COVID

21 pages, 4798 KiB

Open AccessArticle

Development and Validation of a Methodology to Measure Exhaled Carbon Dioxide (CO₂) and Control Indoor Air Renewal

by Marta Baselga, Juan J. Alba and Alberto J. Schuhmacher

COVID 2023, 3(12), 1797-1817; https://doi.org/10.3390/covid3120124 - 18 Dec 2023

Viewed by 1388

The measurement of carbon dioxide (CO₂) has emerged as a cost-effective and straightforward technique for indirectly managing indoor air quality, aiding in the reduction of the potentially pathogen-laden aerosol concentrations to which we are exposed. Unfortunately, inadequate practices often limit the [...] Read more.

The measurement of carbon dioxide (CO₂) has emerged as a cost-effective and straightforward technique for indirectly managing indoor air quality, aiding in the reduction of the potentially pathogen-laden aerosol concentrations to which we are exposed. Unfortunately, inadequate practices often limit the interpretation of CO₂ levels and neglect methodologies that ensure proper air renewal. This study presents a novel methodology for measuring and controlling indoor CO₂ levels in shared spaces, comprising four stages: analysis, diagnosis, correction protocols, and monitoring/control/surveillance (MCS). This methodology underwent validation in practical settings, including a cultural center (representing spaces with uniform activities) and 40 commercial spaces (with diverse activities) in Zaragoza, Spain. The results indicate the feasibility of swiftly implementing measures to enhance shared air renewal, with the immediate opening of doors and windows being the most direct solution. The proposed methodology is practical and has the potential to mitigate the risk of the aerosol transmission of respiratory diseases. Consequently, we anticipate that this work will contribute to establishing methodological foundations for CO₂ measurement as a valuable, standardized, and reliable tool. Full article

(This article belongs to the Special Issue Airborne Transmission of Diseases in Outdoors and Indoors)

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16 pages, 8185 KiB

Open AccessArticle

Analytical Solution of the Susceptible-Infected-Recovered/Removed Model for the Not-Too-Late Temporal Evolution of Epidemics for General Time-Dependent Recovery and Infection Rates

by Reinhard Schlickeiser and Martin Kröger

COVID 2023, 3(12), 1781-1796; https://doi.org/10.3390/covid3120123 - 16 Dec 2023

Cited by 1 | Viewed by 1172

Abstract

The dynamical equations of the susceptible-infected-recovered/removed (SIR) epidemics model play an important role in predicting and/or analyzing the temporal evolution of epidemic outbreaks. Crucial input quantities are the time-dependent infection (

a (t)

) and recovery (

μ (t)

[...] Read more.

The dynamical equations of the susceptible-infected-recovered/removed (SIR) epidemics model play an important role in predicting and/or analyzing the temporal evolution of epidemic outbreaks. Crucial input quantities are the time-dependent infection (

a (t)

) and recovery (

μ (t)

) rates regulating the transitions between the compartments

S \to I

and

I \to R

, respectively. Accurate analytical approximations for the temporal dependence of the rate of new infections

\overset{˚}{J} (t) = a (t) S (t) I (t)

and the corresponding cumulative fraction of new infections

J (t) = J (t_{0}) + \int_{t_{0}}^{t} d x \overset{˚}{J} (x)

are available in the literature for either stationary infection and recovery rates or for a stationary value of the ratio

k (t) = μ (t) / a (t)

. Here, a new and original accurate analytical approximation is derived for general, arbitrary, and different temporal dependencies of the infection and recovery rates, which is valid for not-too-late times after the start of the infection when the cumulative fraction

J (t) ≪ 1

is much less than unity. The comparison of the analytical approximation with the exact numerical solution of the SIR equations for different illustrative examples proves the accuracy of the analytical approach. Full article

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20 pages, 912 KiB

Open AccessArticle

Analyzing County-Level COVID-19 Vaccination Rates in Texas: A New Lindley Regression Model

by Nicollas S. S. da Costa, Maria do Carmo S. de Lima and Gauss M. Cordeiro

COVID 2023, 3(12), 1761-1780; https://doi.org/10.3390/covid3120122 - 4 Dec 2023

Cited by 1 | Viewed by 1488

Abstract

This work aims to study the factors that explain the COVID-19 vaccination rate through a generalized odd log-logistic Lindley regression model with a shape systematic component. To accomplish this, a dataset of the vaccination rate of 254 counties in the state of Texas, [...] Read more.

