Porcine epidemic diarrhea virus (PEDV) is an intestinal coronavirus that can cause porcine epidemic diarrhea, leading to diarrhea, vomiting, weight loss, and even death in piglets. Due to the diversity of PEDV strains, traditional vaccines are difficult to sustainably and effectively prevent and control PEDV. This article reviews the strategies and mechanisms of active substances in regulating intracellular signaling pathways, viral proteins, and microbial metabolites to enhance the host immune function against PEDV. It emphasizes the prevention of PEDV resistance and the potential harm of PEDV breaking through interspecies barriers to the human society, aiming to provide reliable theoretical support for the development of new antiviral drugs or vaccines.
Porcine epidemic diarrhea virus/immunology* ; Animals ; Swine ; Swine Diseases/prevention & control* ; Antiviral Agents/pharmacology* ; Coronavirus Infections/virology* ; Viral Vaccines/immunology* ; Humans ; Signal Transduction

This study aims to establish an antibody detection method for porcine deltacoronavirus (PDCoV). The recombinant proteins PDCoV-N1 and PDCoV-N2 were expressed via the prokaryotic plasmid pColdII harboring the N gene sequence of the PDCoV strain CH/XJYN/2016. The reactivity and specificity of PDCoV-N1 and PDCoV-N2 with anti-PEDV sera were analyzed after the recombinant proteins were analyzed by SDS-PAGE and purified by the Ni-NTA Superflow Cartridge. Meanwhile, Western blotting and indirect immunofluorescence assay were carried out separately to validate the recombinant proteins PDCoV-N1 and PDCoV-N2. Finally, we established an indirect ELISA method based on the recombinant protein PDCoV-N2 after optimizing the conditions and tested the sensitivity, specificity, and reproducibility of the method. Then, the established method was employed to examine 102 clinical serum samples. The recombinant protein PDCoV-N2 showed low cross-reactivity with anti-PEDV sera. The optimal conditions of the indirect ELISA method based on PDCoV-N2 were as follows: the antigen coating concentration of 1.25 μg/mL and coating at 37 ℃ for 1 h; blocking by BSA overnight at 4 ℃; serum sample dilution at 1:50 and incubation at 37 ℃ for 1 h; secondary antibody dilution at 1:80 000 and incubation at 37 ℃ for 1 h; color development with TMB chromogenic solution at 37 ℃ for 10 min. The S/P value ≥ 0.45, ≤0.38, and between 0.45 and 0.38 indicated that the test sample was positive, negative, and suspicious, respectively. The testing results of the antisera against porcine epidemic diarrhea virus (PEDV), porcine circovirus 2 (PCV2), transmissible gastroenteritis virus (TGEV), foot-and-mouth disease virus (FMDV), and African swine fever virus (ASFV) showed that the S/P values were all less than 0.38. The testing results of the 800-fold diluted anti-PDCoV sera were still positive. The results of the inter- and intra-batch tests showed that the coefficients of variation of this method were less than 10%. Clinical serum sample test results showed the coincidence rate between this method and neutralization test was 94.12%. In this study, an ELISA method for the detection of anti-PDCoV antibodies was successfully established based on the truncated N protein of PDCoV. This method is sensitive, specific, stable, and reproducible, serving as a new method for the clinical diagnosis of PDCoV.
Animals ; Enzyme-Linked Immunosorbent Assay/methods* ; Swine ; Antibodies, Viral/blood* ; Recombinant Proteins/genetics* ; Deltacoronavirus/isolation & purification* ; Coronavirus Infections/virology* ; Swine Diseases/diagnosis* ; Coronavirus Nucleocapsid Proteins ; Sensitivity and Specificity

Blood Coagulation ; Blood Coagulation Disorders ; virology ; Coronavirus Infections ; complications ; Humans ; Pandemics ; Pneumonia, Viral ; complications

BACKGROUND: Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans. METHODS: We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed. RESULTS: Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown β-CoV strain in all five patients, with 99.8% to 99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6% to 87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor. CONCLUSION A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.
Adult ; Aged ; Betacoronavirus ; genetics ; isolation & purification ; Coronavirus Infections ; diagnostic imaging ; therapy ; virology ; Female ; Humans ; Male ; Middle Aged ; Pandemics ; Pneumonia, Viral ; diagnostic imaging ; therapy ; virology ; Tomography, X-Ray ; Treatment Outcome

