Sars-Related Corona Viruses-A Challenge

SARS (Severe acute respiratory syndrome)-related corona viruses was first of all discovered 18 years ago in china from bats. Previously some study shown that bats are infected to animal kingdom and from animal this virus spread in human. As per report of identification and characterization of novel corona virus which is responsible for epidemic of acute respiratory syndrome in human beings. First of all this protein of novel SARS are seen in Wuhan city of, China in January 2020.Copyright © 2019, Advanced Scientific Research. All rights reserved.

COVID-19 Infection in Hemodialysis Patients, Incidence, Risk Factors and Mortality. Single Centre Study

Background: Hemodialysis patients are not only prone to acquire COVID-19 infection but also more likely to suffer a higher rate of morbidity and mortality. This study aims to report the incidence and mortality rate of COVID-19 infection in our hemodialysis patients and to determine risk factors. Methods: This is an observational, retrospective study conducted in the dialysis unit of Dubai Hospital. Our target population was hemodialysis patients who tested positive for COVID infection (PCR assay of the nasopharyngeal swab) from 1st April 2020 to 31st August 2021. Our primary outcome was to study the mortality rate associated with COVID-19 infection in dialysis patients in Dubai hospital. Our secondary objectives were to study the incidence and determine risk factors for the severity of infection. Patient demographics and clinical features were collected from medical record software, i.e., EPIC. Univariate Cox regression analysis was performed to evaluate potential risk factors for mortality in our cohort. Results: 72 out of 250 (28.8%) hemodialysis patients acquired COVID infection during the study period, the median age was 54.32 (15-93) years, and 56.94% (n=41) were male. The most common comorbid was hypertension (59.72%), while the main symptom at presentation was shortness of breath (25%). One-third of patients required a different form of oxygen therapy, and 11.11% of patients were mechanically ventilated. The mortality rate was 16.6%. High median age, ischemic heart disease, low absolute lymphocyte count, and high levels of ferritin, LDH, and procalcitonin, as well as mechanical ventilation, were statistically significant risk factors associated with mortality. Conclusion: The overall outcome of COVID infection in our hemodialysis patients was better compared to the hemodialysis population from other parts of the world. © 2022 Ram et al.

A Prospective Approach on Covid-19 Forecasting Using LSTM

The novel Corona virus has been proclaimed as a worldwide pandemic through World Health Organization in the March 2020 has immensely affected the world with its ferocity. By observation, the scientists got to know that it transmits from one human to other by droplets which range from larger respiratory droplets to smaller aerosols or direct contact with an infected person. Its impurity has been assessed to have an incubation time of 6.4 days than a simple reproduction amount of 2.24-3.58.[19] The transmission rate and spread of infection is quite rapid as compared to other fatal viral infections encountered till date. A massive loss of human life was faced even by the developed countries which had the best health-care facilities. According to WHO, COVID-19 has been confirmed in 238,521,855 people over the world, with 4,863,818 deaths as of October 9th, 2021. After experiencing the second covid wave, the number of cases had got dropped drastically but the increase in their number in the recent days is a major cause of concern. This stresses us to build some prediction models which could help in providing relief to the virus-prone areas. In this study, we are using time series for predicting forthcoming cases of corona virus. © 2022 IEEE.

2019-NCoV: What every neurologist should know?

The 2019 novel Corona Virus pandemic beginning from Wuhan, China primarily affects the respiratory tract but its has impacted clinical practice across a range of specialities including neurology. We review the bearing of the 2019 NCoV infection on neurological practice. Neurological manifestations are less common than respiratory manifestations, yet conspicuous, affecting nearly over a third of hospitalized individuals. These may be classified in to early – headache, dizziness, hyposmia and hypogeusia and late – encephalopathy. Rarely but surely, a very small proportion of infected individuals might present with stroke. Certain neurological conditions, including cerebrovascular disease in both China and Italy and dementia in Italy predispose to infection and more severe manifestations, requiring intensive care unit admission. There is no convincing evidence that the manifestations, course and outcome of various neurological disorders is impacted by 2019 nCoV infection. Concerns of an increased risk of febrile seizures offset by a reduced frequency of infection in the paediatric age group. Individuals with multiple sclerosis might potentially experience both true and pseudorelapses. Besides a direct effect, 2019 nCoV has tremendously affected neurological care by disrupting the continuity of care and the availability of neurological medicines worldwide. Neurologists should respond to this challenge by developing and sustaining innovative methods of providing care as well as alerting the society at large to adopt measures to contain the spread of 2019 nCoV.

