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1.
preprints.org; 2024.
Preprint in English | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.0517.v1

ABSTRACT

This study explores how the covid-19 pandemic affected some psychological factors in people who got tattoos during or after the lockdown, the psychological factors assessed were self-esteem, risk taking behaviour, body image and locus of control. The study used a quantitative, between-subjects design to investigate the experiences of participants who acquired tattoos during the pandemic compared to those who did not. The results showed that participants who got a tattoo during the pandemic reported higher levels of self-esteem and body image satisfaction compared to those who did not get a tattoo. Furthermore, the findings suggest that individuals with tattoos may have a more external locus of control. Participants with tattoos exhibited higher levels of risk-taking behaviour compared to those without tattoos, furthermore sex affected risk-taking behaviour in tattooed individuals, and females with tattoos displayed a higher risk taking tendency than their tattooed male counterparts. Further research needs to be done while acknowledging the limitations of this study. Overall, this study is pivotal in establishing how the pandemic may have affected the aforementioned psychological factors in people with tattoos. It also adds to the growing body of literature in body modification and psychology.


Subject(s)
COVID-19
2.
ssrn; 2024.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.4752595

Subject(s)
COVID-19
4.
ssrn; 2024.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.4752545

Subject(s)
COVID-19
6.
preprints.org; 2024.
Preprint in English | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.0676.v1

ABSTRACT

ABSTRACT Background: To date, the COVID-19 pandemic has been the foremost health concern for humankind in the new millennia. This paper aims to describe the related hospitalizations in Italy during the first two years of the health emergency. Design and methods: This is a retrospective, population-based study of Italian hospitalizations for patients diagnosed with COVID-19 during the 2020-2021 period, extracted from the National Hospital Discharge Registry. The outcome variables considered include hospital admissions, costs, and length of stay, among other hospitalization-level variables. Costs were estimated through the charges associated with the Diagnosis-Related Group and Major Diagnostic Categories coding system, plus an additional cost attributed to COVID-19 admissions. To these charges was added an extra cost defined by the ministry of health. Results: In Italy, there were 357,354 hospitalizations for COVID-19 attributed to 298,856 patients in 2020 and 399,043 hospitalizations for COVID-19 attributed to 333,447 patients in 2021. COVID-19 patients faced a transfer rate thrice that of other patients. Hospitalizations were concentrated predominantly in the northern regions, particularly in the first year. Hospitalization rates varied by age in a sine wave pattern, peaking in the youngest and oldest age groups, with mortality rates escalating with age— tending to remain below 3% for those under 44 but surging to 40% in individuals over 75. The financial impact of COVID-19 hospitalizations was substantial, with total costs reaching €3.97 billion in 2020 and €4.99 billion in 2021. Costs per admission and per day also rose, from €11,112 and €807 in 2020 to €12,503 and €844 in 2021, respectively. Excluding the added financial burden of COVID-19, costs would have been notably lower. Hospitalizations involving continuous invasive mechanical ventilation were particularly costly (about 24.000 euros x admission), reflecting the significant resources required for these treatments. Conclusion: Implementing a protective pad around the entire health system that leverages networks of family doctors and nurses, connected in real time to the entire health system, can be crucial. Such a network, tasked with monitoring the local epidemiological situation, protecting vulnerable individuals also through telehealth visits, and establishing a triage system for infections in the initial phase, may effectively help in managing virus spread and protecting hospitals from unpredictable waves of admission demand. Strengthening primary health care could be a decisive factor for the future and enhance the system's resilience in facing new challenges.


Subject(s)
COVID-19
7.
ssrn; 2024.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.4751735

Subject(s)
COVID-19
8.
preprints.org; 2024.
Preprint in English | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.0572.v1

ABSTRACT

The knowledge of COVID-19 impact on the human body has increased rapidly. Although many people recover from COVID-19, some continue to experience persistent symptoms that have been identified as Long COVID. This condition can have a severe impact on quality of life, and it remains a significant concern for medical professionals and researchers. One of the key components of the SARS-CoV-2 virus that enables it to enter human cells is the spike (S) protein. Recent studies have revealed a complex network of interactions between G proteins, spike (S) protein, and the Renin-Angiotensin System (RAS) may be responsible, at least in part, for long COVID. SARS-CoV-2 can also affect the brain, leading to neurological symptoms such as confusion, memory loss, and fatigue. Increasing evidence suggests that COVID-19 is not just a respiratory illness since it is likely that the virus could influence signal transduction pathways such as G-protein-coupled receptor (GPCR), among others, in the brain, either directly or indirectly, affecting neural functions. These interactions with the spike (S) protein and RAS, alongside the brain, are complex and require deep research to understand their implications for Long COVID-19 manifestation fully. While recent research has shed light on the complex interactions between G proteins, spike (S) protein, the brain, and the angiotensin system, this article explores these interconnected pathways and their implications for long COVID-19 manifestations. The present review summarises current research on different molecular mechanisms in Long COVID pathophysiology and may help identify possible targets or new strategies for the diagnosis and treatment.


