Clinical Effect of Yinhuang Qingfei Capsules in Treatment of Asymptomatic and Mild/Common Severe Acute Respiratory Syndrome Coronavirus 2 Infection:An Analysis of 242 Cases

[Objectives]To investigate the clinical effect of Yinhuang Qingfei capsules in the treatment of asymptomatic and mild/common severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.[Methods]A total of 362 patients with SARS-CoV-2 infection were divided into the treatment group with 242 patients and control group with 120 patients according to their treatment regimen.The patients in the control group were given standard treatment regimen and those in the treatment group were given Yinhuang Qingfei capsules in addition to the treatment in the control group.The two groups were observed in terms of average length of hospital stay,mean time for nucleic acid clearance,TCM syndrome score,and progression to severe/critical illness,and clinical outcome was compared between the two groups.[Results]There was a significant difference in the overall response rate between the treatment group and the control group[97.52%(236/242)vs 95.00%(114/120),P<0.05].Compared with the control group,the treatment group had significantly shorter length of hospital stay and time for nucleic acid clearance(P<0.05).After 7 days of treatment,both groups had a significant change in TCM syndrome score,and there was a significant difference in TCM syndrome score between the two groups(P<0.05);after 15 days of treatment,both groups had a TCM syndrome score of 0.Progression to severe/critical illness was not observed in either group.[Conclusions]Compared with the standard treatment regimen alone,standard treatment regimen combined with Yinhuang Qingfei capsules can effectively shorten the length of hospital stay and time for nucleic acid clearance and improve TCM symptoms in patients with asymptomatic and mild/common SARS-CoV-2 infection.

Severe acute respiratory syndrome coronavirus 2 may cause liver injury via Na^(+)/H^(+) exchanger

The liver has many significant functions,such as detoxification,the urea cycle,gluconeogenesis,and protein synthesis.Systemic diseases,hypoxia,infections,drugs,and toxins can easily affect the liver,which is extremely sensitive to injury.Systemic infection of severe acute respiratory syndrome coronavirus 2 can cause liver damage.The primary regulator of intracellular pH in the liver is the Na+/H+exchanger(NHE).Physiologically,NHE protects hepatocytes from apoptosis by making the intracellular pH alkaline.Severe acute respiratory syndrome coronavirus 2 increases local angiotensin II levels by binding to angiotensinconverting enzyme 2.In severe cases of coronavirus disease 2019,high angiotensin II levels may cause NHE overstimulation and lipid accumulation in the liver.NHE overstimulation can lead to hepatocyte death.NHE overstimulation may trigger a cytokine storm by increasing proinflammatory cytokines in the liver.Since the release of proinflammatory cytokines such as interleukin-6 increases with NHE activation,the virus may indirectly cause an increase in fibrinogen and D-dimer levels.NHE overstimulation may cause thrombotic events and systemic damage by increasing fibrinogen levels and cytokine release.Also,NHE overstimulation causes an increase in the urea cycle while inhibiting vitamin D synthesis and gluconeogenesis in the liver.Increasing NHE3 activity leads to Na+loading,which impairs the containment and fluidity of bile acid.NHE overstimulation can change the gut microbiota composition by disrupting the structure and fluidity of bile acid,thus triggering systemic damage.Unlike other tissues,tumor necrosis factor-alpha and angiotensin II decrease NHE3 activity in the intestine.Thus,increased luminal Na+leads to diarrhea and cytokine release.Severe acute respiratory syndrome coronavirus 2-induced local and systemic damage can be improved by preventing virus-induced NHE overstimulation in the liver.

Fear can be more harmful than the severe acute respiratory syndrome coronavirus 2 in controlling the corona virus disease 2019 epidemic

The current corona virus disease 2019 outbreak caused by severe acute respiratory syndrome coronavirus 2 started in Wuhan,China in December 2019 and has put the world on alert.To safeguard Chinese citizens and to strengthen global health security,China has made great efforts to control the epidemic.Many in the global community have joined China to limit the epidemic.However,discrimination and prejudice driven by fear or misinformation have been flowing globally,superseding evidence and jeopardizing the anti-severe acute respiratory syndrome coronavirus 2 efforts.We analyze this phenomenon and its underlying causes and suggest practical solutions.