The Outbreak of Novel Coronavirus-a New Type of Threat in 2020: Genesis, Detection, Treatment, and Management

Background: COVID-19 is a new, health-threatening infectious disease in the world in 2020 and is caused by a novel coronavirus SARS-CoV-2. As of July 13, 2020, 4,881,579 active cases of COVID-19 were diagnosed, and 571,080 deaths were reported globally. In India, 301,850 active cases and 23,187 deaths were reported. To date, no effective treatment is available against the deadly virus SARS-CoV-2. Drug manufacturers, institutional laboratories, and other organizations have started developing vaccines to combat COVID-19 infection. Method(s): Science Direct, Elsevier, PubMed, Scopus, and Nature databases were referred to know the current scenario of the disease. Moreover, recent data have been obtained from the World Health Orga-nization, Centre of Disease Control, case studies, newspapers, and Worldometer reports. Data of Vaccine Centre at the London School of Hygiene & Tropical Medicine, Clinicaltrials.gov, and US National Library of Medicine have also been accessed to obtain the latest information about ongoing clinical tri-als. Result(s): The primary source of the SARS-CoV-2 outbreak is connected to the Hunan seafood and live animal market in Wuhan city, Hubei Province, China. Like;SARS-CoV, and MERS-CoV, SARS-CoV-2 is also a zoonotic virus affecting the lower respiratory tract in humans. The pathogenesis of COVID-19 involves attachment of its Spike (S) protein to the angiotensin-converting enzyme 2 (ACE2) receptor in the lower respiratory tract in humans. The most common symptoms of COVID-19 are fever, cough, sore throat, fatigue, headache, myalgia, septic shock, and breathlessness. Few patients with COVID-19 infection experience diarrhea, vomiting, and abdominal pain. Currently, FDA approved drugs being used to treat COVID-19. Conclusion(s): This review article presents the importance of traditional Indian herbs recommended by AYUSH as precautionary and curative measures of COVID-19 until vaccines and drugs are made avail-able. Moreover, this article discussed the origin, symptoms, mode of transmission, management, and diagnostics techniques for the detection of the SARS-CoV-2 virus.Copyright © 2021 Bentham Science Publishers.

Post-COVID-19 Syndrome Clinical Manifestations: A Systematic Review.

BACKGROUND: Coronavirus disease-2019 (COVID-19) is a global pandemic health problem that causes a wide spectrum of clinical manifestations and considerable mortality rates. Unfortunately, recovered patients who survive COVID-19 may continue to report a wide variety of clinical manifestations of multisystem affection such as pulmonary embolism, deep vein thrombosis, acute myocardial infarction, depression, anxiety, myalgia, dyspnea, and fatigue. OBJECTIVE: We aimed to summarize the current literature regarding the prevalence of post-COVID- 19 manifestations. METHODS: We conducted a systematic review of post-COVID-19 manifestations by searching MEDLINE via PubMed, Scopus, Web of Science (WOS), EBSCO, Wily, and World health organization (WHO) databases. Screening, study selection, data extraction, data synthesis, and quality assessment were made by two independent reviewers. RESULTS: Of 1,371 references, 817 references remained after removing duplicates. Reviews, case reports, commentaries, and any article containing non-original information were excluded. According to the eligibility criteria for this systematic review, 12 studies were included for qualitative synthesis. The overall prevalence of post-COVID-19 manifestations ranged from 35% to 90.5%. Fatigue, dyspnea, neuropsychological disorders, and pain were the most frequent post-COVID-19 symptoms. CONCLUSION: This systematic review showed that 35% to 90.5% of recovered patients who survive COVID-19 continue to have a wide variety of clinical manifestations, including fatigue, dyspnea, neuropsychological disorders, and pain as the most frequent post-COVID-19 symptoms.

