COVID, Volume 2, Issue 12 (December 2022) – 13 articles

At the end of 2019, COVID-19 outbreaks occurred one after another in countries worldwide. Managing the outbreak efficiently and stably is an essential public health issue facing countries worldwide. In this paper, based on the SEIR model, we propose a SCEIR model that incorporates close contacts (C) and self-protectors (P). Firstly, the epidemic data of China, the USA, and Italy are predicted and compared with the actual data. Secondly, sensitivity analysis of each parameter in the SCEIR model was conducted using Anylogic. The study shows that the SCEIR model established in this paper has a certain validity. The infection rate in contact with E (𝛽) etc., has positive effects on the basic regeneration number (R₀); the self-isolation rate (φ) etc., has a negative effect on the basic regeneration number (R₀). Emergency management measures are proposed according to the influencing factors corresponding to the model parameters. These can provide theoretical guidance for developing effective epidemic prevention and control measures in areas where the epidemic has not yet been controlled. It also provides some reference for formulating prevention and control policies for similar epidemics that may occur in the future. Full article

COVID-19 represents the greatest health crisis in recent human history. To date, it is still difficult to estimate its impact on mortality. This paper investigates the excess crude mortality in 27 European countries. The differences between the values observed in 2020 and 2021 with those predicted by a joinpoint regression model were evaluated. A multi-regression analysis was implemented to assess the relationship between health variables and excess mortality. Europe experienced a marked and surprising (S-value > 52) increase in crude mortality during 2020 (Δ_% = +10.0%, 95% CI: [2.5; 18.7]) and 2021 (Δ_% = +12.1%, 95% CI: [4.3; 21.2]). The difference between average excesses of Eastern and Western countries was not surprising (S < 2) and had little relevance (Δ_E-W = −2.4, 95% CI: [−2; 7]) during 2020 but was more pronounced (S = 15, Δ_E-W = +17.2, 95% CI: [11.0; 23.5]) during 2021. Excess crude mortality increased in 2021 (Δ_% = +65%, 95% CI: [12.6; 118], S = 5.9). Evidence has been found for a surprising and marked negative linear relationship between COVID-19 vaccinations and excess mortality (“2021 excess mortality = A + BX₄”, with “A = 58 ± 7, S = 28” and “B = −0.65 ± 0.10, S = 22, R_adj² = 0.65, 95% CI: [0.38; 0.82]). In light of the current literature, these findings provide solid evidence of the substantial role of COVID-19 in the unexpected and marked excess mortality recorded in Europe. COVID-19 vaccinations have appeared to be one of the main determinants for reducing mortality. Future research should explore these aspects in more detail. Full article

São Paulo state has been the epicenter of the Coronavirus Disease 2019 (COVID-19) in Brazil, ranking first by state with over six million reported cases. In February 2021, the P.4 lineage was reported in 21 cities across the state by public health authorities due to the L452R mutation. Here, by analyzing 17,304 genome sequences of SARS-CoV-2 sampled between February and August of 2021 in 476 distinct cities in São Paulo, we assess the transmission dynamics of the P.4 lineage and other SARS-CoV-2 variants that were, at the time of the study, co-circulating in the state. Additionally, clinical parameters from the city of Araras, São Paulo (N = 251) were considered to estimate the potential risk and mortality rate associated with the P.4 lineage since its higher prevalence was observed in that city. Our data suggest a low frequency (0.55%) of the P.4 lineage across the state, with the gamma variant being the dominant form in all regions (90%) at that time. Furthermore, no evidence of increased transmissibility and disease severity related to the P.4 lineage was observed. The displacement through the time of different lineages in São Paulo highlights how challenging genomic surveillance appears to track the emergence of new SARS-CoV-2 lineages, which could better guide the implementation of control measures. Full article