Biology of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and the humoral immunoresponse:a systematic review of evidence to support global policy-level actions and research

Background Both population-level epidemiological data and individual-level biological data are needed to control the coronavirus disease 2019(COVID-19)pandemic.Population-level data are widely available and efforts to combat COVID-19 have generated proliferate data on the biology and immunoresponse to the causative pathogen,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).However,there remains a paucity of systemized data on this subject.Objective In this review,we attempt to extract systemized data on the biology and immuno-response to SARS-CoV-2 from the most up-to-date peer-reviewed studies.We will focus on the biology of the virus and immunological variations that are key for determining long-term immunity,transmission potential,and prognosis.Data Sources and Methods Peer-reviewed articles were sourced from the PubMed database and by snowballing search of selected publications.Search terms included:“Novel Coronavirus”OR“COVID-19”OR“SARS-CoV-2”OR“2019-nCoV”AND“Immunity”OR“Immune Response”OR“Antibody Response”OR“Immunologic Response”.Studies published from December 31,2019 to December 31,2020 were included.To ensure validity,papers in pre-print were excluded.Results Of 2889 identified papers,36 were included.Evidence from these studies suggests early seroconversion in patients infected with SARS-CoV-2.Antibody titers appear to markedly increase two weeks after infection,followed by a plateau.A more robust immune response is seen in patients with severe COVID-19 as opposed to mild or asymptomatic presentations.This trend persists with regard to the length of antibody maintenance.However,overall immunity appears to wane within two to three months post-infection.Conclusion Findings of this study indicate that immune responses to SARS-CoV-2 follow the general pattern of viral infection.Immunity generated through natural infection appears to be short,suggesting a need for long-term efforts to control the pandemic.Antibody testing will be essential to gauge the epidemic and inform decision-making on effective strategies for treatment and prevention.Further research is needed to illustrate immunoglobulin-specific roles and neutralizing antibody activity.

Severe Acute Respiratory Syndrome Coronavirus 2 Infection as A Risk Factor for Thromboembolic and Acute Ischemic Stroke:A Case Report

Increasing evidence reports a greater incidence of stroke in patients with coronavirus disease 2019(COVID-19)than in the non-COVID-19 population and suggests that severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection represents a risk factor for thromboembolic and acute ischemic stroke.Elderly people have higher risk factors for acute ischemic stroke or embolic vascular events,and advanced age is strongly associated with severe COVID-19 and death.We reported,instead,a case of an ischemic stroke in a young woman during her hospitalization for COVID-19-related pneumonia.A 29-year-old woman presented to the emergency department of the First Affiliated Hospital,Zhejiang University School of Medicine with progressive respiratory distress associated with a 2-day history of fever,nausea,and vomiting.The patient was transferred to the intensive care unit(ICU),where she underwent tracheostomy for mechanical ventilation due to her severe clinical condition and very low arterial partial pressure of oxygen.The nasopharyngeal swab test confirmed SARS-CoV-2 infection.Laboratory tests revealed neutrophilic leukocytosis,prolonged prothrombin time,and elevated D-dimer and fibrinogen levels.Left hemiplegia was reported 18 days later during her stay in the ICU after discontinuation of the sedative medications.Central facial palsy on the left side,dysarthria,and facial droop were present,with complete paralysis of the ipsilateral upper and lower limbs.Computed tomography(CT)of the head and magnetic resonance imaging of the brain confirmed the presence of lesions in the right hemisphere affecting the territories of the anterior and middle cerebral arteries,consistent with ischemic stroke.Pulmonary and splenic infarcts were also found after CT of the chest.The age of the patient and the absence of serious concomitant cardiovascular diseases place the emphasis on the capacity of SARS-CoV-2 infection to be an independent cerebrovascular risk factor.Increased levels of D-dimer and positivity forβ2-glycoprotein antibody could confirm the theory of endothelial activation and hypercoagulability,but other mechanisms-still under discussion-should not be excluded.

