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Background/Objectives: Public healthcare workers face significant occupational stress during crisis situations, yet research on this particular population remains limited compared to other healthcare workers. The aim of this study was to investigate the impact of the COVID-19 pandemic on distress levels and the
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Background/Objectives: Public healthcare workers face significant occupational stress during crisis situations, yet research on this particular population remains limited compared to other healthcare workers. The aim of this study was to investigate the impact of the COVID-19 pandemic on distress levels and the sense of coherence among public health workers by integrating psychological assessments with physiological markers of stress to identify protective factors against pandemic-related occupational stress. Methods: This longitudinal study was conducted at the Teaching Public Health Institute of Split and Dalmatia County from July 2021 to February 2022 at two time points: the latency phase (between COVID-19 waves) and hyperarousal phase (during an active wave). Fifty-four public health workers participated in the study. There were three questionnaires assessing psychological distress: Kessler Psychological Distress Scale, Impact of Events Scale—Revised and Sense of Coherence Scale-29. Salivary and blood samples were collected at both time points to measure cortisol levels, cortisol awakening response, and interleukin-6 concentrations. Results: The cortisol area under the curve with respect to ground (AUCg) was significantly elevated during the stress phase compared to the latency phase (234.8 vs. 201.8; p = 0.023), indicating heightened physiological stress responses. Epidemiologists demonstrated significantly lower sense of coherence scores compared to non-epidemiologists (117.9 ± 9.1 vs. 125.6 ± 10.5; p = 0.029). A lower sense of coherence was significantly associated with higher psychological distress and post-traumatic stress symptoms. Multiple linear regression analysis revealed that sense of coherence and interleukin-6 levels were significant independent predictors of cortisol changes. Conclusions: The findings demonstrate that public health workers experience measurable physiological stress responses during pandemic peaks, with sense of coherence emerging as a protective psychological factor. Interventions targeting sense of coherence and organizational support may possibly enhance resilience and reduce mental health morbidity in this vulnerable workforce during crisis situations.
Full article
Background/Objectives: Post-COVID-19 pulmonary fibrosis (PCPF) and idiopathic pulmonary fibrosis (IPF) exhibit significant clinical and pathophysiological overlap, suggesting convergent molecular pathways driving fibrosis. This prospective longitudinal study investigates the sustained dysregulation of matrix metalloproteinases (MMP)-2 and MMP-9 and its relationship with evolving systemic
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Background/Objectives: Post-COVID-19 pulmonary fibrosis (PCPF) and idiopathic pulmonary fibrosis (IPF) exhibit significant clinical and pathophysiological overlap, suggesting convergent molecular pathways driving fibrosis. This prospective longitudinal study investigates the sustained dysregulation of matrix metalloproteinases (MMP)-2 and MMP-9 and its relationship with evolving systemic inflammation and endothelial dysfunction in convalescent COVID-19 patients, with comparative analysis to IPF. Methods: We conducted a prospective observational study of 86 patients at 6 and 12 months post-SARS-CoV-2 infection, stratified by high-resolution CT evidence of PCPF (FB+ group, n = 32) or absence of fibrosis (FB− group, n = 54). Gene expression of MMP-2 and MMP-9 in peripheral blood leukocytes and circulating levels of MMP-2, MMP-9, pro-inflammatory cytokines (TNF-α, IL-6), and endothelial dysfunction markers (Endothelin-1 [ET-1], adhesion molecules) were quantified via qRT-PCR and ELISA. A pre-pandemic healthy control group (HD, n = 20) and an IPF patient group (n = 10) served as comparators. Results: A significant, sustained elevation of MMP-2 and MMP-9 was observed in all post-COVID-19 patients versus HDs, most pronounced in the FB+ group and qualitatively similar to IPF. A critical divergence emerged: FB− patients showed resolution of systemic inflammation (reduced TNF-α, IL-6), whereas FB+ patients exhibited persistent cytokine elevation. Critically, a delayed, severe endothelial dysfunction, characterized by a profound surge in ET-1 and elevated adhesion molecules, manifested exclusively in the FB+ cohort at 12 months. Positive correlations linked plasma MMP-2/9 levels with ET-1 (rs = 0.65, p = 0.004; rs = 0.49, p = 0.009) and ET-1 with sICAM-1 (rs = 0.68, p = 0.01). Conclusions: The development of PCPF is associated with a distinct pathogenic triad: sustained MMP dysregulation, failure to resolve inflammation, and severe late-phase endothelial dysfunction. The correlative links between these components suggest a self-reinforcing loop. This systemic signature mirrors patterns in IPF, underscoring shared final pathways in fibrotic lung disease and identifying the MMP–inflammation–endothelial axis as a promising target for biomarker development and therapeutic intervention.
