Search Results (6,145)

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and long COVID-19 syndrome (LC) show substantial clinical overlap, but direct comparative microbiome studies remain limited. Methods: In this cross-sectional study, we compared the fecal gut microbiome of patients with ME/CFS, LC, and healthy controls (HC) within a unified analytical framework using 16S rRNA profiling, differential abundance testing, and multivariate modeling. We also examined associations between microbiome variation and questionnaire-derived symptom-domain scores. Results: Alpha-diversity did not differ significantly among groups, whereas beta-diversity analyses showed small but significant disease-associated community differences with broad overlap between cohorts. Differential abundance analysis identified stronger signals in disease-versus-control contrasts than in the direct ME/CFS vs. LC contrast. Both ME/CFS and LC shared enrichment of Sutterella and depletion of Terrisporobacter and Lachnospiraceae relative to HC. Predicted functional profiling showed shared disease-versus-control changes in pathways related to anaerobic acetate/H₂ carbon flow, inositol/polyol degradation, phosphonate/C1-related metabolism, and lysine-derived fermentation. Regression analyses showed the strongest microbiome associations with fatigue-related and physiosomatic domains, while affective, cognitive, and gastrointestinal outcomes showed weaker signals. Conclusions: Overall, these findings support the presence of overlapping but non-identical gut microbiome alterations in ME/CFS and LC. The results provide a basis for future longitudinal and multi-omics studies aimed at clarifying the stability, functional relevance, and clinical utility of these microbial patterns. Full article

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has greatly impacted public health due to high rates of transmissibility and mutation during the COVID-19 pandemic. Macrodomain 1 (Mac1) of non-structural protein 3 remained well conserved across variants and is critical to suppression of host immune response to infection, making Mac1 a promising target for therapeutic development. Mac1 binds and cleaves the post-translational modification ADP-ribose and is hypothesized to have a downstream effect on the host interferon response, but the exact cellular targets of Mac1 are still unknown. Characterizing the substrates of Mac1 ADP-ribosyl hydrolase activity using a catalytically inactive mutant N40D can reveal critical virus–host interactions to identify protein targets of Mac1 and reveal mechanisms of host interferon suppression. Here, we performed affinity enrichment with WT Mac1 and Mac1 N40D in HEK293T and A549 cells and quantified changes in protein interactions by TMT-multiplexed tandem mass spectrometry. We identified interactions between Mac1 and ADP-ribosylated substrates involved in DNA damage response, cytoskeletal components, and cell cycle regulation. Additionally, several members of the TRiC complex involved in protein folding were selectively enriched with mutant Mac1 from A549 cells. These findings suggest a novel role of Mac1 in regulating host protein folding. Full article

Background: Wastewater-based surveillance (WBS) has emerged as a valuable tool for population-level monitoring of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) transmission, yet the interplay between sampling strategies and disease prevalence in shaping detection performance remains ambiguous. We investigated how grab and composite sampling influence SARS-CoV-2 ribonucleic acid (RNA) detection dynamics and predictive lag times across high- and low-prevalence communities in Selangor, Malaysia. Methods: A 28-week longitudinal study was conducted in Selangor, Malaysia, comparing grab and composite wastewater sampling in communities with high and low Coronavirus disease 2019 (COVID-19) prevalence. SARS-CoV-2 RNA in 348 samples was quantified using digital Reverse Transcription Polymerase Chain Reaction (RT-dPCR), and viral lineages were characterized by Nanopore sequencing. Detection sensitivity and lead times relative to reported cases were evaluated. Results: In low-prevalence settings, grab sampling showed higher detection sensitivity than composite sampling (92.0% vs. 70.0%), whereas both methods achieved similarly high detection in high-prevalence areas (>97.0%). Lag-time analysis indicated that grab sampling in high-prevalence settings was significantly associated with case trends at potential two-week lead (p = 0.024), while composite sampling in low-prevalence settings showed the strongest association at a potential one-week lead (p = 0.0022). Overall, lag structures varied by both sampling strategy and prevalence context. Both sampling approaches captured the replacement of Omicron sublineages (XBB.1.5, XBB.1.9.1, XBB.1.16) and identified additional circulating variants, including EG.5, that were not captured in the available clinical sequencing dataset during the same period. Conclusions: These findings reveal that local transmission intensity is associated with the utility of different sampling designs. Context-specific optimization of WBS sampling strategies enhances sensitivity, reduces detection lag, and strengthens early warning and genomic-tracking capacity in public health surveillance frameworks. Full article