Cold chain and severe acute respiratory syndrome coronavirus 2 transmission:a review for challenges and coping strategies

Since June 2020,the re-emergence of coronavirus disease 2019(COVID-19)epidemics in parts of China was linked to the cold chain,which attracted extensive attention and heated discussions from the public.According to the typical characteristics of these epidemics,we speculated a possible route of transmission from cold chain to human.A series of factors in the supply chain contributed to the epidemics if the cold chain were contaminated by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),such as temperature,humidity,personal hygiene/protection,and disinfection.The workers who worked in the cold chain at the receiving end faced a higher risk of being infected when they were not well protected.Facing the difficult situation,China put forward targeted and powerful countermeasures to block the cold chain-related risk.However,in the context of the unstable pandemic situation globally,the risk of the cold chain needs to be recognized and evaluated seriously.Hence,in this review,we reviewed the cold chain-related epidemics in China,analyzed the possible mechanisms,introduced the Chinese experience,and suggested coping strategies for the global epidemic prevention and control.

Evolutionary dynamics of the severe acute respiratory syndrome coronavirus 2 genomes

The coronavirus disease 2019(COVID-19)pandemic has caused immense losses in human lives and the global economy and posed significant challenges for global public health.As severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the causative agent of COVID-19,has evolved,thousands of single nucleotide variants(SNVs)have been identified across the viral genome.The roles of individual SNVs in the zoonotic origin,evolution,and transmission of SARS-CoV-2 have become the focus of many studies.This review summarizes recent comparative genomic analyses of SARS-CoV-2 and related coronaviruses(SC2r-CoVs)found in non-human animals,including delineation of SARS-CoV-2 lineages based on characteristic SNVs.We also discuss the current understanding of receptor-binding domain(RBD)evolution and characteristic mutations in variants of concern(VOCs)of SARS-CoV-2,as well as possible co-evolution between RBD and its receptor,angiotensin-converting enzyme 2(ACE2).We propose that the interplay between SARS-CoV-2 and host RNA editing mechanisms might have partially resulted in the bias in nucleotide changes during SARS-CoV-2 evolution.Finally,we outline some current challenges,including difficulty in deciphering the complicated relationship between viral pathogenicity and infectivity of different variants,and monitoring transmission of SARS-CoV-2 between humans and animals as the pandemic progresses.

Expert Recommendation for Novel Severe Acute Respiratory Syndrome Coronavirus 2 Vaccination in HIV-Infected Adults

The outbreak of coronavirus disease 2019(COVID-19)caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has become a pandemic.SARS-CoV-2 vaccination is currently being actively promoted worldwide as a promising measure to combat the pandemic.However,human immunodeficiency virus(HIV)-infected individuals who manifest varying degrees of immunodeficiency and chronic inflammation may require special consideration with regards to vaccine types and the timing of immunization depending on specific clinical situations.The present recommendation provides a reference for SARS-CoV-2 vaccination in HIV-infected patients.

Long, thin transmission chains of Severe Acute Respiratory Syndrome Coronavirus 2 may go undetected for several weeks at low to moderate reproduction numbers: Implications for containment and elimination strategy

