Build an Agent-Based Model for COVID-19 Effect of Mitigation Policies

Non-Drug Intervention (NDI) is one of the important means to prevent and control the outbreak of coronavirus disease 2019 (COVID-19), and the implementation of this series of measures plays a key role in the development of the epidemic. The purpose of this paper is to study the impact of different mitigation measures on the situation of the COVID 19, and effectively respond to the prevention and control situation in the "post-epidemic era". The present work is based on the Susceptible-Exposed-Infectious-Remove-Susceptible (SEIRS) Model, and adapted the agent-based model (ABM) to construct the epidemic prevention and control model framework to simulate the COVID-19 epidemic from three aspects: social distance, personal protection, and bed resources. The experiment results show that the above NDI are effective mitigation measures for epidemic prevention and control, and can play a positive role in the recurrence of COVID-19, but a single measure cannot prevent the recurrence of infection peaks and curb the spread of the epidemic;When social distance and personal protection rules are out of control, bed resources will become an important guarantee for epidemic prevention and control. Although the spread of the epidemic cannot be curbed, it can slow down the recurrence of the peak of the epidemic;When people abide by social distance and personal protection rules, the pressure on bed resources will be eased. At the same time, under the interaction of the three measures, not only the death toll can be reduced, but the spread of the epidemic can also be effectively curbed. © 2022 ACM.

Nonlinear dynamics modeling and epidemic forecast of COVID-19

To study the spreading trend and risk of COVID-19, according to the characteristics of COVID-19, this paper proposes a new transmission dynamic model named SLIR(susceptible-low-risk-infected-recovered), based on the classic SIR model by considering government control and personal protection measures. The equilibria, stability and bifurcation of the model are analyzed to reveal the propagation mechanism of COVID-19. In order to improve the prediction accuracy of the model, the least square method is employed to estimate the model parameters based on the real data of COVID-19 in the United States. Finally, the model is used to predict and analyze COVID-19 in the United States. The simulation results show that compared with the traditional SIR model, this model can better predict the spreading trend of COVID-19 in the United States, and the actual official data has further verified its effectiveness. The proposed model can effectively simulate the spreading of COVID-19 and help governments choose appropriate prevention and control measures. Copyright ©2023 Control and Decision.

Preparation and Properties of an Efficient Purification Material for Personal Protection

At present, the filtration of virus and other small particles in the air by meltblown cloth produced by electret treatment mainly depends on its electrostatic adsorption mechanism. However, because the surface charge of melt blown fabric can not be maintained for a long time, it can not maintain high efficiency filtration for a long time. Therefore, there is no guarantee for the medical staffs to not be infected by COVID-19. Therefore, it is necessary to improve the mechanical filtration efficiency of melt blown fabric in the situation of an electric charge loss. In this paper, nylon 6 (PA6) nanofibers were electrospun on melt blown cloth by electrospinning technology, and a sandwich material with melt blown cloth as surface layer and PA6 nanofibers as middle layer was made by hot- pressing technology;the surface morphology, thermal and mechanical properties of the sandwich material were characterized, and its filtration performance was tested. The experimental results show that the surface integrity of the sandwich material is high, and the diameter of nanofibers can reach about 67 nm;without the electret treatment, the filtration efficiency of the sandwich material for particles in an size of 0.2 μm is more than 95%,while the filtration efficiency of non-woven fabric is zero;the filtration resistance of the material is about 284 Pa, which is suitable for personal protection. © 2023 Chengdu University of Science and Technology. All rights reserved.