Full article
Excess commuting reflects the inefficiency of urban land resource allocation, generating additional greenhouse gas emissions and social costs, and has therefore become a central concern in the pursuit of sustainable cities. While exogenous shocks inevitably alter the efficiency of land resource allocation, it
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Excess commuting reflects the inefficiency of urban land resource allocation, generating additional greenhouse gas emissions and social costs, and has therefore become a central concern in the pursuit of sustainable cities. While exogenous shocks inevitably alter the efficiency of land resource allocation, it remains unclear how such shocks affect overall urban efficiency. To address this gap, this paper proposes a generalized framework for measuring excess commuting that accounts for imbalances between the numbers of jobs and residences. Drawing on mobile signaling big data, we trace the daily commuting patterns of more than 900,000 residents in Beijing, comparing the pre-pandemic period (March–October 2019) with the pandemic period (March–October 2020). The results show that: (1) Excess commuting increased significantly after the outbreak of COVID-19, with the observed average commuting distance (Tact) of the full sample rising from 6267 m to 10,058 m (an increase of 59%), indicating a decline in urban land resource allocation efficiency; (2) A more pronounced center-periphery pattern emerged at the metropolitan scale: the average Jobs–Housing Ratio (JHR) increased from 1.08 to 1.11, and its standard deviation rose from 0.54 to 0.70, with the JHR of central urban areas decreasing by 3% and that of suburban areas increasing by 20%—suggesting a marked increase in commuting distances; (3) Heterogeneous impacts were observed across age groups: the Difference-in-Differences (DID) regression confirmed a significant negative interaction term (Group × COVID-19 = −0.2991 **, p < 0.05), indicating that older adults experienced a greater increase in commuting inefficiency than younger adults. These findings reveal the dynamic mechanisms linking exogenous shocks, jobs–housing mismatch, and urban land resource allocation efficiency and provide policy implications for improving spatial resource allocation in the post-pandemic era.
Full article
Long COVID (LC) may involve endocrine dysfunction; however, the underlying mechanism remains unclear. To examine hypothalamic–pituitary responses in patients with LC, we conducted a single-center retrospective study of patients with refractory LC referred to our University Hospital who underwent anterior pituitary stimulation tests.
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Long COVID (LC) may involve endocrine dysfunction; however, the underlying mechanism remains unclear. To examine hypothalamic–pituitary responses in patients with LC, we conducted a single-center retrospective study of patients with refractory LC referred to our University Hospital who underwent anterior pituitary stimulation tests. Between February 2021 and November 2025, 1251 patients with long COVID were evaluated, of whom 207 (19%) had relatively low random ACTH or cortisol levels. Ultimately, 16 underwent anterior pituitary stimulation tests and were included. All tests were performed in an inpatient setting without exogenous steroids. Fifteen patients (six women, mean age 35.6 years) underwent corticotropin-releasing hormone (CRH), thyrotropin-releasing hormone (TRH), and gonadotropin-releasing hormone (GnRH) tests. All patients had mild acute COVID-19, eight had ≥2 vaccinations, and the mean interval from infection was 343 days. Frequent symptoms included fatigue (100%), insomnia (66.7%), headache (60.0%), anorexia/nausea (40.0%), and brain fog (40.0%). Mean early-morning cortisol and 24 h urinary free cortisol were 7.5 μg/dL and 41.0 μg/day, respectively. MRI showed an empty sella in one case. Peak hormonal responses were preserved (ΔACTH 247%, ΔTSH 918%, ΔPRL 820%, ΔFSH 187%, ΔLH 1150%); however, peaks were delayed beyond 60 min in ACTH (13%), LH (33%), and FSH (87%). Notably, significantly delayed elevations remained at 120 min in the responses of TSH (4.1-fold), PRL (1.8-fold), LH (9.3-fold), and FSH (2.8-fold), suggesting possible hypothalamic involvement, particularly in the gonadotropin responses. Additionally, serum IGF-I was lowered (−0.70 SD), while GH response (mean peak 35.5 ng/mL) was preserved by growth hormone-releasing peptide (GHRP)-2 stimulation. Low-dose hydrocortisone and testosterone were initiated for three patients. Although direct viral effects and secondary suppression have been proposed, our findings may suggest that, at least in part, the observed response characteristics are consistent with functional secondary hypothalamic dysfunction rather than irreversible primary injury. These findings highlight the need for objective endocrine evaluation before initiating hormone replacements.