Severe Acute Respiratory Syndrome Coronavirus 1(SARS-CoV-1)infections almost always caused overt symptoms,so effective case and contact management enabled its effective eradication within months.However,Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)usually causes only mild symptoms,so transmission chains may grow to include several individuals before at least one index case becomes ill enough to self-report for diagnosis and care.Here,simple mathematical models were developed to evaluate the implications of delayed index case detection for retrospective contact tracing and management responses.Specifically,these simulations illustrate how:(1)Contact tracing and management may effectively contain most but not all large SARS-CoV-2 clusters arising at foci with high reproduction numbers because rapidly expanding transmission chains ensure at least one overtly symptomatic index case occurs within two viral generations a week or less apart.(2)However,lower reproduction numbers give rise to thinner transmission chains extending through longer sequences of non-reporting asymptomatic and paucisymptomatic individuals,often spanning three or more viral generations(2 weeks of transmission)before an overtly symptomatic index case occurs.(3)Consequently,it is not always possible to fully trace and contain such long,thin transmission chains,so the community transmission they give rise to is underrepresented in surveillance data.(4)Wherever surveillance systems are weak and/or transmission proceeds within population groups with lower rates of overt clinical symptoms and/or self-reporting,case and contact management effectiveness may be more severely limited,even at the higher reproduction numbers associated with larger outbreaks.(5)Because passive surveillance platforms may be especially slow to detect the thinner transmission chains that occur at low reproduction numbers,establishing satisfactory confidence of elimination may require that no confirmed cases are detected for two full months,throughout which presumptive preventative measures must be maintained to ensure complete collapse of undetected residual transmission.(6)Greater scope exists for overcoming these limitations by enhancing field surveillance for new suspected cases than by improving diagnostic test sensitivity.(7)While population-wide active surveillance may enable complete traceability and containment,this goal may also be achievable through enhanced passive surveillance for paucisymptomatic infections,combining readily accessible decentralized testing with population hypersensitization to self-reporting with mild symptoms.Containment and elimination of SARS-CoV-2 will rely far more upon presumptive,population-wide prevention measures than was necessary for SARS-CoV-1,necessitating greater ambition,political will,investment,public support,persistence and patience.Nevertheless,case and contact management may be invaluable for at least partially containing SARS-CoV-2 transmission,especially larger outbreaks,but only if enabled by sufficiently sensitive surveillance.Furthermore,consistently complete transmission chain containment may be enabled by focally enhanced surveillance around manageably small numbers of outbreaks in the end stages of successful elimination campaigns,so that their endpoints may be accelerated and sustained.

Pushing past the tipping points in containment trajectories of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)epidemics:A simple arithmetic rationale for crushing the curve instead of merely flattening it

Countries with ambitious national strategies to crush the curve of their Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)epidemic trajectories include China,Korea,Japan,Taiwan,New Zealand and Australia.However,the United States and many hard-hit European countries,like Ireland,Italy,Spain,France and the United Kingdom,currently appear content to merely flatten the curve of their epidemic trajectories so that transmission persists at rates their critical care services can cope with.Here I present a simple set of arithmetic modelling analyses that are accessible to non-specialists and explain why preferable crush the curve strategies,to eliminate transmission within months,would require only a modest amount of additional containment effort relative to the tipping point targeted by flatten the curve strategies,which allow epidemics to persist at supposedly steady,manageable levels for years,decades or even indefinitely.

Severe Acute Respiratory Syndrome Coronavirus 2 Virus-Like Particle and Its Application in Chinese Medical Research

Background:The global outbreak of coronavirus disease 2019(COVID-19)has brought disastrous consequences to public health and medical systems,whereas no approved medications are currently available.Benefits of traditional Chinese medicine(TCM)against COVID-19 have been observed,however,the underlying mechanistic actions remain unclarified.Due to high pathogenicity and infectivity of the new coronavirus(severe acute respiratory syndrome coronavirus 2[SARS-CoV-2]),the lack of access to SARS-CoV-2 and biosafety level 3(P3)facilities has impeded scientific investigations of TCM against COVID-19.Though low-pathogenic coronavirus and pseudoviral systems have been applied to substitute SARS-CoV-2 in fundamental studies,both models cannot imitate virological and clinical features associated with SARS-CoV-2.The virus-like particle(VLP)is a virological model that is safe and could be performed without biosafety protections.Aims and Objectives:To construct VLP of SARS-CoV-2 containing structural proteins of authentic viruses and resembling the morphology,partial life cycle,and immunoreactions of natural virions,and to introduce VLP into Chinese medical research.Materials and Methods:Using mammalian expression system,we have currently constructed SARS-CoV-2 VLP containing four essential structural proteins.Results:Based on this model,we propose six aspects of research that could be carried out for TCM formulas in the fight against COVID-19.Conclusion:Application of the VLP model provides a safe methodology to strengthen the response systems of Chinese medicine in preventing and controlling newly identified infectious diseases and offers collaborative opportunities for interdisciplinary deciphering of molecular and biological basis of anti-viral TCM formulas.

