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This page contains a variety of information related to COVID-19 available from MDPI, including journal articles, special issues, and preprints, among others.
Inflation, recognized as a social determinant of health (SDOH), significantly affects the daily lives of individuals through the rising costs of food, housing, and other basic needs, all of which are public health concerns. Since the COVID-19 pandemic, inflation has become a prominent
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Inflation, recognized as a social determinant of health (SDOH), significantly affects the daily lives of individuals through the rising costs of food, housing, and other basic needs, all of which are public health concerns. Since the COVID-19 pandemic, inflation has become a prominent concern in the U.S. and has been linked to increased stress and poor mental health among adults. While data on inflation is tracked routinely, how it is discussed publicly is understudied. Social media platforms provide insights into how inflation is framed and experienced by the public, and these assessments may be used to determine public health needs and policy advocacy. In this study, we conducted a time-bound, platform-specific case study of inflation-related discourse on X (formerly Twitter). Analysis revealed a predominance of negative sentiments (68.5%) including frustration and distrust. Posts primarily concerned monetary policy/government spending (31.6%), Federal Reserve interest rates/financial markets (24.5%), and U.S. presidential politics (12.9%). The users did not explicitly discuss personal-level hardships, and the discussions largely focused on macro-level issues framed in polarized political perspectives. These patterns matter for public health because institutional trust shapes support for social and health policies. Our study findings suggest a fragmented social environment that may exacerbate community-wide anxiety and challenge health promotion efforts and the need for public health surveillance through surveys or personal interviews to identify and address the psychological burden of inflation.
Full article
Background/Objectives: This review examined how different levels of U.S. food-security (FS) relate to dietary markers, informing the concept of nutrition security over the lifespan. Methods: The authors followed PRISMA-ScR guidelines. PubMed, CINAHL, Scopus, Embase, and CAB Abstracts were searched for eligible
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Background/Objectives: This review examined how different levels of U.S. food-security (FS) relate to dietary markers, informing the concept of nutrition security over the lifespan. Methods: The authors followed PRISMA-ScR guidelines. PubMed, CINAHL, Scopus, Embase, and CAB Abstracts were searched for eligible U.S.-based, English-language studies examining FS and dietary markers in free-living, disease-free populations, excluding COVID-19-era research. Two reviewers independently screened records in Covidence, with discrepancies resolved by a third reviewer. The percentage of studies evaluating >2 FS levels was determined. Dietary markers were classified into three domains: food and beverage (9 components), nutrient (16 components) and bioactive (2 components) markers. The percentages of studies with significant differences were estimated for each dietary domain. Results: Of 1069 records, 78 met full-text eligibility. Among these, 15% evaluated dietary markers across >2 FS levels. Among adults, differences by FS status were observed in 67% of assessed food and beverage components (6 out of 9), 50% of nutrient components (8 out of 16), and all evaluated bioactives (100%; 2 out of 2). Children exhibited differences in all assessed food and beverage components (100%; 9 out of 9) and 29% (2 out of 7) of nutrients by FS level. Adolescents had fewer dietary marker differences than children and adults. Findings among infants, pregnant women and older adults were limited, with no studies for lactating women. Conclusions: Low FS level is associated with poorer dietary markers across the lifespan compared with FS. Age-specific differences highlight the need for targeted interventions and nutrition security measures.
Full article
by
Sindre H. Hauan, Camilla H. Nundal, Sarah Lartey Jalloh, June Skudal, Elin Ekornes Håskjold, Sigrid Christiansen Bøe, Camilla Tøndel, Linn Marie Sørbye, Rebecca J. Cox and Karl A. Brokstad
Viruses2026, 18(6), 593; https://doi.org/10.3390/v18060593 (registering DOI) - 24 May 2026
Background. Lower respiratory tract infections remain a major cause of morbidity and mortality in infants worldwide. Newborns possess an immature immune system but acquire passive immunity through maternal antibodies transferred via the placenta (IgG) and breast milk (IgA). Maternal vaccination may enhance this
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Background. Lower respiratory tract infections remain a major cause of morbidity and mortality in infants worldwide. Newborns possess an immature immune system but acquire passive immunity through maternal antibodies transferred via the placenta (IgG) and breast milk (IgA). Maternal vaccination may enhance this protection. This study aimed to quantify antibody levels against respiratory viruses in serum and breast milk from lactating women. Methods. Serum and breast milk samples were collected from 26 lactating mothers. Antibody levels were measured using an indirect enzyme-linked immunosorbent assay (ELISA) targeting seven viral antigens: influenza A (A/Thailand, A/California), influenza B (B/Phuket, B/Austria), SARS-CoV-2 (Spike and receptor-binding domain, RBD) and RSV F pre-fusion protein. Antibody isotypes IgG, IgA and IgM were analysed. Results. Virus-specific IgG and IgA antibodies were detected in all samples. Breast milk showed the highest levels of IgA, whereas serum contained higher IgG levels. A moderate positive correlation was observed between serum and milk IgG. No correlation was found between serum IgG and milk IgA, but both levels were elevated. Conclusions. Breast milk and serum contain relatively high levels of antibodies against the tested respiratory viruses. The elevated levels of serum IgG and milk IgA indicate a coordinated defence between systemic and mucosal immunity in response to infections. The levels and correlation of specific isotypes point to the source of the antibodies: milk IgG probably originates from the blood, whereas milk IgA is produced locally.