Bacteria Filtration Efficiency for Different Types of Protective Face Masks

Emerging infectious diseases that we are witnessing in the modern age are among the leading public health concerns. They most often occur in the form of epidemics or pandemics, and they have not been sufficiently researched. Owing to the current coronavirus disease 2019 (COVID-19) pandemic, the World Health Organization has published various recommendations to prevent the spread of this communicable disease, including a recommendation to wear protective facial masks. Therefore, this study aimed to determine the filtration effectiveness of bacteria, yeasts, and molds on three different commonly and commercially available masks used in children's educational institutions. In addition, the bacterial content of indoor air bioaerosols was identified. The genera Staphylococcus and Micrococcus were dominant in all samples, whereas bacteria of the genera Bacillus, Acinetobacter, and Corynebacterium were identified at a significantly smaller number. Bacterial, yeast, and mold filtering effectiveness increased from the single-layer cloth mask, which proved to be the least effective, to the surgical mask, to the filtering facepiece type 2 (FFP2) mask. Furthermore, surveys are needed to study the effectiveness of protective measures.

Indications for Intubation in COVID-19

Intubation and invasive mechanical ventilation are often unavoidable in most severe cases of COVID-19 pneumonia;however, deciding the optimum timing and best practices of intubation is challenging. The decision to proceed with intubation should be based on an integrated patient evaluation and not limited to the assessment of the severity of hypoxemia alone. Intubation is a maneuver exposing the operator to a high risk of contamination, therefore adequate personal protection equipment is mandatory. Benefits of intubation over noninvasive respiratory support include reduction or suppression of the respiratory drive, reduction of the basal metabolism and allowance of maintaining protective mechanical ventilation. On the other hand, risks are related to the need for sedation, the presence of an artificial airway and exposure to mechanical ventilation, which may result in overlapping ventilator-associated bacterial pneumonia and ventilator-induced lung injury. Balancing between risks and benefits of intubation in this context is challenging and the optimum timing of intubation remains largely an open question. This chapter discusses the clinical, technical, and safety aspects that deserve to be considered when considering intubation in patients with severe COVID-19-related acute respiratory failure. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.

Inactivation of Pathogenic Microorganisms on Polymeric Materials through Ozonation

Ozone-based technologies have been evaluated to inactivate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on surfaces. However, the vast diversity of information makes it difficult to establish common ground for determining the best practices for using this technology. The objective of this work is to evaluate the success of N95 mask decontamination by ozonation, determining the specific parameters for process control. To quantify the effectiveness of the process, a disinfection protocol was initially developed based on two bacterial species (Escherichia coli and Staphylococcus pseudintermedius), followed by another disinfection assay using the murine hepatitis coronavirus (MHV-3), in a laboratory-scale prototype. Ozone is an effective candidate for use against SARS-CoV-2 or other viruses to disinfect personal protection equipment (PPE). © 2023 Wiley-VCH GmbH.

Factors Affecting the Acceptance of Personal Protection Measures among Patients before Having Covid-19

Background and Aim: The most recent threat to the global community is the ongoing outbreak of the disease known as Coronavirus Disease 2019 (COVID-19). Taking personal protection measures (PPM) is crucial to prevent the spread of COVID-19. This study aimed to determine the factors affecting the acceptance of PPM among patients before having COVID-19 admitted to hospitals in northwestern of Iran. Materials and Methods: In this cross-sectional study, 560 eligible patients with a diagnosis of COVID-19 were selected by convenience sampling. Data were collected from January 6 to May 21, 2021, through a researcher-made questionnaire and were analyzed with descriptive statistics (number, percentage, mean, standard deviation), independent t-test, and multiple linear regression by SPSS. A significance level of 5% was selected. Results: The average age of the participants was 60.1 (16.01) years with an age range of 21 to 95 years. Most of the participants were male (53.9%) and married (91.8%). The mean score of PPM acceptance among patients was 16.55 (2.59) out of 20 points. Multiple linear regression analysis determined employment status (β=0.29, P<0.001), residency (β=-0.19, P<0.001), education level (β=0.11, P=0.048), smoking (β=-0.10, P=0.03) and income level (β=0.13, P=0.01), as predictors of acceptance of PPM. Other personal and occupational variables, including age, gender, marriage, living status, having children, and history of influenza vaccination, were not found to be effective in predicting the acceptance of personal protection measures among participating patients. Conclusion: The acceptance of personal protection measures among patients was relatively high. Acceptance of the unemployed, rural residents, illiterate, smokers, and those with low-income level was low. This study emphasizes the need to pay attention to the changes in the individual, social and economic characteristics of the community and their effects on preventive health behaviors, especially in vulnerable groups. © 2022 the Authors. Published by Tehran University of Medical Sciences.