Background: Non-invasive respiratory supports (High-Flow Nasal Oxygen, HFNO; Continuous Positive Airway Pressure, CPAP; Non-Invasive Ventilation, NIV) are frequently used in Acute Hypoxemic Respiratory Failure (AHRF). However, the experience of assisted breathing may profoundly affect patients’ psychological balance, particularly during acute critical illness and subsequent rehabilitation. Aims and objectives: This longitudinal study investigated the psychological burden associated with non-invasive respiratory support use in patients with COVID-19-related AHRF, exploring changes in psychological functioning from acute hospitalization (RICU/ICU) (T0) to follow-up, conducted at a mean of 6.0 ± 3.1 months after respiratory rehabilitation (T1). Methods: Fifty-two patients (mean age = 66.9 ± 9.17 years) were assessed at T0 and T1. Standardized measures evaluated anxiety, psychological distress, post-traumatic stress symptoms, depression, and resilience, in relation to perceived illness severity and subjective experience of non-invasive respiratory support. Results: During acute care, patients reported high levels of fear and anxiety related to illness severity and uncertainty. The experience of non-invasive respiratory support, often perceived as a marker of critical condition, was associated with increased fear and anxiety (t(14) = 2.79, p = 0.014) compared to the recovery phase, leading to feelings of loss of control and diminished psychological well-being (t(17) = 2.35, p = 0.031). However, resilience significantly improved over time (t(16) = −4.78, p < 0.001). Conclusions: Non-invasive respiratory support may represent a psychologically demanding experience, often perceived as challenging to patients’ sense of safety and control. Encouragingly, psychological adaptation and resilience can improve during rehabilitation. Integrating structured psychological support within respiratory rehabilitation pathways may promote recovery and restore psychological balance in patients requiring assisted ventilation. Full article

Background/Objectives: The hepatitis A virus (HAV) infection continues to represent a considerable public health issue in Eastern Europe, particularly in Bulgaria, where incidence rates exceed the EU average. This study sought to investigate the epidemiological and clinical aspects of acute hepatitis A in Southern Bulgaria between 2015 and 2023 and to assess changes during the COVID-19 pandemic period. Methods: A retrospective descriptive-analytic study was conducted among 1810 hospitalized patients with confirmed acute HAV infection at a tertiary infectious diseases center from 2015 to 2023. Demographic, clinical, laboratory, and temporal data were analyzed, comparing the pre-pandemic period (2015–2019) with the pandemic phase (2020–2023). Results: Most hospitalized cases occurred during the pre-pandemic period (88.0%), with epidemic peaks observed in 2016–2017. Individuals under 18 years comprised 69.9% of cases, with a median age of 9 years and a slight male predominance of 54.9%. A notable seasonal pattern was identified, characterized by peaks in autumn and early winter. Patients hospitalized during the pandemic period were significantly older compared with the pre-pandemic period (median age 14 vs. 8 years, p < 0.001). Adults experienced significantly longer hospitalization and higher ALT, AST, total bilirubin, and direct bilirubin levels compared with pediatric patients (all p < 0.001). The median duration of hospitalization was 7 days (IQR 6–10). Two in-hospital deaths were recorded, corresponding to a case fatality rate of 0.11%. Conclusions: Hepatitis A in Southern Bulgaria mostly impacts children but exhibits changing epidemiological trends, underscoring the necessity for focused preventative methods, such as vaccination and enhanced surveillance. Full article