A network pharmacology approach to explore the mechanism of action of Yiqi Fumai lyophilized injection in the treatment of novel coronavirus disease

Background: Shengmai decoction, which has been included in the diagnosis and treatment of coronavirus disease 2019 (COVID-19), is effective in the early treatment of patients with severe COVID-19. Yiqi Fumai lyophilized injection (YQFM) is a modern Chinese medicine preparation of the Shengmai decoction. The mechanism of its intervention at the molecular level in the severe stage of COVID-19 remains unclear. Therefore, it is necessary to investigate the mechanism of YQFM in the treatment of patients with severe COVID-19. Methods: The corresponding target genes of the main active ingredients in YQFM and COVID-19 were obtained by using multiple databases and literature retrieval. A protein-protein interaction network was constructed, and enrichment analysis of the target was performed using Cytoscape 3.8.1. Lastly, the docking of all the identified compounds with angiotensin-converting enzyme II was confirmed by applying molecular docking technology. Results: YQFM has anti-inflammatory effects on RAW267.4 macrophages. The main active compounds of YQFM are all effective anti-inflammatory agents, and these active compounds also show beneficial physiological functions, such as anti-oxidation, anti-bacterial, and anticancer activities. Gene Ontology analysis showed enrichment in the following pathways: lipopolysaccharides, interleukins, NF-kappa B, interleukin-2 and others, revealing that YQFM may play a role in the treatment of patients with severe COVID-19 through these pathways. Conclusion: YQFM has multicomponent and multitarget characteristics, and it could reduce lung injury by inhibiting inflammatory reactions, promoting antiviral activities, and regulating immunity, among other functions, to treat patients with severe COVID-19.

Results of thrombectomy in lower-extremity ischemia in patients with COVID-19 and respiratory failure of different severity

Aim. To analyze the results of thrombectomy in lower-extremity ischemia in patients with coronavirus disease 2019 (COVID-19) and respiratory failure of different severity. Material and methods. This retrospective, cohort, comparative study for the period from May 1, 2020 to March 1, 2022 included 305 patients with acute lower-extremity ischemia and COVID-19. Depending on the type of oxygen support, three groups of patients were formed: group 1 (n=168) - nasal oxygen insufflation;group 2 (n=92) - non-invasive ventilation (NIV);group 3 (n=45) - artificial ventilation (AV). Thrombectomy was carried out according to the standard technique using Fogarty catheters (3F-6F - depending on the vessel size). After the diagnosis was established before and after the start of surgical treatment, all patients received the following therapy: Unfractionated IV heparin infusion at an initial rate of 1000 U/r, adjusted to maintain the activated partial thromboplastin time at 2-3 times the normal value;2. Oral acetylsalicylic acid 125 mg;3. Analgesics. Results. Myocardial infarction and ischemic stroke were not detected in the total sample. The highest number of deaths (group 1: 5,3%, n=9;group 2: 72,8%, n=67;group 3: 100%, n=45;p<0,0001), retrombosis (group 1: 18,4%, n=31;group 2: 69,5%, n=64;group 3: 91,1%, n=41;p<0,0001) and limb amputations (group 1: 9,5%, n=16;group 2: 56,5%, n=52;group 3: 91,1%, n=41;p<0,0001) was recorded in group 3 patients. Conclusion. In patients receiving mechanical ventilation, COVID-19 have more aggressive course, which is expressed in an increase in laboratory para-meters (C-reactive protein, ferritin, interleukin-6, D-dimer), the severity of pneumonia and location of thrombosis in the tibial arteries. Among patients with COVID-19 receiving mechanical ventilation, the greatest number of re-thromboses (91,1%), limb amputations (91,1%), and deaths (100%) are noted, which suggests the expediency of abandoning open thrombectomy in favor of anticoagulant/antiplatelet therapy in this cohort of patients. The development of arterial thrombosis in patients with COVID-19 receiving mechanical ventilation is an indicator of a high risk of death. Open thrombectomy in combination with anticoagulant/antiplatelet therapy is most effective in patients on nasal oxygen insufflation or NIV. Copyright © 2022, Silicea-Poligraf. All rights reserved.