This work aims to study the factors that explain the COVID-19 vaccination rate through a generalized odd log-logistic Lindley regression model with a shape systematic component. To accomplish this, a dataset of the vaccination rate of 254 counties in the state of Texas, US, was used, and simulations were performed to investigate the accuracy of the maximum likelihood estimators in the proposed regression model. The mathematical properties investigated provide important information about the characteristics of the distribution. Diagnostic analysis and deviance residuals are addressed to examine the fit of the model. The proposed model shows effectiveness in identifying the key variables of COVID-19 vaccination rates at the county level, which can contribute to improving vaccination campaigns. Moreover, the findings corroborate with prior studies, and the new distribution is a suitable alternative model for future works on different datasets. Full article

(This article belongs to the Special Issue Analysis of Modeling and Statistics for COVID-19)

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15 pages, 971 KiB

Open AccessReview

The Two Sides of the COVID-19 Pandemic

by Ravinder Kumar, Vartika Srivastava and Kripa N. Nand

COVID 2023, 3(12), 1746-1760; https://doi.org/10.3390/covid3120121 - 4 Dec 2023

Cited by 4 | Viewed by 4217

Abstract

On 5 May 2023, the World Health Organization (WHO) officially declared the end of the coronavirus disease-19 (or COVID-19) pandemic. Even before the official announcement from the WHO, signs of recovery from the pandemic started appearing, especially after rapid worldwide vaccination. As society [...] Read more.

On 5 May 2023, the World Health Organization (WHO) officially declared the end of the coronavirus disease-19 (or COVID-19) pandemic. Even before the official announcement from the WHO, signs of recovery from the pandemic started appearing, especially after rapid worldwide vaccination. As society is getting back to its usual with each passing day, with the increasing socio-economic activities, discussion of the negative and positive outcomes of the COVID-19 pandemic remain the predominant topic of debate. Through this review, we discuss the bright side of the pandemic without undermining the pain and suffering everyone has gone through in this pandemic. The review also examined the painful side of the pandemic. Therefore, this review can be looked at as a comparison between this pandemic’s positive and negative effects. The review discussed aspects ranging from technological development, including mRNA-based vaccines, artificial intelligence-based screening, and telemedicine, to social behavior, from individual to global and from health to the environment. The review also examined the areas needing more attention for managing future pandemics. The review also highlighted what should be followed or continued for our preparedness for any possible pandemic. Toward the end, we also discussed how this pandemic has better prepared the world for future pandemics, as predicted by experts. Full article

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13 pages, 2337 KiB

Open AccessArticle

Incorporating Virtual Problem-Based Learning in Instrumental Chemistry during the COVID-19 Pandemic

by Xiaoping Li, Ying Guo, Simon M. Mwongela and Michael Kirberger

COVID 2023, 3(12), 1733-1745; https://doi.org/10.3390/covid3120120 - 29 Nov 2023

Viewed by 1444

Abstract

The COVID-19 pandemic has presented substantial challenges to higher education, leading to economic loss and disruptions in STEM courses. This study addresses these issues through the successful implementation of a problem-based learning research project within the Instrumental Chemistry course at Georgia Gwinnett College [...] Read more.

The COVID-19 pandemic has presented substantial challenges to higher education, leading to economic loss and disruptions in STEM courses. This study addresses these issues through the successful implementation of a problem-based learning research project within the Instrumental Chemistry course at Georgia Gwinnett College (GGC). Focused on instrumental chemistry, the project spans various categories, requiring students to propose solutions to real-case scenarios using specific analytical instruments. Despite the shift to a hybrid teaching modality, students exhibited commendable preparation and investigation skills, as demonstrated by their projects. Assessment data, including a student survey and written report evaluations, underscore significant skill improvements in literature survey, instrument selection, experimental design, and data analysis. This problem-based learning approach not only mitigated the disruptions caused by the pandemic but also fostered enhanced capabilities and motivation among students. The study’s findings contribute insights into the adaptability and effectiveness of problem-based learning in analytical chemistry education within a hybrid teaching framework, offering valuable considerations for future educational strategies in STEM disciplines and beyond. Full article