Background: The relationship between allergic status, SARS-CoV-2 infection, Long COVID, and post-restriction respiratory outcomes in children remains incompletely understood. This study aimed to explore the associations between allergic status and Long COVID, as well as between SARS-CoV-2 vaccination and post-restriction changes in allergic rhinitis (AR), asthma, and upper respiratory infections, in a pediatric tertiary-care cohort. Methods: We conducted a single-center, questionnaire-based observational study involving children aged 0–16 years, who were followed at the Pediatric Allergy Clinic of Umberto I Hospital in Rome. Parents completed an email-based questionnaire addressing SARS-CoV-2 infection, vaccination, persistent post-infectious symptoms, allergic diseases, and respiratory infections following restrictions. Analyses of Long COVID were limited to children with confirmed SARS-CoV-2 infection. Results: A total of 214 questionnaires were analyzed. Allergic status was not significantly associated with SARS-CoV-2 infection in the overall cohort. Among infected children, allergic status was independently associated with higher odds of Long COVID (adjusted OR 3.12, 95% CI 1.20–8.09; p = 0.019). Severe acute infection was also strongly associated with Long COVID (adjusted OR 6.84, 95% CI 2.72–17.21; p < 0.001). Complete vaccination was associated with lower odds of SARS-CoV-2 infection in the overall sample (adjusted OR 0.20, 95% CI 0.09–0.46; p < 0.001) but was not independently associated with Long COVID among infected children. After the removal of COVID-19 restrictions, 90.1% of allergic children reported worsening AR and 52.0% reported worsening asthma, with no significant association with SARS-CoV-2 infection or Long COVID. Group A Streptocossus (GAS) pharyngitis was reported in 50.0% and viral pharyngitis in 10.7% of the cohort, with no significant differences between allergic and non-allergic children. Conclusions: In this single-center, questionnaire-based pediatric cohort, allergic status was correlated with increased likelihood of Long COVID among children with confirmed SARS-CoV-2 infection; however, it was not associated with a higher risk of infection itself. Complete vaccination was linked to a reduced risk of infection, whereas no independent correlation with Long COVID was identified. Post-restriction exacerbation of allergic respiratory symptoms was prevalent, while the incidence of bacterial and viral pharyngitis did not vary significantly according to allergic status. Full article

Global crises often force a pivotal choice between protecting human legacy and ensuring financial survival, yet the psychological drivers behind these trade-offs remain poorly understood. While family firms are traditionally viewed as inherently resilient, the unique emotional attachments of their owners may constrain their ability to adapt to unprecedented shocks. This study examines the behavioral underpinnings of crisis management across 11 European nations during the COVID-19 pandemic, challenging the traditional stewardship paradigm. Findings reveal a significant tension between preserving socioemotional wealth and economic survival. While family-managed firms prioritized personnel retention and financial autonomy, thus avoiding the psychological stigma of government aid, these non-financial priorities often proved detrimental to liquidity and business survival. This suggests that high emotional endowment can induce behavioral rigidity and an escalation of commitment, hindering strategic pivots. Furthermore, the results highlight a trend toward mimetic isomorphism, where extreme uncertainty forced a convergence of crisis responses across diverse organizational structures. Overall, the contribution of this study is to challenge the resilience myth, illustrating that acute shocks often override the distinctive behavioral archetype of family firms, forcing a shift toward institutional conformity and standardized mandates. Full article

Severe COVID-19 is characterized by profound thromboinflammatory and immune disturbances, but the network-level relationships among complement–coagulation dysregulation, humoral immune remodeling, and iron-associated immune regulation remain incompletely understood. Here, we performed integrative proteomic and transcriptomic analyses across peripheral blood and lung microenvironments using weighted gene co-expression network analysis (WGCNA), differential network analysis (DiNA), and immune deconvolution. Proteomic network analysis identified a disease-associated module enriched in complement activation, coagulation cascades, platelet degranulation, and acute inflammatory responses. Hub proteins, including C9, LBP, vWF, and F11, were prioritized based on module association and intramodular connectivity. Notably, C9 and LBP were repeatedly identified across WGCNA, DiNA, and differential expression analyses, underscoring their robust association with severe COVID-19-associated molecular network remodeling. Transcriptomic and CIBERSORTx-based immune deconvolution analyses showed altered immune-cell composition in blood and lung tissues, including B-cell and plasma-cell-associated changes. Notably, TFRC displayed cell-type-associated expression changes in naïve B cells and plasma cells, suggesting a potential link between iron-associated immune regulation and humoral immune remodeling. Collectively, these computational findings highlight coordinated complement–coagulation dysregulation, humoral immune remodeling, and TFRC-associated iron-related immune alterations in severe COVID-19, and prioritize TFRC, C9, and LBP as candidate molecular indicators requiring further experimental and clinical validation. Full article