Progress in research on human coronavirus and relevant vaccines

Coronaviruses (CoVs) are positive-sense and single-strand RNA viruses which have an extensive range of natural hosts and cause respiratory, gastrointestinal, hepatic, renal and neurological diseases of varying severities in livestock, birds and humans.Seven human coronaviruses (HCoVs) have been discovered, of which severe acute respiratory syndrome coronavirus (SAKSCoV), Middle East respiratory snydrome coronavirus (MERSCoV) and 2019 novel coronavirus (2019-nCov) may cause severe fatal pneumonia and have posed a global threat to public health.This paper reviews the progress in research on pathogenicity and vaccines of HCoV. Copyright © 2022 Changchun Institute of Biological Products. All rights reserved.

Latest progress and prospect of development of COVID-19 vaccine

The emerging Corona virus Disease 2019 (COVID-19) pandemic poses a massive crisis to global public health. World Health Organization (WHO) declared the global pandemic of COVID-19 on March 11, 2020. The progress of 2019- nCoV vaccines cover nearly all forms of current vaccine research, including inactivated vaccine, recombinant protein vaccine, viral vector-based vaccine, nucleic-acid vaccine and live attenuated vaccine, as well as the vaccine design based on novel concepts such as reverse vaccinology and vaccinomics. This article reviews the COVID-19 vaccines in development and clinical trials as well as the challenge in vaccine development. Copyright © 2021 Changchun Institute of Biological Products. All rights reserved.

YouTube: Is It a Reliable Source of Nutrition Information on COVID-19 Pandemic?

Data on the nutrition-related misinformation about COVID-19 are limited. This study analysed the quality and accuracy of the nutrition information available on YouTube about current COVID-19 pandemic as well as assessed the content of the videos. YouTube was searched using the terms "nutrition and COVID-19" in Turkish on 1 February 2021. Videos were filtered according to relevancy, and the first 280 videos were analysed. A total of 218 videos were reviewed and classified as "misleading" or "relevant" depending on the information provided. The transparency, utility, reliability, and accuracy of video contents were assessed. The videos attracted a cumulative 6,258,694 views. There were 178 (81.7%) fully relevant and 40 (18.3%) misleading videos. Approximately 80% of the videos shared by health professionals were relevant videos. Government organisations only shared relevant videos. Relevant videos had higher reliability, accuracy, and quality than misleading videos. The nutrition-related content of COVID-19 videos is suboptimal on YouTube. As the COVID-19 pandemic worsens, and nutrition could improve immunity, health professionals and educational and government organisations need to engage more in the spread of nutrition-related COVID-19 information to Internet platforms based on nutrition guidelines and the latest scientific evidence. This will be a practical and immediately implementable public health strategy to effectively spread the right information.

Monitoring Novel Corona Virus using Machine Learning

In this article, we are working on a new Pandemic Corona (COVID-19) virus. COVID-19 is an infectious disease that causes serious lung damage. COVID-19 causes a disease in humans and has killed many people around the world. However, the virus has been declared pandemic by the World Health Organization (WHO) and all countries are trying to control and block all locations. In particular, four standard forecasting models have been used: linear regression (LR), logistics regression (LOR) and polynomial regression. Many areas of application that require the identification and hierarchy of threats have long used automatic learning models. [1] Machine-based (ML) analysis methods have been shown to be useful in predicting preoperative outcomes and improving decision-making about future actions. Different forecasting methods are widely used to solve forecasting problems. The purpose of this study was to determine the function of COVID-19 research and machine learning applications and algorithms for various purposes [2]. © 2022 IEEE.