Subject(s)
COVID-19 , Fatigue , Memory Disorders , Mastocytosis, Systemic , Severe Acute Respiratory Syndrome , Confusion
9.
preprints.org; 2024.
Preprint in English | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.0562.v1

ABSTRACT

Background: SARS-CoV-2 Omicron JN.1 has the highest number of amino acid mutations in its receptor binding domain (RBD) and has acquired a hallmark L455S mutation. The immune evasion capability of JN.1 is a subject of scientific investigation. The US CDC used RT-qPCR SGTF as the proxy indicator of JN.1 infections for evaluation of the effectiveness of updated monovalent XBB.1.5 COVID-19 vaccines against JN.1 and recommended that all persons aged ≥6 months should receive an updated COVID-19 vaccine dose. Objective: Recommend Sanger sequencing for diagnosis of JN.1 infections to generate the data based on which guidelines are made to direct vaccination policies. Methods: The RNA in nasopharyngeal swab specimens from patients with clinical respiratory infection was subjected to nested RT-PCR, targeting a 398-base segment of the N-gene and a 445-base segment of the RBD of SARS-CoV-2 for amplification. The DNA sequences were analyzed for amino acid mutations. Results: The N-gene sequence showed Q229K, usually associated with Omicron BA.2.86 (+JN.1). The RBD sequence showed 24 amino acid mutations, including the hallmark L455S mutation for JN.1 and the V483del for BA.2.86 lineage. Conclusions: The CDC should consider Sanger sequencing of the RBD to diagnose JN.1 infections for statistical analysis in making vaccination policies.


Subject(s)
COVID-19 , Severe Acute Respiratory Syndrome , Respiratory Tract Infections
10.
biorxiv; 2024.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2024.03.08.584120

ABSTRACT

The evolution of SARS-CoV-2 variants and their respective phenotypes represents an important set of tools to understand basic coronavirus biology as well as the public health implications of individual mutations in variants of concern. While mutations outside of Spike are not well studied, the entire viral genome is undergoing evolutionary selection, particularly the central disordered linker region of the nucleocapsid (N) protein. Here, we identify a mutation (G215C), characteristic of the Delta variant, that introduces a novel cysteine into this linker domain, which results in the formation of a disulfide bond and a stable N-N dimer. Using reverse genetics, we determined that this cysteine residue is necessary and sufficient for stable dimer formation in a WA1 SARS-CoV-2 background, where it results in significantly increased viral growth both in vitro and in vivo. Finally, we demonstrate that the N:G215C virus packages more nucleocapsid per virion and that individual virions are larger, with elongated morphologies.

11.
biorxiv; 2024.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2024.03.10.584306

ABSTRACT

As SARS-CoV-2 continues to spread and mutate, tracking the viral evolutionary trajectory and understanding the functional consequences of its mutations remain crucial. Here, we characterized the antibody evasion, ACE2 receptor engagement, and viral infectivity of the highly mutated SARS-CoV-2 Omicron subvariant BA.2.87.1. Compared with other Omicron subvariants, including EG.5.1 and the current predominant JN.1, BA.2.87.1 exhibits less immune evasion, reduced viral receptor engagement, and comparable infectivity in Calu-3 lung cells. Intriguingly, two large deletions ({Delta}15-26 and {Delta}136-146) in the N-terminal domain (NTD) of the spike protein facilitate subtly increased antibody evasion but significantly diminish viral infectivity. Collectively, our data support the announcement by the USA CDC that the public health risk posed by BA.2.87.1 appears to be low.