Background: Severe asthma exacerbations remain a major cause of pediatric intensive care unit (PICU) admissions, particularly in early childhood. Objective: To describe the demographic characteristics, clinical features, management strategies, and short-term outcomes of children admitted to the PICU with severe acute asthma exacerbations. Methods: A retrospective descriptive study was conducted of pediatric patients aged 1–14 years with severe acute asthma requiring PICU admission at King Salman Medical City, Madinah, Saudi Arabia (January 2023–October 2024). A total of 73 patients were included. Data included demographics, risk factors, medical history, clinical presentation, management, and outcomes. Results: The mean patient age was 4.6 years, with most (57.5%) aged 1–5 years. Males comprised 56.2% of cases. WHO BMI-for-age z-score assessment revealed a bimodal nutritional distribution: 27.9% of patients were underweight, including 20.6% with severe underweight, while 29.4% were overweight or obese; 42.6% had normal nutritional status. Severe undernutrition was concentrated in the 1–5-year age group, whereas obesity predominated in the 6–10-year age group. A family history of asthma was noted in 54.8% of patients; 16.4% had prior COVID-19 infection. Early symptom onset and delayed diagnosis were common. Poor asthma control was documented in 60.3%, with low medication adherence (9.6%) and limited aerochamber use (13.7%). The most frequent presenting symptoms were dyspnea, cough, and wheezing. Management followed evidence-based protocols: systemic corticosteroids and bronchodilators were first-line therapies. The mean PICU stay was 3.1 days and the mean hospital stay was 8.1 days. No mortality or major complications occurred; 93.2% of patients were discharged in good health. Conclusions: Severe pediatric asthma requiring PICU admission is associated with early symptom onset, a bimodal pattern of nutritional risk encompassing both undernutrition and overweight/obesity, family history of asthma, and inadequate outpatient management. These descriptive findings highlight the need for age-adjusted nutritional screening, enhanced medication adherence support, and targeted outpatient education to reduce avoidable PICU admissions. Full article

Background/Objectives: Epidemiological studies over the first decades of the 21st century have reported a decrease in cardiovascular disease (CVD) morbidity and mortality. Changes in coronary care for acute myocardial infarction (AMI) over these years, including the COVID-19 pandemic period, have been less studied in Eastern and Central Europe. The study aimed to assess changes in coronary care—the time of medical assistance and treatment—for AMI patients over 2000–2023 in urban Kaunas residents aged 25–64. Methods: The data source was study cases from the Kaunas Ischemic Heart Disease Registry (Registry)—Kaunas city residents aged 25–64 years included in the Registry according to MONICA project protocol evaluation methodologies. Data were analyzed by sex and age group (25–54 and 55–64 years). Descriptive statistics (chi-square and z-score values) were used to evaluate the data; the significance level was p < 0.05. A logistic regression analysis was performed to assess the odds ratios of death within 28 days across six time periods. Results: The proportion of AMI patients hospitalized up to 2 h from the onset of pain accounted for about one-fifth of all hospitalized patients in 2000–2016, while in 2017–2023, it significantly decreased. In 2017–2023, compared with 2000–2004 and 2009–2016, significantly fewer men who developed AMI were hospitalized within the first 2 h of emergency presentation (p < 0.05). Over the whole study period, fewer women with AMI were hospitalized within the first 2 h of pain as compared to men (p < 0.05). There were no significant differences in time from pain onset to hospitalization between the age groups. At the same time, from 2009 to 2012, more young AMI patients were hospitalized within the first 2 h (p < 0.05). Percutaneous coronary angioplasty (PTCA) with stenting (PCI) increased 30 times from 2000–2004 to 2020–2023. PCI has been the most available treatment for men with AMI since 2009 and stayed stable from 2013 (66.0%) until 2023 (72.1%). Women with AMI tended to get less PCI, PTCA, and coronary artery bypass grafting (CABG) than men. The pre-pandemic and COVID-19 periods did not differ in the proportions of reperfusion treatment methods used in both men and women. Thrombolysis was very rare, and since 2017, it has not been used in Kaunas because PCI has become more accessible. PCI (2000–2016) and CABG (2009–2016) were more prevalent among the 25–54-year-old AMI patients (p < 0.05). From 2017 to 2023, there were no differences between age groups in the reperfusion procedures used, nor were there differences in treatment between these groups during the pre-pandemic (2017–2019) and peri-COVID-19 pandemic (2020–2023) periods. Conclusions: In Kaunas, the treatment of patients with AMI has improved significantly over the past 20 years. The use of PCI has increased greatly, and the rate of CABG surgery stayed stable, while only every fifth patient has been admitted to the hospital in a timely manner. Men were more likely to receive PCI, and older patients were more likely to undergo CABG. Compared to the period of 2000–2004, the chance of dying within 28 days after AMI was significantly lower in 2017. Full article