COVID-19: In persons’ view

Through the survey conducted by the researchers, it can be inferred that COVID-19 pandemic followed by complete lockdown in India had its immense impact on peoples ‘economic and employment conditions. In India, a developing country, people strive hard to earn for their living where every basic need is expensive for most of the population, which ultimately resulted in people realising the fact that after lockdown is over they have to work double hard and have to start from the beginning to bring back stability in their life. From difficult times to COVID-19 pandemic, people took refuge in their religion which gave them calmness and also somewhere helped them to visualize their condition in better way without freaking out about their future. © 2022 International Journal of Health Sciences.

A Comparative Study on Bacterial Co-Infections and Prevalence of Multidrug Resistant Organisms among Patients in COVID and Non-COVID Intensive Care Units.

Introduction: Secondary bacterial infections have been reported in majority of patients hospitalized with coronavirus disease 2019 (COVID-19). A study of the antimicrobial susceptibility profiles of these bacterial strains revealed that they were multidrug resistant, demonstrating their resistance to at least three classes of antimicrobial agents including beta-lactams, fluoroquinolones and aminoglycosides. Bacterial co-infection remains as an important cause for high mortality in patients hospitalized with COVID-19. Methods: In our study, we conducted a retrospective comparative analysis of bacterial co-infections and the antimicrobial resistance profile of bacterial isolates obtained from inpatients admitted in COVID-19 and non-COVID-19 intensive care units. The goal was to obtain the etiology and antimicrobial resistance of these infections for more accurate use of antimicrobials in clinical settings. This study involved a total of 648 samples collected from 356 COVID-19 positive patients and 292 COVID-19 negative patients admitted in the intensive care unit over a period of six months from May to October 2020. Results: Among the co-infections found, maximum antimicrobial resistance was found in Acinetobacter species followed by Klebsiella species in both the ICU's. Incidence of bacterial co-infection was found to be higher in COVID-19 intensive care patients and most of these isolates were multidrug resistant strains. Conclusion: Therefore, it is important that co-infections should not be underestimated and instead be made part of an integrated plan to limit the global burden of morbidity and mortality during the SARS-CoV-2 pandemic and beyond.

Convolutional neural network based CT scan classification method for COVID-19 test validation.

Given the novel corona virus discovered in Wuhan, China, in December 2019, due to the high false-negative rate of RT-PCR and the time-consuming to obtain the results, research has proved that computed tomography (CT) has become an auxiliary One of the essential means of diagnosis and treatment of new corona virus pneumonia. Since few COVID-19 CT datasets are currently available, it is proposed to use conditional generative adversarial networks to enhance data to obtain CT datasets with more samples to reduce the risk of over fitting. In addition, a BIN residual block-based method is proposed. The improved U-Net network is used for image segmentation and then combined with multi-layer perception for classification prediction. By comparing with network models such as AlexNet and GoogleNet, it is concluded that the proposed BUF-Net network model has the best performance, reaching an accuracy rate of 93%. Using Grad-CAM technology to visualize the system's output can more intuitively illustrate the critical role of CT images in diagnosing COVID-19. Applying deep learning using the proposed techniques suggested by the above study in medical imaging can help radiologists achieve more effective diagnoses that is the main objective of the research. On the basis of the foregoing, this study proposes to employ CGAN technology to augment the restricted data set, integrate the residual block into the U-Net network, and combine multi-layer perception in order to construct new network architecture for COVID-19 detection using CT images. -19. Given the scarcity of COVID-19 CT datasets, it is proposed that conditional generative adversarial networks be used to augment data in order to obtain CT datasets with more samples and therefore lower the danger of overfitting.