Exploring the potential mechanisms of impairment on genitourinary system associated with coronavirus disease 2019 infection:Bioinformatics and molecular simulation analyses

Objective:The novel coronavirus(severe acute respiratory syndrome coronavirus 2)has been spreading worldwide since December 2019,posing a serious danger to human health and socioeconomic development.A large number of clinical trials have revealed that coronavirus disease 2019(COVID-19)results in multi-organ damage including the urogenital system.This study aimed to explore the potential mechanisms of genitourinary damage associated with COVID-19 infection through bioinformatics and molecular simulation analysis.Methods:We used multiple publicly available databases to explore the expression patterns of angiotensin-converting enzyme 2(ACE2),transmembrane serine protease 2(TMPRSS2),and CD147 in major organs in the healthy and disease-specific populations,particularly the genitourinary organs.Single-cell RNA sequencing was used to analyze the cell-specific expression patterns of ACE2,TMPRSS2,CD147,cytokine receptors,and cytokine interacting proteins in genitourinary organs,such as the bladder,kidney,prostate,and testis.Additionally,gene set enrichmentanalysis was used to investigate the relationship between testosterone levels and COVID-19 vulnerability in patients with prostate cancer.Results:The results revealed that ACE2,TMPRSS2,and CD147 were highly expressed in normal urogenital organs.Then,they were also highly expressed in multiple tumors and chronic kidney diseases.Additionally,ACE2,TMPRSS2,and CD147 were significantly expressed in a range of cells in urogenital organs according to single-cell RNA sequencing.Cytokine receptors and cytokine interacting proteins,especially CCL2,JUN,and TIMP1,were commonly highly expressed in urogenital organs.Finally,gene set enrichment analysis results showed that high testosterone levels in prostate cancer patients were significantly related to the JAK-STAT signaling pathway and the Toll-like receptor signaling pathway which were associated with COVID-19.Conclusion:Our study provides new insights into the potential mechanisms of severe acute respiratory syndrome coronavirus 2 damage to urogenital organs from multiple perspectives,which may draw the attention of urologists to COVID-19 and contribute to the development of targeted drugs.

Traditional Chinese medicine for treatment of coronavirus disease 2019:a review

prevalence.A number of clinical workers and researchers have made great efforts to understand the pathogenesis and clinical characteristics and develop effective drugs for treatment.However,no effective drugs with antiviral effects on severe acute respiratory syndrome coronavirus 2 have been discovered currently.Traditional Chinese medicine(TCM)has gained abundant experience in the treatment of infectious diseases for thousands of years.In this review,the authors summarized the clinical outcome,pathogensis and current application of TCM on coronavirus disease 2019.Further,we discussed the potential mechanisms and the future research directions of TCM against severe acute respiratory syndrome coronavirus 2.

Comparison of Clinical Characteristics and Outcomes of Pediatric and Adult Patients with Coronavirus Disease 2019 in Shenzhen,China

Objective Here we aimed to investigate the difference in clinical characteristics and outcomes between pediatric and adult patients with COVID-19.Methods A total of 333 consecutive patients with laboratory-confirmed SARS-CoV-2 infection treated in the departments of Internal medicine of Shenzhen Third People’s Hospital from January 11 th to February 10 th,2020 were included.The data were obtained from electronic medical records.The epidemiological data,clinical characteristics,length of hospital stays,and outcomes of pediatric and adult patients were compared.Results Compared with adult patients,pediatric patients had a shorter time of symptom onset to hospitalization than adults[median time,1(IQR,1.0-1.0)d vs.3(IQR,2.0-6.0)d,P<0.001],milder or fewer symptoms,less severe chest CT findings.The clinical severity classification of children was less severe than adults.Up to 15 th March,the end of the follow-up,33(100%)children and 292(97.3%)adult patients had been discharged from hospital.Only 2(0.7%)adult patients died,with an overall case mortality of 0.6%.The median length of hospital stay of pediatric patients was shorter than that of adult patients[19(95%CI:16.6-21.4)d vs.21(95%CI:19.9-22.1)d,P=0.024].Conclusion Pediatric patients with COVID-19 had milder or less clinical symptoms,less evident pulmonary imaging changes,better prognosis,and shorter length of hospital stay.