Image Processing and Deep Neural Networks for Face Mask Detection

The proper use of a mask is crucial for lowering COVID 19 and transmission. According to the research, transmission is completely decreased when the mask is used appropriately. Factors like sunlight and several items can affect how appropriatel y applied face masks are classified and detected. Cotton masks, sponge masks, scarves, and other options greatly lessen the effect of personal protection in such circumstances. The research suggests a novel modified formula for classifying masks into three categories—a proper mask, a no mask, and an erroneous mask—using deep learning and machine learning. First, we provide a brand-new face mask classification and detection algorithm that combines deep learning, the viola Jones method, and Efficient-Yolov3 Wearing a mask, not wearing a mask, or wearing the wrong mask are the three options. On the dataset with or without mask pictures, the suggested system outperforms and is more accurate when compared to existing techniques. The results of experiments and analysis are also based on the classification knowledge set. In comparison to the present methodology's categorization accuracy of 84%, the anticipated formula boosted it to 97%. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

SARS-CoV-2: Outline, Prevention, and Decontamination.

The new coronavirus began to spread around the world in late 2019. Initially, it was found only in China, but in the following days there were reported cases of infections in other countries. Subsequently, based on taxonomy, phylogeny, and accepted practice, the virus was officially designated as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As a result of the rapid spread of SARS-CoV-2 in different countries around the world, on March 11, 2020, the World Health Organization (WHO) announced a status change in the disease caused by this coronavirus-from an epidemic to a pandemic disease. Although the world is taking unprecedented efforts to control the spread of SARS-CoV-2, the number of confirmed cases is rising. Therefore, effective preventive measures are needed in order to limit the spread of illness. The prevention measures are mainly based on information on the virus transmission routes, its environmental stability, and persistence on commonly touched surfaces. Social distancing, mask usage, and good hygiene practice are the most important recommendations for general public. Healthcare professionals who are directly involved in SARS-CoV-2 patients care are more exposed to virus infection and additional protection measures are necessary, including protective suits, aprons, face shields, goggles, and gloves. Due to the stability of SARS-CoV-2 on different surfaces, such as glass, paper, or wood, proper disinfection is crucial. Several studies have shown that despite the virus's stability, it is sensitive to various disinfectants, such as ethanol, isopropanol, sodium hypochlorite, or hydrogen peroxide. These findings underline the importance of having comprehensive knowledge about SARS-CoV-2 and multidirectional strategies in order to limit the spread of the virus. This review is a summary of the most important information about SARS-CoV-2, such as its stability on different surfaces, protection strategies, and decontamination options.

Resilience in healthcare supply chains: a review of the UK's response to the COVID19 pandemic

PurposeThe purpose of this explorative research is to analyse the resilience of the United Kingdom's (UK) healthcare supply chains from a customer's perspective in the light of the coronavirus pandemic.Design/methodology/approachUsing the capabilities of preparedness, robustness, recovery and adaptability as the foundational percept for supply chain resilience, 22 healthcare professionals in 17 of the UK's National Health Scheme (NHS) Trusts were interviewed to explore their personal and organisational approaches adopted relative to the provision of eye protection, gloves, gowns, aprons, masks and respirators. The Dynamic Capabilities View is mapped to the resilience capabilities and used to analyse the data from a transformational supply chain research perspective.FindingsThe supply chains were largely unprepared, which was not particularly surprising even though the availability of gloves was significantly better compared to the other personal protective equipment (PPE). Techniques adopted to ensure robustness and recovery revealed the use of unsanctioned methods such as extended use of PPE beyond recommended use, redefinition of guidelines, protocols and procedures by infection control and the use of expired PPE – all of which compromised customer well-being.Research limitations/implicationsAs the paper views resilience through the lens of customers, it does not provide the perspectives of the supply chain practitioners as to the reasons for the findings and the challenges within these supply chains.Practical implicationsThe compromise of the well-being of healthcare workers due to the vulnerabilities of healthcare supply chains is highlighted to managers and prescriptions for post-disruption adaptability are made.Originality/valueThis paper introduces transformative research to supply chain resilience research by uniquely looking at resilience from the customers' well-being perspective.