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Although SARS-CoV-2 has been extensively studied from clinical, virological, and diagnostic perspectives, the problem of accurate automatic semantic segmentation of SARS-CoV-2 particles in electron microscopy images remains inadequately explored. Existing studies have largely focused on virus detection, classification, morphometry, or conventional image analysis,
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Although SARS-CoV-2 has been extensively studied from clinical, virological, and diagnostic perspectives, the problem of accurate automatic semantic segmentation of SARS-CoV-2 particles in electron microscopy images remains inadequately explored. Existing studies have largely focused on virus detection, classification, morphometry, or conventional image analysis, while comparatively little attention has been paid to pixel-level delineation of viral structures using specialised deep learning segmentation frameworks. To address this gap, we propose here a deep learning system based on convolutional neural networks (CNNs) combined with image processing techniques to establish semantic segmentation tools for the automatic identification of SARS-CoV-2. Our approach utilises the super-Euclidean pixels method as an intermediate layer within the CNN for semantic segmentation. We then compare its performance against the gradient vector flow (GVF) and Poisson inverse gradient (PIG) segmenters. The proposed CNN model surpassed the traditional GVF and PIG segmentation models, achieving the following metrics (mean ± variance): Dice similarity coefficient (DSC) = 0.9345 ± 0.0006; intersection over union (IoU) = 0.8782 ± 0.0018; sensitivity/true positive rate (TPR) = 0.9373 ± 0.0018; specificity/true negative rate (SPC) = 0.9517 ± 0.0012; accuracy = 0.9449 ± 0.0004; area under the ROC curve (AUC) = 0.9446 ± 0.0431; and Cohen’s Kappa = 0.9137 ± 0.0011. This method enables virologists to employ an automatic CNN-based segmentation tool for detecting SARS-CoV-2 and demonstrates superiority over GVF and PIG.
Full article
Coronavirus disease 2019 (COVID-19) has been associated with an increased long-term cardiovascular risk, potentially mediated by magnitude of the acute inflammatory response inflammation. Interleukin-6 (IL-6) and serum amyloid A (SAA) are key components of the inflammatory cascade and may serve as biomarkers of
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Coronavirus disease 2019 (COVID-19) has been associated with an increased long-term cardiovascular risk, potentially mediated by magnitude of the acute inflammatory response inflammation. Interleukin-6 (IL-6) and serum amyloid A (SAA) are key components of the inflammatory cascade and may serve as biomarkers of post-COVID cardiovascular vulnerability. This longitudinal observational study investigated the association between post- COVID-19 infection IL-6 and SAA levels and major cardiovascular events over a six-year follow-up period. A total of 97 individuals with documented prior SARS-CoV-2 infection were included. Circulating IL-6 and SAA concentrations were measured in the acute phase. The composite endpoint included incident arrhythmia, myocardial infarction, and all-cause mortality. Biomarker distributions were right-skewed and were therefore analyzed using non-parametric methods and penalized logistic regression models. During follow-up, 14.4% of participants experienced the composite endpoint. Individuals with adverse outcomes had significantly higher IL-6 and SAA levels compared with event-free participants. IL-6 demonstrated the strongest association with mortality, whereas SAA showed particularly robust associations with the composite endpoint, and with myocardial infarction. Both biomarkers independently predicted long-term adverse events. Circulating IL-6 and SAA concentrations measured during the acute phase of SARS-CoV-2 infection were analyzed in relation to long-term cardiovascular outcomes. These findings support the hypothesis that the magnitude of the acute inflammatory response during SARS-CoV-2 infection may be associated with long-term cardiovascular outcomes and suggest that combined assessment of IL-6 and SAA may have potential utility for hypothesis-generating prognostic signal requiring validation, pending validation in larger studies.