An Experimental Approach to Diagnose Covid-19 Using Optimized CNN

The outburst of novel corona viruses aggregated worldwide and has undergone severe trials to manage medical sector all over the world. A radiologist uses x-rays and Computed Tomography (CT) scans to analyze images through which the existence of corona virus is found. Therefore, imaging and visualization systems contribute a dominant part in diagnosing process and thereby assist the medical experts to take necessary precautions and to overcome these rigorous conditions. In this research, a Multi-Objective Black Widow Optimization based Convolutional Neural Network (MBWO-CNN) method is proposed to diagnose and classify covid-19 data. The proposed method comprises of four stages, preprocess the covid-19 data, attribute selection, tune parameters, and classify cov-id-19 data. Initially, images are fed to preprocess and features are selected using Convolutional Neural Network (CNN). Next, Multi-objective Black Widow Optimization (MBWO) method is imparted to finely tune the hyper parameters of CNN. Lastly, Extreme Learning Machine Auto Encoder (ELM-AE) is used to check the existence of corona virus and further classification is done to classify the covid-19 data into respective classes. The suggested MBWO-CNN model was evaluated for effectiveness by undergoing experiments and the outcomes attained were matched with the outcome stationed by prevailing methods. The outcomes confirmed the astonishing results of the ELM-AE model to classify cov-id-19 data by achieving maximum accuracy of 97.53%. The efficacy of the proposed method is validated and observed that it has yielded outstanding outcomes and is best suitable to diagnose and classify covid-19 data. © 2022, Tech Science Press. All rights reserved.

COVID-19 And Diabetes Mellitus: A Systematic Review On The Recent Situation

BACKGROUND: COVID-19 (corona virus) is a recently acknowledged disease. Corona is spreading quickly in the whole world At least 185 countries. Many cases from china. Covid-19 causes many death and abnormalities. mortality rate in covid-19 patient is low(1.4-2.3) but in diabetic patients have poor immune system and this a severe co-morbidity so mortality rate is high in Diabetic patients with covid-19. Diabetes mellitus refer as risk factor that arises with mortality and severity of covid-19 there's no absolute article and journals to direct the actual connection between diabetes mellitus and covid-19. So the aim of this study to sum up the confirmation About covid-19 and diabetes mellitus breakout all over a meta-analysis and systematic review. METHODS: A writing analysis was applied within detail of SCOPUS PUBMED, DIRECT SCIENCE, & SCIENCE related network. Monitoring analysis, studies of case- series and case reports on the diabetes mellitus in covid-19, were involved. RESULT: Some studies recommended such there are no notable differences in symptoms between diabetes mellitus with covid-19 and non-diabetic corona patients. In this patient acute Respiratory distress syndrome prognosis is poor. Death chances increase with age and seriousness of disease. Those people survive ARS. Some recover completely, while other Encounter lasting Damage of Lungs. Serious Manifestations and rate of death is higher between patients of diabetes mellitus and covid-19. In short this recommended the patient who suffering from diabetes or will be treated with H C Q antibiotics, anti- viral drugs. CONCLUSION: The analysis and the data of this study Convey such determinant condition of diabetes mellitus, which shows the high rate of mortality and severity among the patient who are suffering from covid-19 this article also provide us guidelines and criteria regarding diagnosis that can be convenient in the treatment and prevention of medical condition of the patient who is suffering from diabetes mellitus and covid-19. © The Electrochemical Society

Comparative analysis of Covid- 19 Data: A statistical approach for unraveling the relation between the awareness and healthcare system from Indian perspective