Determination of the Morphological Characteristics of Eight Types of Protective Face Masks and Respirators

Respiratory infections have arisen as a public health concern. The regulation of COVID-19 is based on knowledge of its transmission mechanism. Masks and respirators act as a physical barrier against respiratory droplets that enter through the nose and mouth, as well as droplets spat by sick persons. Textile masks (including 'do-it-yourself'), surgical (medical) masks and respirators are the three basic types of personal protection devices, covering the human face. The purpose of our work is to give a study on the morphological features of masks and respirators, which are widely accessible in Bulgarian shops and pharmacies, revealing their structure and differences between them. The results will be further used for the assessment of heat and mass transfer abilities of the masks/respirators, which are largely preconditioned by the masks' morphology. © 2022 IEEE.

Improved face mask testing system

A new way to measure the penetration efficiency of a face mask is introduced. It has a number of advantages over the currently used measurement systems in which a stationary mask is impacted with a moving aerosol during which the upstream and downstream particle concentrations are compared. The equivalent system described here instead moves a mask through a stationary aerosol in a closed chamber and compares the particle concentrations before and after the movement of the mask. This system provides many advantages, such as greater simplicity, greater accuracy, an exact constant aerosol flow speed through a mask, more easily made concentration measurements, more realistic impacts, more controlled averaging, the absence of the need for preliminary impacts during flow stabilization, and a lower cost. A laboratory prototype of the system has been fabricated and seen to perform as expected. Data obtained from this prototype are displayed, analyzed, and used to demonstrate the consistency and repeatability of the system. A portable fully-automated compact prototype has also been designed and fabricated. This device can be easily operated, and the total time required to test a mask, from material insertion to result display, is only a few minutes.

Dentists Perception to Personal Protection Equipment Use during the COVID-19 Pandemic (Analytical Study)

Background: It has been demonstrated that the use of personal protective equipment (PPE) by health care workers, including dentists, reduces the transmission of COVID-19. PPE lowers patient morbidity and death as well as illness and absenteeism. Aim: The purpose of the study was to evaluate the impact of dentists' perceptions of personal infection control and their level of trust in PPE as part of the dental profession's response to the COVID-19 pandemic. Materials and Method: The sample size was (388) participants distributed as specialist, general dental practitioners, dental branch practitioners, and rotators. Google form prepared with specific questions;demographical and knowledge questions translated to the mother language (Arabic Language). Structured and distributed online by sharing the link through electronic platforms. Two responses were used in a statistical analysis using the SPSS version (SPSS Package version (21). Significant p value of 0.05 or less was used. Descriptive statistics were used in the data analysis to analyze the percentage, and mean values. All questions employ the spearman test to determine correlations. Kruskal-Wallis for comparing differences between groups including qualification and experience period between participants. Result: Significant results were shown in both rotators and general practitioners for comparison of different qualification levels between dentists. All dentists had good knowledge regarding the PPE. Conclusions: Overall, dentists in the current study had good knowledge of the PPE used for COVID-19 protection. However, it was discovered that knowledge is important for rotators and general practitioners in the majority of the PPE questions. © 2022, Ain Shams University Faculty of Medicine. All rights reserved.

In the COVID-19 Pandemic Situation Effect of Youths Emotional Factors on School Maladjustment

The purpose of this study is to verify the mediating effect of individual factors and friend factors in the process of influencing youths' emotional factors on school maladjustment in the COVID-19 pandemic situation. To this end, a survey was conducted on 495 youths living in South Korea. The data were analyzed with SPSS 22.0 and PROCESS macro ver. 3.5 programs. The research results were derived as follows. First, it was found that there was a significant correlation between emotional risk factors, school maladjustment, personal protection factors, and friend protection factors of adolescents. Second, emotional risk factors, personal protection factors, and friend protection. Phosphorus was found to have a significant effect on school maladjustment. Third, it was found that personal protection factors and friend protection factors were multi-mediated in the process of adolescents' emotional risk affecting school maladjustment. Through these research results, the significance and limitations of this study were presented, and discussions for subsequent studies were presented © 2022 IEEE.