Corticosteroids Treatment of Patients with Coronavirus Disease 2019:A Propensity Score Matching Study

The role of corticosteroids in the treatment of coronavirus disease 2019(COVID-19)is controversial.In the present study,we evaluated the effects of adjuvant corticosteroids treatment on the outcome of patients with COVID-19(n=966),using Propensity Score Matching to adjust for potential differences between the corticosteroids group(n=289)and the non-corticosteroids group(n=677).Analysis of data without adjusting differences in baseline characteristics indicated that the proportion of mechanical ventilation and the mortality was higher in the corticosteroids treatment group in total or severe/critical patients.The duration of viral shedding was longer in the non-corticosteroids treatment group in total or general/mild patients.After adjusting the difference between the corticosteroids and non-corticosteroids treatment group,the analysis revealed that the use of corticosteroids had no effect on the duration of viral shedding,in-hospital mortality or 28-day mortality.

Clinical Features and Organ System Dysfunction in Coronavirus Disease 2019 in China

Objectives: To enhance understanding of COVID-19 in clinical characteristics, related organ system dysfunctions and therapies. Methods: We enrolled patients with COVID-19 admitted to two Chinese hospitals from 19 January 2020 to 15 March 2020 and collected demographic and clinical data. Results: We retrospectively enrolled 130 patients: 7 mild, 103 moderate, and 20 severe cases. Severe patients were older than mild/moderate patients (60.1 vs 52.9 years;P = 0.028) and had more comorbidities (85.0% vs 52.7%;p = 0.006). 116 patients (89.2%) were 2019-noval coronavirus RNA-positive with a median detectable time of 10 days. Obvious absorbed of pneumonia in chest imaging occurred in 20 days. The most common symptoms were fever (n = 87, 66.9%), cough (n = 74, 56.9%), fatigue (n = 73, 56.2%), and chest tightness (n = 54, 41.5%). The incidence of liver, kidney, heart, and coagulation dysfunction was 38.4%, 24.5%, 30.1%, and 24.6%, respectively. The most frequently used antiviral therapies were arbidol (n = 64, 49.2%), oseltamivir (n = 73, 56.2%), and Lianhua Qingwen (n = 73, 56.2%). All patients recovered being hospitalized with a median duration of 15 days. Conclusions: Middle-aged and elderly with comorbidities are more likely to be infected with COVID-19 and develop severe symptoms. The lung, liver, heart, kidney, and coagulation system all may sustain injury, especially in severe cases.

Screening key target genes for coronavirus disease 2019 based on bioinformatics and gene network

Objective:To use bioinformatics and gene networks to screen key target genes of coronavirus disease 2019,which provides references for clinical research and development of drugs for coronavirus disease 2019.Methods:Target genes related to coronavirus disease 2019 were screened in the GeneCards and National Center for Biotechnology Information databases,and the obtained gene data were imported into the Database for Annotation,Visualization and Integrated Discovery(Version 6.8)database to collect the related information about pathways and genes.The genes enriched in the first 20 pathways and the genes whose occurrence frequency≥5 were imported into the String database respectively to construct protein-protein interaction network diagram and compare the two network diagrams.Results:TNF,IL-6,IL-2,IL-8,CXCL8,IL1B,CCL2,IFNG,STAT1,MAPK1,MAPK3,MAPK8,TP53 and RELA are ranked top in the two network diagrams,and the frequency of occurrence in the first 20 pathways was≥5.Conclusion:The incidence of coronavirus disease 2019 is associated with multiple signaling pathways,including influenza A,pathways in cancer,toll-like receptor signaling pathway,hypoxia-inducible factor-1 signaling pathway,et al.TNF,IL-6,IL-2,IL-8,CXCL8,IL1B,CCL2,IFNG,STAT1,MAPK1,MAPK3,MAPK8,TP53 and RELA are closely related to coronavirus disease 2019,which needs to be further studied.By analyzing the pathways of the genes related to coronavirus disease 2019 and the interactive network diagrams between the genes,it is helpful to understand the pathogenesis of the disease and provide a reference for clinical research and development of effective drugs for coronavirus disease 2019.