Background/Objectives: The COVID-19 pandemic has raised concerns about maternal mental health, particularly among women infected during pregnancy. This study aimed to examine longitudinal changes in depressive and anxiety symptoms and subjective distress among pregnant women in Slovakia with confirmed SARS-CoV-2 infection and to explore the role of obstetric complications and vaccination status in these trajectories. Methods: In this retrospective longitudinal study, women with SARS-CoV-2 infection during pregnancy were assessed at three time points: during infection, six weeks postpartum, and one year postpartum (11 March 2020–5 May 2023). Depressive symptoms were measured using the Edinburgh Postnatal Depression Scale (EPDS; cut-off ≥ 11), anxiety symptoms were measured using the EPDS-3A subscale (cut-off ≥ 5), and subjective distress was measured using visual analogue scales (VAS). A repeated-measures ANCOVA design was used to evaluate within-subject changes over time while adjusting for vaccination status and pregnancy complications. Results: Of 1184 contacted women, 170 provided complete data. The proportion of women exceeding the EPDS cut-off decreased from 27.6% during infection to 17.6% at six weeks postpartum and 4.7% at one year postpartum. Anxiety symptoms showed a similar pattern, declining from 27.6% during infection to 20.6% at six weeks postpartum and 7.6% at one year postpartum. Repeated-measures analyses confirmed significant time effects across psychological outcomes, with symptom levels decreasing over the postpartum year. Post-infection obstetric complications were associated with higher subjective distress at selected time points. Conclusions: Psychological symptoms were highest during the acute infection period and declined significantly over time. These findings support the importance of timely mental health screening during pregnancy affected by COVID-19, while suggesting that, in many women, psychological distress may decrease across the postpartum year. Full article

This study examined alterations in serum redox biomarkers before and one month after administration of the coronavirus disease 2019 (COVID-19) booster (third) doses across four vaccine regimens. A longitudinal cohort of 410 adults was analyzed following homologous Pfizer-BioNTech, Sinopharm [Vero Cell]-Inactivated, Sputnik V, or heterologous Sinopharm/Pfizer vaccination. Serum total proteins, albumin, total thiols, nitrites, ferric-reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity were measured, with DPPH interpreted as an ex vivo surrogate of serum radical-scavenging capacity. Additional analyses included stratification by prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, multivariable regression, correlation analysis, effect-size estimation, and sensitivity testing. Booster vaccination was associated with modest but consistent decreases in DPPH activity, albumin, and total proteins, whereas FRAP, nitrite, and total thiol levels remained stable. This pattern supports a transient shift in antioxidant buffering capacity but, by itself, does not exclude oxidative stress, as direct oxidative damage markers were not assessed. The most pronounced changes were observed in Sinopharm-based regimens, particularly in the heterologous Sinopharm/Pfizer group. Prior SARS-CoV-2 infection did not materially alter the qualitative response pattern, whereas older age and comorbidities were associated with greater declines in DPPH activity and albumin. Overall, the findings indicate a modest, transient redox-associated response following booster-induced immune activation and suggest that host-related factors, such as age and comorbidity burden, may accentuate short-term changes in antioxidant buffering capacity. Full article