12.
preprints.org; 2024.
Preprint in English | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.0616.v1

ABSTRACT

The intricate mechanisms of the immune response elicited by vaccines and the interplay between the immune system and the central nervous system (CNS) are poorly understood. This review explores these mechanisms, emphasizing the interplay between the immune system and the central nervous system (CNS). A critical aspect is the examination of how vaccine-induced immune responses can interact with the CNS, influencing neuroinflammation and neuroimmune interactions. Furthermore, the link between vaccination and persistent symptoms observed in long-COVID patients is discussed. Vaccination initiates a complex cascade of events, starting with the production of specific proteins, such as S1/S2 spike proteins, leading to robust immune activation in the axillary lymph nodes. The role of macrophages and antigen-presenting cells (APCs) in cytokine production, antigen presentation, and the stimulation of B and T cells highlights the sophistication of the adaptive immune response. The migration of immune cell-derived exosomes to the brain plays a dynamic role in CNS inflammation, neurodegenerative processes and long COVID. On the other hand, the prolonged presence of viral and vaccine-derived spike proteins may contribute to the complex pathophysiology of Long-COVID, shedding light on the delicate balance between beneficial immune responses and possible adverse neurological outcomes of vaccination. It is worth rigorous monitoring and further research to understand the mechanisms of neuroinflammation and the persistence of spike proteins and their long-term effects on the brain, emphasising the importance of a nuanced approach to vaccine safety and efficacy in the context of COVID-19 and beyond.Principio del formulario


Subject(s)
Inflammation , COVID-19
13.
preprints.org; 2024.
Preprint in English | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.0613.v1

ABSTRACT

The Covid-19 pandemic was a challenge for the whole world and it had major second-ary effects on the health of the population and the environment. The viral infection caused, in many situations, secondary bacterial infections, especially enteric infections by destabilizing the balance of the gastrointestinal microbiota. The large-scale use of antibiotics and biocides both for curative and preventive purposes has determined an increase in bacterial resistance and at the same time the possibility of the multiplica-tion of pathogenic microorganisms and their transfer in natural environments. Wastewater is the main vector of faecal microorganisms that favour their dissemina-tion in natural aquatic ecosystems. The present paper represents a sub-study of the RADAR project with the aim of demonstrating the effect of the Covid-19 pandemic on the microbiological quality of wastewater from sewage treatment plants in Romania and its impact on receiving rivers. In order to highlight different and important areas of Romania, 3 cities from the east, center and west were selected for the evaluation of microbiological quality of influent and effluent sewage in WWTPs between ante-Covid-19 and the peak period of the Covid-19 pandemic, when the Covid-19 pandemic had a direct consequence on WWTPs processes. Our study showed the high-er contamination with fecal bacteria based on higher Covid-19 incidence. The in-creased usage of pharmaceutical compounds, at their turn, increased the number of resistant bacteria reaching the environment via WWTP effluents.


Subject(s)
Virus Diseases , Bacterial Infections , COVID-19
14.
preprints.org; 2024.
Preprint in English | PREPRINT-PREPRINTS.ORG | ID: ppzbmed-10.20944.preprints202403.0647.v1

ABSTRACT

Artificial Intelligence (AI) and Machine Learning (ML) approaches that could learn from large data sources have been identified as useful tools to support clinicians in their decisional process; AI and ML implementations have had a rapid acceleration during the recent COVID-19 pandemic. However, many ML classifiers are “black box” to the final user, since their underlying reasoning process is often obscure. Additionally, the performance of such models suffer from poor generalization ability in presence of dataset shift. Here, we present a comparison between an explainable-by-design (“white box”) model (Bayesian Network (BN)) versus a black-box model (Random Forest), both studied with the aim to support clinicians of Policlinico San Matteo University Hospital in Pavia (Italy) during the triage of COVID-19 patients. Our aim is to evaluate whether the BN predictive performances are comparable with those of a widely used but less explainable ML model such as Random Forest and to test the generalization ability of the ML models across different waves of the pandemic.


Subject(s)
COVID-19
15.
arxiv; 2024.
Preprint in English | PREPRINT-ARXIV | ID: ppzbmed-2403.06435v1

ABSTRACT

Health experts have suggested that social distancing measures are one of the most effective ways of preventing the spread of Covid-19. Research primarily focused on large Covid filled droplets suggested that these droplets can move further than regulated social distancing guidelines (2 meters apart) in the presence of wind. This project aims to model the paths of smaller Covid virions that last longer in the air to see if they also move beyond social distancing norms in the presence of wind. By numerically solving a 2-dimensional Langevin equation for 3000 particles and modeling wind as one-dimensional and steady, velocities were found that translated into particles' positions. With wind, infectious doses of virions appeared to travel farther and faster, increasing the risk of infection before dispersion. The two-dimensional model given implies that social distancing norms are reasonable in cases with no wind, yet not conservative enough when there is wind.