According to the classification of traditional Chinese medicine syndromes of coronavirus disease 2019 by the national competent authority, this study determined that human coronavirus 229 E(HCoV-229 E) was infected in a mouse model of cold and dampness syndrome, so as to build the human coronavirus pneumonia with pestilence attacking lung syndrome model. The model can simulate the traditional Chinese medicine treatment of common disease syndromes in Coronavirus Disease 2019 Diagnosis and Treatment Program(the sixth edition for trial). Specific steps were as follows. ABALB/c mouse model of cold and dampness syndrome was established, based on which, HCoV-229 E virus was infected; then the experiment was divided into normal control group, infection control group, cold-dampness control group, cold-dampness infection group(the model group), high-dose Chaiyin Particles group(8.8 g·kg~(-1)·d~(-1)), and low-dose Chaiyin Particles group(4.4 g·kg~(-1)·d~(-1)). On the day of infection, Chaiyin Particles was given for three consecutive days. Lung tissues were collected the day after the last dose, and the lung index and inhibition rate were calculated. The nucleic acid of lung tissue was extracted, and the HCoV-229 E virus load was detected by Real-time fluorescent quantitative RT-PCR. Blood leukocytes were separated, and the percentage of T and B lymphocytes was detected by flow cytometry. Lung tissue protein was extracted, and IL-6, IL-10, TNF-α and IFN-γ contents were detected by ELISA. High and low-dose Chaiyin Particles significantly reduced the lung index(P<0.01) of mice of human coronavirus pneumonia with pestilence attacking the lung syndrome, and the inhibition rates were 61.02% and 55.45%, respectively. Compared with the model control group, high and low-dose Chaiyin Particles significantly increased cross blood CD4~+ T lymphocytes, CD8~+T lymphocytes and total B lymphocyte percentage(P<0.05, P<0.01), and reduced IL-10, TNF-α and IFN-γ levels in lungs(P<0.01). In vitro results showed that TC_(50), TC_0, IC_(50) and TI of Chaiyin Particles were 4.46 mg·mL~(-1), 3.13 mg·mL~(-1), 1.12 mg·mL~(-1) and 4. The control group of in vitro culture cells had no HCoV-229 E virus nucleic acid expression. The expression of HCoV-229 E virus nucleic acid in the virus control group was 1.48×10~7 copies/mL, and Chaiyin Particles significantly reduced HCoV-229 E expression at doses of 3.13 and 1.56 mg·mL~(-1), and the expression of HCoV-229 E nucleic acid was 9.47×10~5 and 9.47×10~6 copies/mL, respectively. Chaiyin Particles has a better effect on the mouse model with human coronavirus pneumonia with pestilence attacking the lung syndrome, and could play a role by enhancing immunity, and reducing inflammatory factor expression.
Animals ; Coronavirus 229E, Human ; Coronavirus Infections ; immunology ; therapy ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Lung ; immunology ; virology ; Medicine, Chinese Traditional ; Mice ; Mice, Inbred BALB C

Since December 2019, a series of highly infectious cases of unexplained pneumonia have been discovered in Wuhan, Hubei Province, which have been confirmed as '2019 corona virus disease' caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 virus can invade many human systems including the lungs. Patients with central nervous system involvement may show a series of neurological symptoms, which is easy to be misdiagnosed and neglected, thereby increasing the risk of SARS-CoV-2 transmission. Hereditary ataxia is a large group of neurodegenerative diseases with great clinical and genetic heterogeneity and high mortality and disability. In view of the seriousness of the COVID-19 epidemic, a series of prevention and control measures adopted by the government have restricted the follow-up, diagnosis and treatment of patients by the hospitals, which has a great impact on their mental and physical health. In order to standardize the management of patients during the prevention and control of COVID-19 epidemic, the Specialized Committee of Neurogenetics of the Neurophysician Branch of Chinese Medical Doctor Association has formulated this consensus, with an aim to help patients to overcome the difficulties and pass the epidemic prevention period safely.
Betacoronavirus ; China ; epidemiology ; Consensus ; Coronavirus Infections ; complications ; epidemiology ; Epidemics ; Health Status ; Humans ; Mental Health ; Nervous System Diseases ; virology ; Pandemics ; Pneumonia, Viral ; complications ; epidemiology ; Spinocerebellar Degenerations ; complications ; diagnosis ; prevention & control ; therapy