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Background: The COVID-19 pandemic has been a global crisis, affecting healthcare systems and professionals worldwide. This study investigates the prevalence and factors associated with burnout and insomnia among Greek physicians affiliated with the Athens Medical Association after the acute phase of the COVID-19
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Background: The COVID-19 pandemic has been a global crisis, affecting healthcare systems and professionals worldwide. This study investigates the prevalence and factors associated with burnout and insomnia among Greek physicians affiliated with the Athens Medical Association after the acute phase of the COVID-19 pandemic. Methods: Data were collected through an anonymous online survey distributed to active physician members of the Athens Medical Association between 15 June 2023 and 15 July 2023. Burnout was assessed using the Maslach Burnout Inventory (MBI), and insomnia was assessed using the Athens Insomnia Scale (AIS). Descriptive, unadjusted, and multivariable analyses were performed. Results: A total of 1023 physicians participated. Insomnia (AIS ≥ 6) affected 83.0% of the participants. Based on standard MBI cut-offs, 52.4% had high emotional exhaustion, 35.9% had high depersonalization, and 39.2% had low personal accomplishment. In multivariable logistic regression, older age was significantly associated with lower odds of insomnia, while public-sector employment and high concern about future career consequences were associated with higher odds. In multiple linear regression models, a higher AIS total score was significantly associated with higher emotional exhaustion and depersonalization and with lower personal accomplishment. Conclusions: These findings suggest high rates of insomnia and burnout in this physician sample. Greater insomnia was significantly associated with less favorable scores across all three burnout dimensions. Younger age, public-sector employment, and higher concern about future career consequences were associated with insomnia. These findings should be interpreted as associations, rather than causal effects.
Full article
The first webinar in the series, held on 17 April 2020, saw both Prof. Dr. Antoine Flahault, Director of the Institute of Global Health, University of Geneva, Switzerland, and Prof. Dr. Evelyne Bischof, Associate Professor, Shanghai University of Medicine and Health Sciences, Shanghai, China and Research physician, University Hospital of Basel, Basel, Switzerland speak on this topic.
The second webinar in the series, entitled “Coronaviruses: history, replication, innate immune antagonism”, saw Prof. Dr. Susan R. Weiss, Professor of Microbiology, Perelman School of Medicine, University of Pennsylvania speak on this topic.
WEBINAR 3: Could the COVID-19 Crisis be the Opportunity to Make Cities Carbon Neutral, Liveable and Healthy
The third webinar in this series was presented by Prof. Dr. Mark Nieuwenhuijsen, a world leading expert in environmental exposure assessment, epidemiology, and health risk/impact assessment with a strong focus and interest on healthy urban living.
WEBINAR 4: COVID-19 - Global Supply Chains and the SDGs
For the fourth webinar of this series, Prof. Dr. Max Bergman, Dr. Dorothea Schostok and Prof. Dr. Patrick Paul Walsh gave a presentation on Global Supply Chains and the SDGs.
WEBINAR 5: The New Role of Family Physicians in Times of COVID-19
The fifth webinar of the COVID-19 Series saw Prof. Dr. Christos Lionis discuss the new role of family physicians that emerged during the COVID-19 pandemic.
WEBINAR 6: Survey on Symptoms/Signs, Protective Measures, Level of Awareness and Perception Regarding COVID-19 Outbreak among Dentists
In the sixth webinar of this series, Prof. Dr. Guglielmo Campus and Prof. Dr. Maria Grazia present and discuss the risk and the preventions that can and should be taken by dentists during this pandemic.
WEBINAR 7: Living with COVID-19: An Early Intervention Therapeutic Strategy to Control the Pandemic
The seventh webinar of the COVID-19 series, Dr. Hamid Merchant discussed the different therapeutic strategies that can be adopted in the early stages of the infection.
WEBINAR 8: Impact of COVID-19 on Routine Immunization, Reproduction and Pregnancy Outcome
For the eighth COVID-19 webinar, Prof. Dr. Jon Øyvind Odland discussed the effect that COVID-19 seems to have on pregnant women; whereas Prof. Dr. Giovanni Gabutti discussed the role of routine immunization as a way of fighting COVID-19.