Background and Objectives: Healthcare-associated infections (HAIs) remain a major cause of morbidity and mortality among hospitalized patients. During the COVID-19 pandemic, SARS-CoV-2 infection emerged as a major contributor to HAIs, alongside Clostridioides difficile infection (CDI) and other bacterial infections. This study aimed to evaluate the clinical characteristics and outcomes of HAIs in surgical departments and to identify factors associated with in-hospital mortality. Materials and Methods: We conducted a retrospective observational study including 170 patients with documented HAIs admitted between July 2018 and June 2022 in surgical departments of a county emergency hospital. Patients were categorized into SARS-CoV-2 infection (n = 85), CDI (n = 73), and other bacterial infections (n = 12), the latter being included for descriptive purposes only due to limited sample size. Clinical variables, comorbidities, prior antibiotic exposure, length of hospital stay, and in-hospital mortality were analyzed. Survival analysis and logistic regression were performed to identify predictors of mortality. Results: SARS-CoV-2 infection represented the largest subgroup, followed by CDI. Overall, in-hospital mortality was 15.9%, with comparable rates between SARS-CoV-2 infection (17.6%) and CDI (16.4%), while no deaths were observed in the small subgroup of other bacterial infections. CDI patients had a significantly higher burden of comorbidities (p = 0.004). Kaplan–Meier analysis did not show a statistically significant difference in survival between SARS-CoV-2 and CDI groups (log-rank p = 0.28). In univariate analysis, acute respiratory failure (OR ≈ 13.5, p < 0.001), chronic kidney disease (OR ≈ 4.4, p = 0.018), and number of comorbidities (p = 0.019) were associated with mortality, but none remained significant in multivariable analysis. Conclusions: In-hospital mortality was similar between SARS-CoV-2 infection and CDI, highlighting the persistent clinical impact of CDI in hospitalized patients. Comorbidity burden and acute complications, particularly respiratory failure, were key determinants of mortality. These findings highlight the persistent clinical impact of CDI and the role of comorbidity burden and acute complications, particularly respiratory failure, in shaping in-hospital mortality. The absence of independent predictors in multivariable analysis should be interpreted cautiously given the limited sample size. Full article

Background: During the COVID pandemic increased rates of intensive care unit (ICU) admission, mechanical ventilation, caesarean delivery, and preterm birth among women with SARS-CoV-2 infection in pregnancy were recorded. Purpose: This study describes the clinical course and perinatal outcomes of pregnant women with COVID-19 across pre- and post-vaccination periods. Methods: This study included all pregnant women with confirmed SARS-CoV-2 infection who subsequently delivered at the University General Hospital of Larissa between March 2020 and May 2023. Demographics, comorbidities, gestational age at infection and at delivery, COVID-19 symptoms, need for hospitalization, obstetric complications, mode of delivery, and neonatal outcomes were documented. An assessment of ischemia-modified albumin (IMA) was performed in a subset of women. Results: A total of 327 women (including 14 twin gestations) were recorded. Most women experienced mild disease while a minority required hospital admission, or intensive care (1.8 and 0.3% for the studied population, respectively). Fever and upper respiratory symptoms predominated, while radiologic evidence of pneumonia was rare. Overall preterm birth (<37 weeks) occurred in 13% of pregnancies and caesarean section in about two thirds of deliveries. Neonatal outcomes were favorable, with low rates of neonatal intensive care unit (NICU) admission and no early neonatal deaths. IMA values were higher during acute infection and declined towards recovery. Conclusion: Pregnant women with COVID-19 in Central Greece had predominantly mild clinical courses and excellent perinatal outcomes. IMA may represent a biologically plausible marker of disease activity, but further studies are needed. Full article

Evidence on hospitalised COVID-19 patients during the Omicron BA.5 wave from Eastern European, vaccine-heterogeneous cohorts remains limited. We conducted a retrospective single-centre cohort study of 395 consecutive adults admitted with laboratory-confirmed COVID-19 to a tertiary infectious-diseases unit in western Romania between 1 July and 31 October 2022. Median age was 72 years (IQR 65–81); 33.2% were unvaccinated, 42.8% had documented prior SARS-CoV-2 infection, and 41.3% were obese. Multivariable logistic regression identified independent predictors of in-hospital mortality and post-acute symptom burden. In-hospital mortality was 15.7% (62/395). Vaccination was independently associated with lower mortality (adjusted odds ratio [aOR] 0.55, 95% CI 0.30–0.99; p = 0.048), as was each 1% increase in admission SpO₂ (aOR 0.83, 95% CI 0.76–0.92; p < 0.001), whereas COPD independently increased mortality risk (aOR 2.42, 95% CI 1.15–5.10; p = 0.020). Interleukin-6 was the most discriminating admission biomarker for in-hospital mortality (AUROC 0.70). Bloodstream bacterial co-infection, detected in 22.5% of patients tested on clinical suspicion, was dominated by gut-derived organisms with case-fatality ≥30%. At discharge, 90.1% reported persistent symptoms, most commonly cognitive (24.6%). Prior SARS-CoV-2 infection independently predicted post-acute symptom burden (aOR 2.96, 95% CI 1.75–5.01; p < 0.001), with a specific cardiopulmonary signature. In this BA.5 cohort, vaccination remained protective; IL-6 was the most informative admission biomarker; bloodstream infections suggested gut translocation; and prior infection was an independent determinant of early post-acute symptom burden. Full article