responses contribute to the pathogenesis and lethality of highly pathogenic human coronaviruses, but the underlying mechanism remains unclear. In this study, the N proteins of highly pathogenic human coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV), middle east respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), were found to bind MASP-2, a key serine protease in the lectin pathway of complement activation, resulting in excessive complement activation by potentiating MBL-dependent MASP-2 activation, and the deposition of MASP-2, C4b, activated C3 and C5b-9. Aggravated inflammatory lung injury was observed in mice infected with adenovirus expressing the N protein. Complement hyperactivation was also observed in SARS-CoV-2-infected patients. Either blocking the N protein:MASP-2 interaction, MASP-2 depletion or suppressing complement activation can significantly alleviate N protein-induced complement hyperactivation and lung injury in vitro and in vivo. Altogether, these data suggested that complement suppression may represent a novel therapeutic approach for pneumonia induced by these highly pathogenic coronaviruses.

Detection of co-infection of porcine circovirus and porcine epidemic diarrhea virus

In this study, 650 tissue samples which were collected from 16 pig farms in Hubei Province, were used to detect porcine circovirus (PCV) and Porcine epidemic diarrhea virus (PEDV). The results showed that the positive rates of PCV1, PCV2, PCV3 and PEDV single infection were 1.08%, 4.15%, 2.46% and 6.46%, respectively. In the double infections, PEDV+PCV2 had the highest positive rate of 3.54%, followed by PCV2+PCV3, with a positive rate of 1.54%. In multiple infections, PEDV+PCV2+PCV3 had the highest positive rate of 2.00%. The results indicated that the positive rates of PEDV and PCV were decreased compared with the previous studies, but the prevalence of PEDV and PCV was still wide in Hubei Province, and most of which were co-infection.

Epidemic and Evolutionary Characteristics of Swine Enteric Viruses in South-Central China from 2018 to 2021.

Swine enteric viruses are a major cause of piglet diarrhea, causing a devastating impact on the pork industry. To further understand the molecular epidemiology and evolutionary diversity of swine enteric viruses, we carried out a molecular epidemiological investigation of swine enteric viruses (PEDV, PDCoV, PoRVA, and TGEV) on 7107 samples collected from pig farms in south-central China. The results demonstrated that PEDV is the predominant pathogen causing piglet diarrhea, and its infection occurs mainly in relatively cold winter and spring in Hunan and Hubei provinces. The positive rate of PEDV showed an abnormal increase from 2020 to 2021, and that of PoRVA and PDCoV exhibited gradual increases from 2018 to 2021. PEDV-PoRVA and PEDV-PDCoV were the dominant co-infection modes. A genetic evolution analysis based on the PEDV S1 gene and ORF3 gene revealed that the PEDV GII-a is currently epidemic genotype, and the ORF3 gene of DY2020 belongs to a different clade relative to other GII-a strains isolated in this study. Overall, our results indicated that the variant PEDV GII-a is the main pathogen of piglet diarrhea with a trend of outbreak. G9 is the dominant PoRVA genotype and has the possibility of outbreak as well. It is therefore critical to strengthen the surveillance of PEDV and PoRVA, and to provide technical reserves for the prevention and control of piglet diarrhea.

SARS-CoV-2 N Protein Antagonizes Stress Granule Assembly and IFN Production by Interacting with G3BPs to Facilitate Viral Replication.

SARS-CoV-2 is the causative agent of the ongoing pandemic of coronavirus disease 2019 (COVID-19) and poses a significant threat to global health. N protein (NP), which is a major pathogenic protein among betacoronaviruses, binds to the viral RNA genome to allow viral genome packaging and viral particle release. Recent studies showed that NP antagonizes interferon (IFN) induction and mediates phase separation. Using live SARS-CoV-2 viruses, this study provides solid evidence showing that SARS-CoV-2 NP associates with G3BP1 and G3BP2 in vitro and in vivo. NPSARS-CoV-2 could efficiently suppress G3BP-mediated SG formation and potentiate viral infection by overcoming G3BP1-mediated antiviral innate immunity. G3BP1 conditional knockout mice (g3bp1fl/fL, Sftpc-Cre) exhibit significantly higher lung viral loads after SARS-CoV-2 infection than wild-type mice. Our findings contribute to the growing body of knowledge regarding the pathogenicity of NPSARS-CoV-2 and provide insight into new therapeutics targeting NPSARS-CoV-2. IMPORTANCE In this study, by in vitro assay and live SARS-CoV-2 virus infection, we provide solid evidence that the SARS-CoV-2 NP associates with G3BP1 and G3BP2 in vitro and in vivo. NPSARS-CoV-2 could efficiently suppress G3BP-mediated SG formation and potentiate viral infection by overcoming antiviral innate immunity mediated by G3BP1 in A549 cell lines and G3BP1 conditional knockout mice (g3bp1-cKO) mice, which provide in-depth evidence showing the mechanism underlying NP-related SARS-CoV-2 pathogenesis through G3BPs.

The MERS-CoV N Protein Regulates Host Cytokinesis and Protein Translation via Interaction With EF1A.

Middle East respiratory syndrome coronavirus (MERS-CoV), a pathogen causing severe respiratory disease in humans that emerged in June 2012, is a novel beta coronavirus similar to severe acute respiratory syndrome coronavirus (SARS-CoV). In this study, immunoprecipitation and proximity ligation assays revealed that the nucleocapsid (N) protein of MERS-CoV interacted with human translation elongation factor 1A (EF1A), an essential component of the translation system with important roles in protein translation, cytokinesis, and filamentous actin (F-actin) bundling. The C-terminal motif (residues 359-363) of the N protein was the crucial domain involved in this interaction. The interaction between the MERS-CoV N protein and EF1A resulted in cytokinesis inhibition due to the formation of inactive F-actin bundles, as observed in an in vitro actin polymerization assay and in MERS-CoV-infected cells. Furthermore, the translation of a CoV-like reporter mRNA carrying the MERS-CoV 5'UTR was significantly potentiated by the N protein, indicating that a similar process may contribute to EF1A-associated viral protein translation. This study highlights the crucial role of EF1A in MERS-CoV infection and provides new insights into the pathogenesis of coronavirus infections.

Influence of isolation measures for patients with mild symptoms on the spread of COVID-19.

During the transmission of COVID-19, the hospital isolation of patients with mild symptoms has been a concern. In this paper, we use a differential equation model to describe the propagation of COVID-19, and discuss the effects of intensity of hospital isolation and moment of taking measures on development of the epidemic. The results show that isolation measures can significantly reduce the epidemic final size and the number of dead, and the greater the intensity of measures, the better, but duration of the epidemic will be prolonged. Whenever isolation measures are taken, the epidemic final size and the number of dead can be reduced. In early stage of the epidemic, taking measures one day later has little impact, but after a certain period, if taking measures one day later, the epidemic final size and the number of dead increase sharply. Taking measures as early as possible makes the maximum number of patients appear later, which is conducive to expanding medical bed resources and reducing the pressure on medical resource demand. As long as possible, high-intensity isolation measures should be taken in time for patients with mild symptoms.