Background: Remdesivir is a broad-spectrum antiviral that has been approved as promising medicine worldwide for the fatal pandemic COVID-19 disease. There is a debate over its efficacy, with different studies taking into account a variety of factors. Therefore, we conducted this study to evaluate the primary composite outcome of mortality rate, need for mechanical ventilation (MV), and escalation of care among Remdesivir (RDV) and non-Remdesivir (NoRDV) groups. Methods: Patients with moderate and severe PCR-confirmed COVID-19 infection were observed retrospectively, before and after including RDV in the treatment protocol during the period from August 2020 to February 2021. Result: From the 509 hospitalized patients, 35% received Remdesivir, with 64% being severe patients. The median age in both groups was 59 years old, and there was no significant difference between the two groups regarding gender, baseline characteristics, and comorbidities. In contrast, the median hospital length of stay in the RDV group was lower (8 days) than the NoRDV (9 days), p = 0.004. The composite outcome was 17.7% in the RDV group and 22.2% in the NoRDV group, but the difference was statistically insignificant (p-value 0.289). Adjusted logistic regression demonstrated a non-significant lower association of the composite outcome with RDV use (OR 0.623, 95CI% 0.37–1.02), and a significant reduction occurred in patients <60 years old (OR 0.39, 95%CI 0.17–0.83). However, survival analysis for mortality, MV, and transfer to a higher level revealed insignificant differences in the median time between groups. Subgroup analyses showed that RDV utilization had a non-significant effect on the risk of all three outcomes across different groups. Conclusion: Despite controlling all patient characteristics, treatment with RDV did not improve patient outcomes over other antivirals and standard care. There is an urgent need for further studies to investigate and evaluate new therapeutic approaches or combinations. Full article

Background: The presence and level of anti-SARS-CoV-2 antibodies in PLWH from the Lower Silesia region in Poland. Material and Methods: A total of 216 serum samples of both sexes, aged 21–77, and treated with TDF or TAF together with FTC and INSTI at two points of time. Anyone who did not experience COVID-19 symptoms. Samples were checked for the presence and levels of anti-SARS-CoV-2 antibodies regarding CD4 + T and CD8 + T cells counts, the ratio of these cells, age, sex, VL, and type of tenofovir used. Results: The average level and prevalence of anti-SARS-CoV-2 antibodies during the first wave were 65.81 IU/mL and 4.17%, while during the second wave, they were 125.98 IU/mL and 14.29%, respectively. There was a significant correlation between the number and type of lymphocytes and the presence of anti-SARS-CoV-2 antibodies. We did not find the same correlation regarding anti-SARS-CoV-2 levels. The average level of antibodies was higher during the second wave. There was no difference between the type of tenofovir used and the humoral response, as well as no correlation of anti-SARS-CoV-2 levels with age, gender, or VL. Conclusion: PLWH can have asymptomatic SARS-CoV-2 infection, which can influence the presence, but not levels, of anti-SARS-CoV-2 Ab. No correlation with type of tenofovir was observed. Full article

Multiple vaccines were developed and administered to immunize people worldwide against SARS-CoV-2 infection. However, changes in platelet count following the course of vaccination have been reported by many studies, suggesting vaccine-induced thrombocytopenia. In this context, designing an effective targeted subunit vaccine with high specificity and efficiency for people with low platelet counts has become a challenge for researchers. Using the in silico-based approaches and methods, the present study explored the antigenic epitopes of the spike protein of SARS-CoV-2 involved in initial binding of the virus with the angiotensin converting enzyme-2 receptor (ACE-2) on the respiratory epithelial cells. The top ten major histocompatibility complex-I (MHC-I) and MHC-II restricted epitopes were found to have 95.26% and 99.99% HLA-class-I population coverage, respectively. Among the top ten promiscuous MHC-I restricted epitopes, ’FTISVTTEI’ had the highest global HLA population coverage of 53.24%, with an antigenic score of 0.85 and a docking score of −162.4 Kcal/mol. The epitope ‘KLNDLCFTNV’ had the best antigenic score of 2.69 and an HLA population coverage of 43.4% globally. The study predicted and documented the most suitable epitopes with the widest global HLA coverage for synthesis of an efficient peptide-based vaccine against the deadly COVID-19. Full article