Full article
by
Filippo Domma, Luca Soraci, Ersilia Paparazzo, Ilaria Amerise, Mirella Aurora Aceto, Teresa Serra Cassano, Dina Bellizzi, Salvatore Claudio Cosimo, Francesco Morelli, Andrea Corsonello, Giuseppe Passarino and Alberto Montesanto
Vaccination has been a cornerstone of the public health response to the COVID-19 pandemic, particularly in protecting older and frail populations. A detailed characterization of antibody titer dynamics and their determinants represents a crucial step toward optimizing vaccination strategies. However, antibody titers are
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Vaccination has been a cornerstone of the public health response to the COVID-19 pandemic, particularly in protecting older and frail populations. A detailed characterization of antibody titer dynamics and their determinants represents a crucial step toward optimizing vaccination strategies. However, antibody titers are bounded within assay-specific limited intervals and often display skewness and intra-subject correlation, which limit the suitability of conventional modeling approaches. We analyzed longitudinal antibody titer data from 608 residents and staff members of five nursing homes in Calabria (southern Italy) using beta-generalized linear mixed models (β-GLMMs). This framework enabled simultaneous modeling of the mean humoral response (μ), precision parameter (ϕ), and probability of achieving the maximum immune response (α), thereby providing a comprehensive assessment of factors influencing immune dynamics. Two distinct patterns of antibody titer evolution were identified. Among nursing home residents, stroke was associated with higher antibody concentrations, whereas atrial fibrillation, lower body mass index, non-Alzheimer’s dementia, and chronic obstructive pulmonary disease were linked to reduced responses. The β-GLMM approach allowed for a more accurate identification of demographic and clinical determinants compared with traditional methods. These findings underscore the utility of β-GLMMs for analyzing bounded longitudinal immunological data and highlight key factors shaping vaccine-induced immunity. Such insights may lead to more tailored immunization strategies in vulnerable older populations.
Full article
The reliance on unstable hydrogen peroxide (H2O2) adversely affects the robustness and simplicity of chemiluminescence (CL)-based immunoassays. We report a novel external H2O2-free Fenton CL system integrated into a highly sensitive non-enzymatic immunoassay for the
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The reliance on unstable hydrogen peroxide (H2O2) adversely affects the robustness and simplicity of chemiluminescence (CL)-based immunoassays. We report a novel external H2O2-free Fenton CL system integrated into a highly sensitive non-enzymatic immunoassay for the detection of SARS-CoV-2 nucleoprotein, utilizing cuprous–polyethylenimine–lipoic acid nanoflowers (Cu(I)-PEI-LA-Ab NF) as a non-enzymatic tag. The signaling polymer (PEI-LA) was synthesized via EDC/NHS coupling, which conjugated approximately 550 LA units to the PEI backbone. This polymer formed antibody-conjugated NF with various metal ions, and the Cu(I)-based variant was selected for its intense and sustained CL with luminol. The mechanism relies on an in situ Fenton reaction, in which dissolved oxygen is reduced by Cu(I) to H2O2, which reacts with oxidized Cu(II), producing hydroxyl radicals that oxidize luminol. Direct calibration of the SARS-CoV-2 nucleoprotein fixed on microplate wells demonstrated excellent linearity in the range of 0.01–3.13 ng/mL (LOD = 3 pg/mL). In a final competitive immunoassay format for samples spiked with the antigen, a decreasing CL signal that correlated with increasing antigen concentration was obtained in the range of 0.1–20.0 ng/mL, achieving excellent recoveries that were favorable compared with those of the sandwich ELISA kit, establishing this H2O2-independent platform as a powerful and robust tool for clinical diagnostics.
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.