OBJECTIVE: To investigate the clinical outcome of patients with moderate type of coronavirus disease 2019 (COVID-19) after discharge by retesting viral nucleic acid. METHODS: Seven patients with moderate COVID-19 met the discharge criteria enacted by National Health Commission were quarantined in hospital for 7 days, then continuously quarantined at home for 4 weeks after discharged. During the quarantined period, the symptoms and signs were documented, and sputum or nasal swab and feces samples were collected to test SARS-CoV-2 nucleic acid by RT-PCR method. RESULTS: There was no symptoms and signs during the quarantine period in all 7 patients. However, respiratory swabs from 3 patients were confirmed positive of SARS-CoV-2 nucleic acid at 5 to 7 days after they met the discharge criteria. CONCLUSIONS There is a relatively high incidence of positive viral nucleic acid in patients met the discharge criteria, and it is suggested that patients met the current discharge criteria should be quarantined in hospital for another 7 days and the follow-up viral testing is necessary.
Betacoronavirus ; isolation & purification ; Coronavirus Infections ; diagnosis ; Feces ; chemistry ; virology ; Follow-Up Studies ; Humans ; Pandemics ; Patient Discharge ; statistics & numerical data ; Pneumonia, Viral ; diagnosis ; Quarantine ; statistics & numerical data ; RNA, Viral ; analysis ; Reverse Transcriptase Polymerase Chain Reaction ; Time Factors

OBJECTIVE: To compare the diagnostic efficacy among three RT-PCR test kits for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid detection. METHODS: The throat swab samples from 40 hospitalized patients clinically diagnosed as coronavirus disease 2019 (COVID-19) and 16 hospitalized non-COVID-19 patients were recruited. The SARS-CoV-2 nucleic acid was detected in throat swab samples with RT-PCR test kits from Sansure Biotech ("Sansure" for short), Jiangsu Bioperfectus Technologies ("Bioperfectus" for short) and BGI Genomics ("BGI" for short). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and Kappa value were analyzed. The viral nucleic acid was extracted from the throat swab samples by one-step cleavage and magnetic bead methods, and the efficacy of two extraction methods was also compared. The results of magnetic bead method for nucleic acid extraction by two different extractors (Sansure Natch CS S12C Fully Automated Nucleic Acid Extraction System vs. Tianlong NP968-C Nucleic Acid Extractor) were also compared. RESULTS: The sensitivity, specificity, PPV, NPV and kappa value were 95.00%, 87.50%, 95.00%, 87.50%and 0.825 for Sansure kit; 90.00%, 87.50%, 94.74%, 77.78%and 0.747 for the Bioperfectus kit, and 82.50%, 81.25%, 91.67%, 65.00%and 0.593 for the BGI kit, respectively. The positive, negative and total coincident rates and kappa value of viral nucleic acid detection results using the samples extracted by one-step cleavage and magnetic bead methods were 95.24%, 100.00%, 96.43%and 0.909, respectively, but the one-step cleavage method took only 25 min, while the magnetic bead method required 180 min. The positive, negative and total coincident rates and kappa value of viral nucleic acid detection results using the samples extracted by the two different nucleic acid extractors were 85.00%, 100.00%, 89.29% and 0.764, respectively. CONCLUSIONS The detection efficacy for SARS-CoV-2 nucleic acid by the Sansure kit is relatively higher and the one-step cleavage method has advantages of convenient operation and less time consuming.
Betacoronavirus ; genetics ; isolation & purification ; Coronavirus Infections ; diagnosis ; virology ; Humans ; Pandemics ; Pneumonia, Viral ; diagnosis ; virology ; RNA, Viral ; genetics ; isolation & purification ; Reagent Kits, Diagnostic ; standards