Six months following the national launch of COVID-19 vaccinations in Cameroon, only 1.1% of the target population was fully vaccinated, with women representing less than one-third of the vaccinated population regardless of age, profession, or comorbidities. Hence, the aim of this study was to understand the low COVID-19 vaccination rate of women in order to enhance vaccine uptake. A cross-sectional study was conducted between July and October 2021 through an online survey. Additionally, a retrospective analysis of the Cameroon Ministry of Public Health (MINSANTE) database of the pandemic (COVID-19) for the period of March 2020 to October 2021 was simultaneously carried out. Our sample consisted of 249 responders aged between 18 and 50 years enrolled in the 10 regions of Cameroon, with 142 (57%) who were female. We assessed factors related to having been vaccinated against COVID-19 and predictors of COVID-19 vaccination among non-vaccinated people. Concerning COVID-19 vaccination, 39.2% were not vaccinated. Non-vaccination was statistically associated with being female, being a healthcare worker, fear of adverse effects, and not believing in the vaccine. In the qualitative analysis, women identified themselves as being anti-COVID-19-vaccine for several reasons, including doubts about the quality or safety of the vaccine; the perception that COVID-19 vaccines are presented as being an obligation; and regarding the multitude of vaccines on the market, the belief that there are “more local” effective alternatives to the vaccine. The implementation of the gender approach to COVID-19 vaccination is one factor influencing its effectiveness and sustainability. Full article

Pneumomediastinum, pneumothorax, and subcutaneous emphysema may occur as rare complications of COVID-19. They are associated with worsened prognosis and survival from SARS-CoV-2 pneumonia. The treatment of pneumomediastinum involves supportive care and management of underlying diseases. Our case presents a female patient suffering from COVID-19 pneumonia with life-threatening mediastinal emphysema. According to guidelines, literature, and other clinical sources, no further therapy options were recommended, and survival was improbable. During an interdisciplinary case discussion, we decided to establish a mediastinal drain and tracheal cannula. This achieved a significant reduction of emphysema as well as an improvement in the patient’s clinical condition and long-term survival. This case demonstrates a rarely used invasive therapy for pneumomediastinum. Furthermore, it demonstrates the importance of cooperation with other centers, interdisciplinary teamwork, and of presenting case reviews—especially when guidelines are unavailable. Full article

The strategy of relying solely on current SARS-CoV-2 vaccines to halt SARS-CoV-2 transmission has proven infeasible. In response, many public-health authorities have advocated for using vaccines to limit mortality while permitting unchecked SARS-CoV-2 spread (“learning to live with the disease”). The feasibility of this strategy critically depends on the infection fatality rate (IFR) of SARS-CoV-2. An expectation exists that the IFR will decrease due to selection against virulence. In this work, we perform a viral fitness estimation to examine the basis for this expectation. Our findings suggest large increases in virulence for SARS-CoV-2 would result in minimal loss of transmissibility, implying that the IFR may vary freely under neutral evolutionary drift. We use an SEIRS model framework to examine the effect of hypothetical changes in the IFR on steady-state death tolls under COVID-19 endemicity. Our modeling suggests that endemic SARS-CoV-2 implies vast transmission resulting in yearly US COVID-19 death tolls numbering in the hundreds of thousands under many plausible scenarios, with even modest increases in the IFR leading to unsustainable mortality burdens. Our findings highlight the importance of enacting a concerted strategy and continued development of biomedical interventions to suppress SARS-CoV-2 transmission and slow its evolution. Full article

The declaration of the coronavirus disease 2019 (COVID-19) pandemic led to the enforcement of national lockdowns in several countries. While lockdowns are generally effective in containing the spread of infectious diseases, they are associated with negative impacts on livelihoods. Although evidence suggests that urban informal sector populations in low-resource settings bore the brunt of the adverse economic effects of COVID-19 lockdowns, there is little on how they survived. The article provides insights into the survival mechanisms of urban informal sector populations during a COVID-19 lockdown. Data are from narrative interviews with 30 residents of Kampala City and surrounding areas. We found that the COVID-19 lockdown chiefly jeopardized the livelihoods of urban residents through job loss and reduced incomes. Affected individuals and households primarily survived by making improvisations such as adjusting expenditures and reconfiguring their livelihoods. The cardinal elements of the informal sector, such as limited regulation, served as both a facilitator and constraint to survival. Therefore, the informal sector is an important buffer against livelihood shocks in situations of crisis. However, its inherent limitations imply that promoting livelihood resilience among urban residents during lockdowns and similar shocks may necessitate harnessing both formal and informal safety nets. Full article