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12 pages, 1031 KiB

Open AccessArticle

Eating Habits and Mental Health of College Students in Japan during the COVID-19 Pandemic

by Tomoko Imoto, Yuichiro Hoshino, Yoshiyuki Sato, Yusuke Ohsaki and Hitoshi Shirakawa

COVID 2023, 3(12), 1721-1732; https://doi.org/10.3390/covid3120119 - 26 Nov 2023

Viewed by 1894

Abstract

While the relationship between eating habits and mental health has been widely studied, there is limited research focusing on college students during emergency situations such as pandemics. We conducted an online questionnaire survey to address this gap. Clustering analysis was applied to identify [...] Read more.

While the relationship between eating habits and mental health has been widely studied, there is limited research focusing on college students during emergency situations such as pandemics. We conducted an online questionnaire survey to address this gap. Clustering analysis was applied to identify students’ eating habits, which are possibly more complex than traditional eating habits. Based on the identified eating habits, the students were separated into five groups. We evaluated the relationship between eating habits and mental health in these five groups using University Personality Inventory scores. Based on the results, the largest group—corresponding to slightly less than half of the participants—had the highest vegetable intake and mental health levels. This aligns with findings from numerous prior studies. However, our novel discovery was the presence of another group within those with higher vegetable intake, who had lower levels of mental health. Conversely, a group with lower vegetable intake had higher levels of mental health; remarkably, students in this group frequently consumed soft drinks, suggesting that, during the COVID-19 emergency, indulgent food and drinks may have played a role in enhancing mental health. Full article

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14 pages, 1760 KiB

Open AccessArticle

Does COVID-19 Really Exacerbate Urticaria? A Survey of 166 Patients in China

by Qian Yang, Zihao Zou, Wei Cao, Yunzhou Shi, Xianjun Xiao, Sijue Chen and Ying Li

COVID 2023, 3(12), 1707-1720; https://doi.org/10.3390/covid3120118 - 21 Nov 2023

Viewed by 2455

Abstract

The COVID-19 pandemic significantly disrupted global healthcare systems. The impacts of SARS-CoV-2 infection on urticaria and its management are unknown. This study aimed to collect information about patients with urticaria infected with SARS-CoV-2 and to investigate the impact of SARS-CoV-2 infection on urticaria [...] Read more.

The COVID-19 pandemic significantly disrupted global healthcare systems. The impacts of SARS-CoV-2 infection on urticaria and its management are unknown. This study aimed to collect information about patients with urticaria infected with SARS-CoV-2 and to investigate the impact of SARS-CoV-2 infection on urticaria severity, course, and treatment to better support recovery. This was a questionnaire-based study of patients with urticaria infected with SARS-CoV-2. Changes in urticaria severity (measured with the urticaria activity score (UAS)), course, and treatment were assessed before, during, and after SARS-CoV-2 infection. The mean (±SD) UAS scores were 5.17 ± 1.67, 4.23 ± 1.98, and 4.37 ± 1.93 before, during, and after SARS-CoV-2 infection, respectively (F = 8.839, p < 0.01). The median (IQR) wheal score was 0.464 (0.464, 0.763), 0.464 (0.138, 0.763), and 0.464 (0.138, 0.763) before, during, and after infection, respectively (Kruskal–Wallis H-test, H = 12.230, p = 0.02). The median (IQR) pruritus score was 0.695 (0.395, 0.695), 0.394 (0.123, 0.695), and 0.394 (0.123, 0.695) before, during, and after infection, respectively (Kruskal–Wallis H-test, H = 21.001, p < 0.01). Within the limitations of a questionnaire study, urticaria appears to improve during SARS-CoV-2 infection and worsens slightly after recovery, and the frequency of Western medicine use increases. Full article

(This article belongs to the Special Issue Immune Responses in Coronavirus Disease)

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COVID, Volume 3, Issue 12 (December 2023) – 7 articles

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