The current epidemic situation of coronavirus disease 2019 (COVID-19) still remained severe. As the National Clinical Research Center for Infectious Diseases, the First Affiliated Hospital of Zhejiang University School of Medicine is the primary medical care center for COVID-19 in Zhejiang province. Based on the present expert consensus carried out by National Health Commission and National Administration of Traditional Chinese Medicine, our team summarized and established an effective treatment strategy centered on "Four-Anti and Two-Balance" for clinical practice. The "Four-Anti and Two-Balance" strategy included antivirus, anti-shock, anti-hyoxemia, anti-secondary infection, and maintaining of water, electrolyte and acid base balance and microecological balance. Meanwhile, integrated multidisciplinary personalized treatment was recommended to improve therapeutic effect. The importance of early viralogical detection, dynamic monitoring of inflammatory indexes and chest radiograph was emphasized in clinical decision-making. Sputum was observed with the highest positive rate of RT-PCR results. Viral nucleic acids could be detected in 10%patients' blood samples at acute period and 50%of patients had positive RT-PCR results in their feces. We also isolated alive viral strains from feces, indicating potential infectiousness of feces.Dynamic cytokine detection was necessary to timely identifying cytokine storms and application of artificial liver blood purification system. The "Four-Anti and Two-Balance" strategy effectively increased cure rate and reduced mortality. Early antiviral treatment could alleviate disease severity and prevent illness progression, and we found lopinavir/ritonavir combined with abidol showed antiviral effects in COVID-19. Shock and hypoxemia were usually caused by cytokine storms. The artificial liver blood purification system could rapidly remove inflammatory mediators and block cytokine storm.Moreover, it also favored the balance of fluid, electrolyte and acid-base and thus improved treatment efficacy in critical illness. For cases of severe illness, early and also short period of moderate glucocorticoid was supported. Patients with oxygenation index below 200 mmHg should be transferred to intensive medical center. Conservative oxygen therapy was preferred and noninvasive ventilation was not recommended. Patients with mechanical ventilation should be strictly supervised with cluster ventilator-associated pneumonia prevention strategies. Antimicrobial prophylaxis was not recommended except for patients with long course of disease, repeated fever and elevated procalcitonin (PCT), meanwhile secondary fungal infection should be concerned.Some patients with COVID-19 showed intestinal microbial dysbiosis with decreased probiotics such as and , so nutritional and gastrointestinal function should be assessed for all patients.Nutritional support and application of prebiotics or probiotics were suggested to regulate the balance of intestinal microbiota and reduce the risk of secondary infection due to bacterial translocation. Anxiety and fear were common in patients with COVID-19. Therefore,we established dynamic assessment and warning for psychological crisis. We also integrated Chinese medicine in treatment to promote disease rehabilitation through classification methods of traditional Chinese medicine. We optimized nursing process for severe patients to promote their rehabilitation. It remained unclear about viral clearance pattern after the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Therefore, two weeks' quarantine for discharged patients was required and a regular following up was also needed.The Zhejiang experience and suggestions have been implemented in our center and achieved good results. However, since COVID-19 was a newly emerging disease, more work was warranted to improve strategies of prevention, diagnosis and treatment for COVID-19.
Betacoronavirus ; isolation & purification ; China ; epidemiology ; Coronavirus Infections ; diagnosis ; epidemiology ; therapy ; virology ; Disease Management ; Early Diagnosis ; Feces ; virology ; Humans ; Pandemics ; Pneumonia, Viral ; diagnosis ; epidemiology ; therapy ; virology ; Sputum ; virology

The three known human highly pathogenic coronaviruses are severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus, (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Human highly pathogenic coronaviruses are composed of non-structural proteins, structural proteins and accessory proteins. Viral particles recognize host receptors via spike glycoprotein (S protein), enter host cells by membrane fusion, replicate in host cells through large replication-transcription complexes, and promote proliferation by interfering with and suppressing the host's immune response. Human highly pathogenic coronaviruses are hosted by humans and vertebrates. Viral particles are transmitted through droplets, contact and aerosols or likely through digestive tract, urine, eyes and other routes. This review discusses the mechanisms of proliferation and transmission of highly pathogenic human coronaviruses based on the results of existing research, providing basis for future study on interrupting the transmission and pathogenicity of human highly pathogenic coronaviruses.
Animals ; Betacoronavirus ; physiology ; Coronavirus Infections ; immunology ; transmission ; virology ; Humans ; Middle East Respiratory Syndrome Coronavirus ; physiology ; Pandemics ; Pneumonia, Viral ; immunology ; transmission ; virology ; SARS Virus ; physiology ; Virus Replication ; physiology