During the coronavirus pandemic, buying and consumption patterns of US consumers shifted towards contactless buying. While the topic of online buying is well explored within the existing literature on this topic, purchasing fruit from a vending machine is still yet to be investigated. This exploratory study used quantitative data to examine the factors driving US consumers’ willingness to try, buy and pay a premium for fruit from vending machines. An online survey of 391 US consumers was conducted to fill this research gap between 7 July and 10 July 2022. This survey was distributed via Amazon Mechanical Turk, a crowdsourcing platform which is widely used for consumer research. Smart PLS 4 facilitated the Partial Least Squares Structural Equation Modeling (PLS-SEM) analysis, as this method well suited for testing exploratory models with complex relations between the latent variables. Results indicated that COVID-19 pandemic-related benefits, quality benefits, value-related benefits and experiential benefits were the most important predictors that determined willingness to try, buy and pay a price premium when purchasing fruit from a vending machine. Full article

Cities around the world have been hit by the COVID-19 crisis. The worst consequences of the pandemic are closely related to urban areas. Many studies investigated the impact of COVID-19 on people but there are few studies that have investigated the satisfaction level of university students during the COVID-19 lockdown at the neighborhood level. Therefore, the aim of this study is to investigate the satisfaction of university students at the neighborhood level during the COVID-19 lockdown and investigate the experience of online education during that period—if they received any. An online survey was conducted involving university students of different countries, and a total of 427 responses (n = 427) were received and analyzed using the CHAID model. Results show that comfort at residences during the COVID-19 lockdown was affected by the neighborhood environment (viz., greenery, pleasant views, independent housing with gardening facilities), transportation (i.e., saving 1–2 commuting hours on a daily basis and safety from traffic hazards), and the provision of online education (i.e., effectiveness, such as traditional methods of education and the opportunity to connect with field experts). Thus, it can be concluded that providing green neighborhoods, detached or terraced houses (townhouses) with visual connection, and gardening facilities for the residents should be encouraged in the future because these types of neighborhoods are not only comfortable in ordinary situations but also provide comfort during critical periods such as COVID-19 lockdowns. It can also be concluded that a hybrid style of education should be encouraged for universities, as it can save travel time, provide safety from traffic, and provide more opportunities to become connected with international experts through online guest lectures, seminars, and workshops. Full article

The purpose of this study was to determine the seropositivity of circulating viral pathogens and their association with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seropositivity. In a cross-sectional design, inhabitants (aged 10–60 years) of the slum and surrounding non-slum areas of Dhaka and Chattogram Metropolitan cities in Bangladesh were enrolled from October 2020 to February 2021. Antibodies to SARS-CoV-2, influenza B, parainfluenza, respiratory syncytial virus (RSV), human coronavirus HKU1 (HCoV-HKU1), dengue and chikungunya viruses were determined in plasma. The association of SARS-CoV-2 seropositivity with seropositivity to other viruses was assessed using the multi-variate logistic regression model. Seroprevalence of SARS-CoV-2, influenza B, RSV, dengue, chikungunya, HCoV-HKU1 and the parainfluenza virus were 68.3%, 98%, 50.0%, 16.5%, 15.5%, 3.36% and 0.0%, respectively. Individuals seropositive for RSV had lower odds (OR = 0.60; 95% CI= 0.49, 0.73) of SARS-CoV-2 seropositivity compared to RSV-seronegative individuals. Conversely, higher odds of SARS-CoV-2 seropositivity were observed in participants seropositive for dengue (OR= 1.73; 95% CI = 1.14, 2.66, only in slum) or chikungunya (OR = 1.48; 95% CI = 1.11, 1.95) compared to their seronegative counterparts. The study findings indicated that exposure to vector-borne virus dengue or chikungunya enhance, while antibodies to respiratory virus RSV decrease, the serological response to SARS-CoV-2. Full article