Subject(s)
COVID-19
16.
authorea preprints; 2024.
Preprint in English | PREPRINT-AUTHOREA PREPRINTS | ID: ppzbmed-10.22541.au.171015681.17029202.v1

ABSTRACT

Background: We aimed to compare the epidemiological and clinical characteristics of coronavirus disease 2019 (COVID-19) in people living with human immunodeficiency virus (HIV) (PLWH) with those in the general population. Methods: This nationwide descriptive epidemiological study was conducted in South Korea between January 2020 and February 2022. The National Health Insurance claims data covering the whole nation were collected through the Health Insurance Review and Assessment Service. Results: Among 3,653,808 individuals who were diagnosed with COVID-19, 1,311 (0.04%) were PLWH. All the PLWH received antiretroviral therapy, and 26.47% had more than one underlying disease other than HIV infection. The overall in-hospital mortality rates of PLWH and the general population were 0.76% and 0.25%, respectively (P=0.002). According to the Cox proportional hazard model, no significant difference was observed in the in-hospital mortality rate [hazard ratio (HR): 1.80, 95% confidence interval (CI): 0.70–4.67] between PLWH and the general population. However, progression to severe or critical COVID-19 was more common in PLWH (HR: 2.70, 95% CI: 1.37–5.33). In PLWH diagnosed with COVID-19, a multivariable Cox regression analysis found old age (≥60 years old) (HR: 6.9; 95% CI 2.57–18.56) and diabetes mellitus (HR: 5.13; 95% CI: 2.02–13.00) as the independent risk factors for severe or critical COVID-19. Conclusions: PLWH had a significantly higher risk of severe or critical COVID-19 than that of the general population. Our findings suggest the need for applying differentiated strategies to decrease the impact of COVID-19 on PLWH.


Subject(s)
Virus Diseases , HIV Infections , Diabetes Mellitus , COVID-19
17.
authorea preprints; 2024.
Preprint in English | PREPRINT-AUTHOREA PREPRINTS | ID: ppzbmed-10.22541.au.171018163.37709709.v1

ABSTRACT

The prevalence of COVID-19 in the community has become more difficult to gauge utilizing clinical testing due to a decrease in reported test results stemming from the availability of at-home test kits and a reduction in the number of cases seeking medical treatment. The purpose of this study was to examine the trend of diminishing correlation between reported clinical cases of COVID-19 and wastewater-based surveillance epidemiological data as home testing became available in the Eastern Upper Peninsula of Michigan. Wastewater grab samples were collected weekly from 16 regional locations from June 2021-December 2022. Samples were analyzed for SARS-CoV-2 N1 and N2 viral particles using reverse transcriptase digital droplet polymerase chain reaction (RT ddPCR). N1 and N2 gene copies were correlated with clinical cases. The t-test was used to determine correlation deterioration point. Clinical cases post-deterioration were calculated for high-correlated pre-deterioration locations using linear regression. Correlation between the wastewater-based surveillance of SARS-CoV-2 and reported clinical cases deteriorated after February 1, 2022. This corresponds with the timeframe in which commercially available at-home test kits became available in the United States. The increase in at-home testing for SARS-CoV-2 likely contributed to the decrease in reported clinical positive tests in early 2022, providing an unrealistic picture of the presence of Covid-19 in the community. As measures to reduce exposure such as personal masking, clinical testing, social isolating, and quarantining continue to decline, wastewater surveillance for the presence of SARS-CoV-2 may be the best method for public health professionals to remain aware of virus dynamics in localized regions. Time-series modeling adds another layer of information when clinical data is unobtainable or underreported.


Subject(s)
COVID-19
18.
medrxiv; 2024.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2024.03.08.24304006

