COVID, Volume 1, Issue 2 (October 2021) – 8 articles

In this study, we developed a compartmental SIRD model to analyze and forecast the transmission dynamics of the COVID-19 pandemic in Bangladesh during the third wave caused by the Indian delta variant. With the help of the nonlinear system of differential equations, this model can analyze the trends and provide reliable predictions regarding how the epidemic would evolve. The basic reproduction number regarding the pandemic has been determined analytically. The parameters used in this model have been estimated by fitting our model to the reported data for the months of May, June, and July 2021 and the goodness of fit of the parameter’s value has been found by the respective regression coefficients. Further, we conducted a sensitivity analysis of the basic reproduction number and observed that decreasing the transmission rate is the most significant factor in disease prevention. Our proposed model’s appropriateness for the available COVID-19 data in Bangladesh has been demonstrated through numerical simulations. According to the numerical simulation, it is evident that a rise in the transmission rate leads to a significant increase in the infected number of the population. Numerical simulations have also been performed by using our proposed model to forecast the future transmission dynamics for COVID-19 over a longer period of time. Knowledge of these forecasts may help the government in adopting appropriate measures to prepare for unforeseen situations that may arise in Bangladesh as well as to minimize detrimental impacts during the outbreak. Full article

COVID-19 patients suffer from hypercoagulation and activated immune-inflammatory pathways. The current study examined the relationship between specific complements and coagulation abnormalities associated with chest CT scan anomalies (CCTAs) and peripheral oxygen saturation (SpO2) in COVID-19 patients. Serum levels of complement C3 and C4, and thromboxane A2 (TxA2) and prostacyclin (PGI2) were measured using an ELISA and albumin, calcium, and magnesium by using the spectrophotometric method in 60 COVID-19 patients and 30 controls. C3 and C4 were significantly decreased (p < 0.001), and TxA2 and PGI2 significantly increased (p < 0.001) in the COVID-19 patients compared with the controls with the highest levels in the CCTA patients’ group. Neural networks showed that a combination of C3, albumin, and TxA2 yielded a predictive accuracy of 100% in detecting COVID-19 patients. SpO2 was significantly decreased in the COVID-19 patients and was inversely associated with TxA2 and PGI2, and positively with C3, C4, albumin, and calcium. Patients with positive IgG results show significantly higher SpO2, TxA2, PGI2, and C4 levels than IgG-negative patients. CCTAs were accompanied by lower SpO2 and albumin and increased PGI2 and TxA2 levels, suggesting that interactions between immune-inflammatory pathways and platelet hyperactivity participate in the pathophysiology of COVID-19 and, consequently, may play a role in an enhanced risk of hypercoagulability and venous thromboembolism. These mechanisms are aggravated by lowered calcium and magnesium levels. Full article

Non-pharmaceutical interventions have been implemented intermittently for more than a year in most countries of the world to mitigate the COVID-19 epidemic. In France, while the vaccination campaign is progressing, the French government has decided to remove many public health restrictions such as business closure, lockdowns, and curfews. Nonetheless, social distancing, mask wearing, and hand washing (also called barrier gestures) are still recommended. We utilize an age-structured compartmental SEIR model that takes into account the SARS-CoV-2 waning immunity, vaccination, and increased transmissibility from variants of concern to estimate if barrier gestures can be relaxed without causing a resurgence of severe infections. This model assumes that the susceptibility to infection is a function of immunity status, which depends on initial infection severity and vaccination status. It is calibrated on confirmed COVID-19 cases from the French surveillance database, and accounts for changes in contact behaviors due to the implementation of nation-wide public health policies. We study the partial and full relaxation of barrier gestures occurring from August to December 2021 under various immunity duration assumptions. Maintaining the application of barrier gestures appears essential to avoid a resurgence of severe infections that would exceed French health care capacities, while surmounting vaccine hesitancy represents the key to consider their relaxation. Immunity duration assumptions significantly influence the short-term dynamic of the epidemic, which should be considered for further modelling. Full article

Recently, an inverse relationship between incidence of COVID-19 and seasonal aerosolization of mold spores was demonstrated. Analyses of that relationship suggested mold spores compete with SARS-CoV-2 virions for a receptor on the pulmonary epithelial surface. By inference, the operative receptor was proposed to be Toll-like receptor 4, with surface-localized virions being responsible for symptomatology. In this report, the pathogenesis of COVID-19 is further developed, with a focus on a role for surfactant protein D in the process. This developed proposal provides both mechanistic understanding and suggested treatments of COVID-19. Full article