High class filtering facepiece (FFP) are fundamental and effective in protection of emergency health care workers: an observational cohort study in a German community.

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a highly contagious airborne virus inducing pandemic coronavirus disease 2019 (COVID-19). This is most relevant for medical staff working under harmful conditions in emergencies often dealing with patients and an undefined SARS-CoV-2 status. We aimed to measure the effect of high-class filtering facepieces (FFP) in emergency medical service (EMS) staff by analyzing seroprevalence and history of positive polymerase chain reaction (PCR) for SARS-CoV-2. METHOD: This observational cohort study included workers in EMS, who were compared with hospital staff (HS) and staff, which was not directly involved in patient care (NPC). All direct patient contacts of EMS workers were protected by FFP2/N95 (filtering face piece protection class 2/non-oil-based particulates filter efficiency 95%) masks, whereas HS was protected by FFP2/N95 exclusively when a patient had a proven or suspected SARS-CoV-2 infection. NPC was not protected by higher FFP. The seroprevalence of SARS-CoV-2 antibodies was analyzed by immunoassay by end of 12/2020 together with the history of a positive PCR. In addition, a self-assessment was performed regarding the quantity of SARS-CoV-2 positive contacts, about flu symptoms and personal belief of previous COVID-19 infections. RESULTS: The period in which contact to SARS-CoV-2 positive patients has been possible was 10 months (March to December 2020)-with 54,681 patient contacts documented for EMS-either emergencies (n = 33,241) or transportation services (n = 21,440). Seven hundred-thirty (n = 730) participants were included into the study (n = EMS: 325, HS: 322 and NPC: 83). The analysis of the survey showed that the exposure to patients with an unknown and consecutive positive SARS-CoV-2 result was significantly higher for EMS when compared to HS (EMS 55% vs. HS 30%, p = 0.01). The incidence of a SARS-CoV-2 infection in our cohort was 1.2% (EMS), 2.2% (HS) and 2.4% (NPC) within the three groups (ns) and lowest in EMS. Furthermore, the belief of previous COVID-19 was significant higher in EMS (19% vs. 10%), CONCLUSION: The consistent use of FFP2/N95 in EMS is able to prevent work-related SARS-CoV-2 infections in emergency situations. The significance of physical airway protection in exposed medical staff is still relevant especially under the aspect of new viral variants and unclear effectiveness of new vaccines.

Study on airway assessment practices for elective procedures during pre-anesthetic evaluation in COVID-19 pandemic- A national online survey (SAFE PAC Survey).

Background and Aims: A pilot study among anesthesiologists, revealed a wide variation among individual practices including skipping pre-anesthetic airway assessment during COVID-19 pandemic because of the fear of getting infected. Risk of infection during pre-anesthetic airway assessment has not been studied. The primary objective of the survey was to evaluate the practices of airway examination by anesthesiologists during this pandemic period. Secondary objectives were to study the effects of institutional factors and other individual practices on risk modification and the incidence of COVID-19 infection among anesthesiologists. Material and Methods: A survey was conducted using a pre-validated questionnaire comprising of 35 questions. The questionnaire was circulated among 4676 members of the Indian Society of Anaesthesiologists (ISA) through Google Forms by email. Results: Of the 4676 members contacted via email, 470 were returned undelivered. From the remaining 4206 questionnaire recipients, 456 completed responses were obtained giving a response rate of 10.8%. Percentage, mean and standard deviation were calculated using EZR software. The conduct of pre-anesthetic airway assessment has decreased by 31.7% during the pandemic, leading to 5.2% of participants encountering unanticipated difficult airway. Among the respondents, eight percent were infected. Conclusion: Avoidance of preoperative airway assessment by anesthesiologists during the COVID-19 pandemic has led to rising unanticipated difficult airway undermining the patient safety. Adherence to recommended practices ensures safety from risk of COVID-19 infection.