The protection of CoronaVac against the infection of wild-type SARS-CoV-2(WH-09)or Omicron variant in nude-hACE2 mice

Background:Immunocompromised individuals have an increased risk of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection and severe outcomes,but we pay less attention to these people.Athymic nude mice are a murine strain with a spontaneous deficiency of the Foxn1 gene,which can result in thymic degeneration or its absence,leading to immunosuppression and a decrease in the number of T cells,and are widely used in preclinical evaluations of disease in immunocompromised populations.Methods:We investigated the protection of the coronavirus disease 2019(COVID-19)inactivated vaccine(CoronaVac)against the infection of wild-type SARS-CoV-2(WH-09)or Omicron variant utilizing a hybrid-type nude-hACE2 mouse model.Results:Compared with nude-hACE2/W mice,the viral load in the brain and lung tissue of nude-hACE2 mice(nude-hACE2/WV)infected with WH-09 after vaccination significantly decreased,and the histopathological changes were also reduced.The viral load in the brain and lung tissue of nude-hACE2 mice(nude-hACE2/OV)infected with the Omicron variant after vaccination was lower than that in nude-hACE2/O,but histopathological symptoms did not improve significantly.Conclusion:CoronaVac provides some protection against infection of both WH-09 and the Omicron variant in the nude-hACE2 mice.Our findings aimed to provide a reference for vaccination against SARS-CoV-2 in immunocompromised populations.

Symptomatic COVID-19 in University Students: A School-Wide Web-Based Questionnaire Survey during the Omicron Variant Outbreak

Aim: To detect risk and preventive factors associated with the Omicron variant infection in university students, a combination of a web-based survey and multivariate logistic regression analysis was introduced as the front-line initiatives by the school health practitioners. Design: Questionnaire survey. Methods: The school-wide web-based questionnaire survey was conducted among our university students as a part of the annual health check-up in April, 2023. The positive outcome was confined to the first symptomatic COVID-19 onset during the Omicron variant outbreak. Results: In this self-administered survey, risk or protective associations were merely estimated statistically in university students (n = 5406). In measured factors, karaoke and club/group activities could maintain the statistical significance in adjusted odds ratios (ORs) as relative risk factors, and science course, measles/ rubella (MR) vaccination, and COVID-19 vaccination remained as relative protective factors in adjusted OR analyses. Club/group activities with member gathering and karaoke sing-along sessions in university students may frequently have WHO’s three Cs. These risk factors are still important topics for the infection control of COVID-19 in university students. Together with some recent reports from other researchers, the significant protective role of MR vaccine in our survey warrants further clinical investigation. If the breakthrough infection continuously constitutes the majority of infection, real data in test-negative case-control or web-based questionnaire design continue to be important for statistical analysis to determine the minimal requirement of our strategies which may be equivalent to or replace COVID-19 vaccines.

Impact of vitamin D on COVID-19 and other viral diseases

This editorial aims to elucidate the intricate relationship between vitamin D and viral pathogenesis.It explores the anticipated role of vitamin D as a modulator in the immune response against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and other viral pathogens.The editorial comments are based on the review article by Engin et al.The potential role of vitamin D in modulating immune responses has been highlighted by several studies,suggesting that it may influence both the risk and severity of infections.Vitamin D receptors are present in immunocompetent cells,which indicates that vitamin D can potentially modulate innate and adaptive immune responses.This context is relevant in the pathophysiology of coronavirus disease 2019(COVID-19),where the immune response to the virus can significantly impact the disease progression and outcome.The immunomodulatory effects of vitamin D can protect against SARSCoV-2 infection by enhancing innate and adaptive immune responses.It also maintains the integrity of the body's physical barriers and modulates inflammatory responses,thereby preventing entry and replication of the virus.Many studies have suggested that adequate vitamin D levels help alleviate morbidity and mortality associated with COVID-19.Furthermore,vitamin D supplementation has been linked with a lower risk of severe disease and mortality in COVID-19 patients,particularly in those with a deficiency during seasons with less sunlight exposure.