Objectives: Our study aimed to investigate the frequency of malignant cardiac arrhythmias in hospitalized patients receiving hydroxychloroquine alone and those receiving a combination of hydroxychloroquine with azithromycin, as well as the quantitative extent of QT prolongation within Tisdale Risk Score (TRS) categories. Background: There have been over 33 million cases of SARS-CoV-2 (COVID-19) resulting in over 600,000 deaths in the United States. As the current COVID-19 pandemic continues, numerous medications have been administered to attempt to treat patients afflicted by the disease. While hydroxychloroquine has been in use for decades for rheumatologic and infectious disease processes, it does have potential cardiotoxicity related to drug-induced QT prolongation. Drug-induced QT prolongation has an increased risk of arrhythmogenicity, potentially progressing into torsades de pointes (TdP) and increased patient mortality. The relationship between QT prolongation and TdP is complex and inexact, but there remains optimism regarding the use of these medications in the treatment of COVID-19 despite limited data on their true efficacy. Methods: We retrospectively identified 75 patients who were admitted with COVID-19 and underwent treatment with hydroxychloroquine for 5 days. The hydroxychloroquine protocol was defined as an initial dose of 400 mg BID for the first day, followed by 400 mg daily for the next 4 days. Baseline demographics, medications, medical histories, lab values, ECG QT intervals, and Tisdale Risk Categories were collected for all patients. Results: Seventy-four (98.7%) patients completed the full course of hydroxychloroquine. There were 41 males (54.7%) and 34 females (45.3%). Average length of stay was 8.9 days (95% CI: 7.5, 10.2). One patient who could not complete the course due to inability to swallow medication tablets. There were no reports of new arrythmias or incidence of torsades de pointes during the study. Seventy-two patients (96%) were taking at least 2 QT prolonging medications. The average corrected QT intervals were as follows: day 1 of admission was 421.62 milliseconds (n = 66, 95% CI: 412.19, 431.05), day 2 was 431.50 ms (n = 30, 95% CI: 416.34, 446.66), day 3 was 433.48 ms (n = 23, 95% CI: 413.34, 453.61), day 4 was 427.59 ms (n = 17, 95% CI: 400.83, 454.35), and day 5 was 444.28 ms (n = 18, 95% CI: 428.43, 460.12). The corrected QT interval prolonged by 22.66 ms from day 1 to day 5 (p = 0.03) in the overall population. Conclusion: There were no patients who experienced arrhythmogenicity or Torsades de Pointes despite a statistically significant increase in QTc intervals after patients received the 5-day course of hydroxychloroquine for treatment of COVID-19. Full article

Introduction: While mitigation procedures are needed to prevent the continuous spread of COVID-19, they may, in turn, negatively impact individuals’ mental health. Therefore, the current study aimed to investigate the relationships between loneliness, rumination, and depression, as well as the mediating role of rumination in the relationship between loneliness and depression in university students during the COVID-19 pandemic. Methods: A cross-sectional online survey was circulated, collecting a final sample of 288 university students (M_age = 22.01, SD = 3.45, range = 18–55, 75.7% female). Study variables were measured utilizing self-report questionnaires. Results: In line with the hypotheses, rumination partially mediated the relationship between loneliness and depression. Discussion: Therefore, ruminative thoughts may be one of the key factors contributing to lonely university students’ susceptibility to depressive symptoms during the COVID-19 pandemic. Full article

Viruses are the most common causative agents of inflammation in the oral cavity and throat region. Most respiratory tract infections are self-limiting and require no specific treatment. However, patients often use different self-medication therapies that can treat both the symptoms and the cause. Throat lozenges with a fixed combination of benzydamine hydrochloride and cetypiridinium chloride (BH/CPC) have been shown to provide effective symptomatic relief for sore throat, but their effect on viruses has not been investigated to date. The antiseptic, cetylpyridinium chloride (CPC), has already been described as a successful bactericide. In addition, there are some studies suggesting its efficacy against certain enveloped viruses. Thus, the aim of our study was to examine the virucidal activity of CPC and a combination of BH/CPC as a free active substance or as lozenge on SARS-CoV-2 in vitro. Under in-laboratory simulated conditions of lozenge administration, we incubated SARS-CoV-2 with three different concentrations of each of the active substances, CPC, free BH/CPC or BH/CPC, as a lozenge suspension for 1 min, 5 min and 15 min of contact time. Infective viral particles were detected in cell cultures and the viral titre was calculated accordingly. Our results show that all active substances in high-concentration suspensions, as well as a medium concentration of the BH/CPC combination, exhibited a 4-log reduction in viral titre. Additionally, the highest concentration of BH/CPC as a lozenge had a faster virucidal effect compared to CPC as a free active substance alone, since a contact time as short as 1 min reduced the initial virus concentration by more than 4-log. This study demonstrates the effective strong virucidal effect of the lozenge, with the possibility of viral load reduction in the oral cavity and, consequently, reduced risk of viral transmission. Full article

Nepal has suffered two waves of SARS-CoV-2 infections, one in the year 2020 and another in the year 2021. Although the government of Nepal keeps a detailed record of daily coronavirus infections and deaths throughout the country, and publishes the result every day, genomic surveillance of mutants in the country has lagged behind. Sequencing of COVID-19 samples has been conducted sporadically during the pandemic. From the GISAID database, 127 high-quality sequences deposited by different health authorities in Nepal were collected and analyzed. From the analysis, it can be concluded that at least two variants of concern, alpha and delta, and one variant of interest, kappa, were detected in Nepal in 2021. As in other countries, the delta variant outcompeted the kappa and alpha variants and by July 2021 had established itself as the dominant variant. It can be hypothesized that the second wave in Nepal was primarily caused by the delta variant. Further, phylogenetic tree analysis suggests cases of local transmission and global transmission of coronavirus. This analysis reveals the global nature of the disease, where variants arising in one part of the world can quickly spread to other parts of the world and can also spread through individual communities. This paper highlights a need to structure public policy of Nepal to target the delta variant since it has become the predominant variant in Nepal. A further policy suggestion is to appropriately sample and sequence genomes of SARS-CoV-2 at regular intervals to understand the dynamics of variants in the population. Full article