Efficacy of facemasks in mitigating respiratory exposure to submicron aerosols.

We designed a novel experimental set-up to pseudo-simultaneously measure size-segregated filtration efficiency (ηF), breathing resistance (ηP) and potential usage time (tB) for 11 types of face protective equipment (FPE; four respirators; three medical; and four handmade) in the submicron range. As expected, the highest ηF was exhibited by respirators (97 ± 3%), followed by medical (81 ± 7%) and handmade (47 ± 13%). Similarly, the breathing resistance was highest for respirators, followed by medical and handmade FPE. Combined analysis of efficiency and breathing resistance highlighted trade-offs, i.e. respirators showing the best overall performance across these two indicators, followed by medical and handmade FPE. This hierarchy was also confirmed by quality factor, which is a performance indicator of filters. Detailed assessment of size-segregated aerosols, combined with the scanning electron microscope imaging, revealed material characteristics such as pore density, fiber thickness, filter material and number of layers influence their performance. ηF and ηP showed an inverse exponential decay with time. Using their cross-over point, in combination with acceptable breathability, allowed to estimate tB as 3.2-9.5 h (respirators), 2.6-7.3 h (medical masks) and 4.0-8.8 h (handmade). While relatively longer tB of handmade FPE indicate breathing comfort, they are far less efficient in filtering virus-laden submicron aerosols compared with respirators.

Continuous Disinfection of Airborne Pathogens Using Far UV-C KRCL∗Microplasma Lamp for Personal Protection

Microplasma lamps based on the confinement of a weakly-ionized, low-temperature plasma in a microscale cavity have been found to be ideal for far UV-C radiation at 222 nm (KrCl ∗ excimer). During the last several years, researchers have demonstrated that far UV-C 222 nm efficiently kills airborne pathogens (coronaviruses) with minimal risk of harm to human skin or eyes. Therefore, the data support the premise that far UV-C 222 nm from a KrCl∗ excimer emission in the microplasma flat lamp can be used safely in occupied spaces. In particular, ACGIH recently increased the allowed human exposure levels at 222 nm more than seven times. 1 © 2022 IEEE.

Resilience in healthcare supply chains: a review of the UK’s response to the COVID19 pandemic

Purpose: The purpose of this explorative research is to analyse the resilience of the United Kingdom's (UK) healthcare supply chains from a customer’s perspective in the light of the coronavirus pandemic. Design/methodology/approach: Using the capabilities of preparedness, robustness, recovery and adaptability as the foundational percept for supply chain resilience, 22 healthcare professionals in 17 of the UK's National Health Scheme (NHS) Trusts were interviewed to explore their personal and organisational approaches adopted relative to the provision of eye protection, gloves, gowns, aprons, masks and respirators. The Dynamic Capabilities View is mapped to the resilience capabilities and used to analyse the data from a transformational supply chain research perspective. Findings: The supply chains were largely unprepared, which was not particularly surprising even though the availability of gloves was significantly better compared to the other personal protective equipment (PPE). Techniques adopted to ensure robustness and recovery revealed the use of unsanctioned methods such as extended use of PPE beyond recommended use, redefinition of guidelines, protocols and procedures by infection control and the use of expired PPE – all of which compromised customer well-being. Research limitations/implications: As the paper views resilience through the lens of customers, it does not provide the perspectives of the supply chain practitioners as to the reasons for the findings and the challenges within these supply chains. Practical implications: The compromise of the well-being of healthcare workers due to the vulnerabilities of healthcare supply chains is highlighted to managers and prescriptions for post-disruption adaptability are made. Originality/value: This paper introduces transformative research to supply chain resilience research by uniquely looking at resilience from the customers' well-being perspective. © 2022, Emerald Publishing Limited.