ABSTRACT

Introduction: People living with HIV (PLWH) can exhibit impaired immune responses to vaccines. Accumulating evidence indicates that PLWH, particularly those receiving antiretroviral therapy, mount strong antibody responses to COVID-19 vaccination, but fewer studies have examined cellular immune responses to vaccination. We measured SARS-CoV-2 spike-specific CD4+ and CD8+ T cell responses generated by two and three doses of COVID-19 vaccine in PLWH receiving antiretroviral therapy, compared to control participants without HIV. We also quantified T cell responses after post-vaccine breakthrough infection, and receipt of fourth vaccine doses, in a subset of PLWH. Methods: We quantified CD4+ and CD8+ T cells reactive to overlapping peptides spanning the ancestral SARS-CoV-2 spike protein in 50 PLWH and 87 controls without HIV, using an activation induced marker (AIM) assay. All participants remained SARS-CoV-2 naive until at least one month after their third vaccine dose. SARS-CoV-2 infection was determined by seroconversion to nucleocapsid (N) antigen, which occurred in 21 PLWH and 38 controls post-third dose. Multivariable regression analyses were used to investigate relationships between sociodemographic, health and vaccine-related variables and vaccine-induced T cell responses, as well as breakthrough infection risk. Results: A third vaccine dose boosted spike-specific CD4+ and CD8+ T cell frequencies significantly above those measured after the second dose (all p<0.0001). Median T cell frequencies did not differ between PLWH and controls after the second dose (p>0.1), but CD8+ T cell responses were modestly lower in PLWH after the third dose (p=0.02), an observation that remained significant after adjustment for sociodemographic, health and vaccine-related variables (p=0.045). In PLWH who experienced breakthrough infection, median T cell frequencies increased even higher than those observed after three vaccine doses (p<0.03), and CD8+ T cell responses in this group remained higher even after a fourth vaccine dose (p=0.03). In multivariable analysis, the only factor associated with increased breakthrough infection risk was younger age, consistent with the rapid increases in SARS-CoV-2 seropositivity among younger adults in Canada after the initial appearance of the Omicron variant. Conclusion: PLWH receiving antiretroviral therapy mount strong T cell responses to COVID-19 vaccines that can be enhanced by booster doses or breakthrough infection.


Subject(s)
HIV Infections , COVID-19 , Breakthrough Pain
19.
biorxiv; 2024.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2024.03.11.584367

ABSTRACT

SARS-CoV-2 still presents a global threat to human health due to the continued emergence of new strains and waning immunity amongst vaccinated populations. Therefore, it is still relevant to investigate potential therapeutics, such as therapeutic interfering particles (TIPs). Mathematical and computational modelling are valuable tools to study viral infection dynamics for predictive analysis. Here, we expand on the previous work by Grebennikov et al. (2021) on SARS-CoV-2 intra-cellular replication dynamics to include defective interfering particles (DIPs) as potential therapeutic agents. We formulate a deterministic model that describes the replication of wild-type (WT) SARS-CoV-2 virus in the presence of DIPs. Sensitivity analysis of parameters to several model outputs is employed to inform us on those parameters to be carefully calibrated from experimental data. We then study the effects of co-infection on WT replication and how DIP dose perturbs the release of WT viral particles. Furthermore, we provide a stochastic formulation of the model that is compared to the deterministic one. These models could be further developed into population-level models or used to guide the development and dose of TIPs.


Subject(s)
Virus Diseases , Coinfection
20.
biorxiv; 2024.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2024.03.11.583978

ABSTRACT

The rapid evolution of SARS-CoV-2 variants presents a constant challenge to the global vaccination effort. In this study, we conducted a comprehensive investigation into two newly emerged variants, BA.2.87.1 and JN.1, focusing on their neutralization resistance, infectivity, antigenicity, cell-cell fusion, and spike processing. Neutralizing antibody (nAb) titers were assessed in diverse cohorts, including individuals who received a bivalent mRNA vaccine booster, patients infected during the BA.2.86/JN.1-wave, and hamsters vaccinated with XBB.1.5-monovalent vaccine. We found that BA.2.87.1 shows much less nAb escape from WT-BA.4/5 bivalent mRNA vaccination and JN.1-wave breakthrough infection sera compared to JN.1 and XBB.1.5. Interestingly. BA.2.87.1 is more resistant to neutralization by XBB.15-monovalent-vaccinated hamster sera than BA.2.86/JN.1 and XBB.1.5, but efficiently neutralized by a class III monoclonal antibody S309, which largely fails to neutralize BA.2.86/JN.1. Importantly, BA.2.87.1 exhibits higher levels of infectivity, cell-cell fusion activity, and furin cleavage efficiency than BA.2.86/JN.1. Antigenically, we found that BA.2.87.1 is closer to the ancestral BA.2 compared to other recently emerged Omicron subvariants including BA.2.86/JN.1 and XBB.1.5. Altogether, these results highlight immune escape properties as well as biology of new variants and underscore the importance of continuous surveillance and informed decision-making in the development of effective vaccines.

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