The Novel Corona virus disease caused by SARS-Cov-2 has been declared pandemic by WHO as it unanimously effected almost all the provinces over the globe. It has incapacitated poorer nations as well as paralyzed the healthcare system of world's major economies like Europe and America. Several regulations and measures were put into place to control the spread of the virus and Statistical models been deduced for evaluating the infections in real time. In the present research, Python 3 and kaggle has been applied for data analysis of the dataset retrieved from the various Indian states. An attempt has been made to draw a conclusive relation between the healthcare systems and the awareness as regard to covid infections. There was positive and high co-relation (>0.95) values for total confirmed cases -discharged and first - second dose of vaccinations. A positive and high co relation value of 0.78 was obtained when plotted for total covid tests performed against vaccination while a negative co relation of value -0.117 obtained when percentage covid positive amongst the sample tested was plotted against the total covid test performed. This statistical analysis aid in understanding overall healthcare system of a state and immunity amongst Indian population © 2022 IEEE.

Diagnostic Efficacy of COVID-19 Rapid Antigen Detection Card in Diagnosis of SARS-CoV-2.

Introduction The rapid surge of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) cases globally makes it essential for rapid diagnosis of coronavirus disease 2019 (COVID-19). Real-time reverse-transcription polymerase chain reaction (rtRT-PCR) remains as the gold standard to detect COVID-19 cases because of its greater sensitivity and specificity. However, because of its prolonged turnaround time and technical expertise, recommendations have been made to employ the use of rapid diagnostic test for rapid diagnosis and to curb the spread of the disease. Methods This prospective study was performed in a tertiary COVID-19 care hospital located amidst the semi-urban settings. Both nasopharyngeal and throat swabs collected from the COVID 19 suspected study participants were subjected to both COVID 19 rtRT-PCR and rapid antigen testing. Results Of the total 599 samples tested by rtRT-PCR, 310 (52%) were positive and 289 (48%) tested negative for SARS-CoV-2. Of the 599 samples tested by rapid antigen test (RAT), 230 (38%) were positive and 369 (62%) were negative. The overall sensitivity and specificity of our study kit was found to be 74.19 and 100%, respectively. The sensitivity of the RAT greatly overlaps with the viral load which is determined by the cycle threshold (CT) values of SARS-CoV-2, E gene, and RdRp gene. Conclusion RAT yields rapid results within a short-turnaround time and found to be cost effective. Therefore, this test can be adopted in areas with rapid surge in SARS-CoV-2 cases which can help to rapidly identify the positive cases and to implement isolation and infection control measures.

Assessment of COVID-19 risk and prevention effectiveness among spectators of mass gathering events.

There is a need to evaluate and minimize the risk of novel coronavirus infections at mass gathering events, such as sports. In particular, to consider how to hold mass gathering events, it is important to clarify how the local infection prevalence, the number of spectators, the capacity proportion, and the implementation of preventions affect the infection risk. In this study, we used an environmental exposure model to analyze the relationship between infection risk and infection prevalence, the number of spectators, and the capacity proportion at mass gathering events in football and baseball games. In addition to assessing risk reduction through the implementation of various preventive measures, we assessed how face-mask-wearing proportion affects infection risk. Furthermore, the model was applied to estimate the number of infectors who entered the stadium and the number of newly infected individuals, and to compare them with actual reported cases. The model analysis revealed an 86-95% reduction in the infection risk due to the implementation of face-mask wearing and hand washing. Under conditions in which vaccine effectiveness was 20% and 80%, the risk reduction rates of infection among vaccinated spectators were 36% and 96%, respectively. Among the individual measures, face-mask wearing was particularly effective, and the infection risk increased as the face-mask-wearing proportion decreased. A linear relationship was observed between infection risk at mass gathering events and the infection prevalence. Furthermore, the number of newly infected individuals was also dependent on the number of spectators and the capacity proportion independent of the infection prevalence, confirming the importance of considering spectator capacity in infection risk management. These results highlight that it is beneficial for organisers to ensure prevention compliance and to mitigate or limit the number of spectators according to the prevalence of local infection. Both the estimated and reported numbers of newly infected individuals after the events were small, below 10 per 3-4 million spectators, despite a small gap between these numbers.