COVID, Volume 5, Issue 8 (August 2025) – 29 articles

Background: To evaluate and compare cardiorespiratory function, assessed by the 6-minute walk test (6MWT), and musculoskeletal function, assessed by the handgrip strength test and the sit-to-stand test (STS10) in post-coronavirus disease 2019 (COVID-19) patients. Participants were stratified based on the time since infection (≤6 months and >6 months) and compared with matched healthy controls. Methods: A total of 111 participants were recruited and divided into three groups (n = 37/group). Cardiorespiratory function was assessed using the 6MWT, while musculoskeletal function was evaluated through the handgrip strength test and the STS10. Results: All three groups had normal body mass index values. Group 2 demonstrated significantly lower handgrip strength and a shorter 6MWT distance compared to both Group 1 and Group 3. Additionally, Group 2 required significantly more time to complete the STS10 than Group 1. Following the 6MWT, Group 2 exhibited significantly higher heart rate and systolic blood pressure compared to both Group 1 and Group 3. Diastolic blood pressure was significantly lower in Group 3 compared to the other two groups. Furthermore, Group 2 had significantly lower pulse oxygen saturation than both Group 1 and Group 3. The rate of perceived exertion was significantly lower in Group 1 than in Group 2. Additionally, leg fatigue was significantly lower in Group 1 compared to both Group 2 and Group 3. Conclusions: These findings highlight significant differences in physical performance and physiological responses between post-COVID-19 patients and healthy individuals, emphasizing the potential long-term effects of SARS-CoV-2 infection on cardiorespiratory and musculoskeletal function. Full article

Background: High concentrations of supplemental oxygen (FiO₂ > 0.6) are commonly used to treat acute hypoxemia in critically ill patients. However, the effects of High FiO₂ in patients with COVID-19 remain unclear, particularly regarding its impact on hypoxic pulmonary vasoconstriction (HPV) and ventilation–perfusion (V/Q) mismatch. Objective: This study aims to evaluate whether administering lower concentrations of inspired oxygen (FiO₂ < 0.6) is associated with improved outcomes—namely reduced need for mechanical ventilation and mortality—in patients with COVID-19 and severe pulmonary involvement. Methods: This retrospective observational cohort included 201 patients with confirmed COVID-19. Patients were grouped by mean FiO₂ during the first 24–48 h: High FiO₂ (≥0.60) or Low FiO₂ (<0.60). The primary outcome was the requirement for mechanical ventilation; the secondary outcome was in-hospital mortality. A composite endpoint (mechanical ventilation and in-hospital death) was also evaluated. Analyses included logistic regression and Kaplan–Meier survival with log-rank testing. Results: High FiO₂ (≥0.60) was associated with higher odds of the composite outcome (mechanical ventilation and in-hospital death). In multivariable analysis, Low FiO₂ remained associated with lower odds (adjusted OR 0.18; 95% CI 0.08–0.39; p < 0.001). Unadjusted rates were 43.1% vs. 16.1% for mechanical ventilation and 34.3% vs. 8.1% for in-hospital death (High vs. Low FiO₂; both p < 0.001). Event-free survival favored the Low FiO₂ group (log-rank p < 0.001). The model showed excellent discrimination (AUC 0.96; 95% CI 0.92–0.99). Conclusions: Higher early FiO₂ exposure was associated with worse clinical outcomes in severe COVID-19. These findings are consistent with physiological models in which excess oxygen may attenuate hypoxic pulmonary vasoconstriction and increase shunt/dead space. Prospective studies are warranted to assess causality and refine oxygen targets. Full article

Background: The lockdown and other measures for coronavirus disease 2019 (COVID-19) prevention have presented an enormous burden on healthcare systems, causing reorganization in work and lowering the number of elective hospitalizations, along with a consequent reduction in hospital-acquired infections and bacteremia. The aim of this study was to examine the influence of the COVID-19 pandemic on the diagnosis and management of infective endocarditis (IE). Methods: The study included 111 patients admitted for IE from 1 January 2017 to 31 December 2021. They were divided in two groups chronologically according to the COVID-19 pandemic: the first group consisted of patients before the pandemic (n = 85), while the second group consisted of patients during the pandemic (n = 26). Results: Before the pandemic there were 2.26 ± 1.41 cases/month with diagnosis of IE, while during the pandemic there were only 1.14 ± 1.15 cases/month (p = 0.004). IE patients during the pandemic were younger (53 [41–65] vs. 68 [52–74] years; p < 0.05). A similar number of patients underwent surgical treatment before and during COVID-19 (53% vs. 67%; p = 0.210) and 30-day mortality was comparable (28% vs. 22%; p = 0.539). Conclusion: The COVID-19 pandemic and lockdown measures have led to a reduction in the number of patients with IE, although this change did not influence management strategies and mortality. Full article

Introduction: Human metapneumovirus (HMPV), though commonly perceived as a pediatric pathogen, significantly impacts adults, yet its role in acute respiratory tract infections (ARTIs) remains underappreciated. The COVID-19 pandemic has reshaped respiratory virus epidemiology and amplified the need for comprehensive differential diagnosis. This study aimed to comprehensively investigate the prevalence, clinical characteristics, and post-COVID-19 trends of HMPV infection in adults and to elucidate its critical role in the differential diagnosis of ARTIs by distinguishing it from other common viral pathogens. Methods: This was a retrospective, multicenter study conducted across six hospitals within the Acibadem Hospitals Group in Istanbul, Turkey. Data were collected from two periods: January 2016 to January 2020 (pre-COVID-19) and January 2021 to September 2023 (post-COVID-19), excluding the peak pandemic phase (March 2020 to May 2021). Respiratory samples (sputum, BAL, nasopharyngeal/nasal/throat swabs) were analyzed using multiplex PCR (Seegene RV12-ACE), with an expanded panel including SARS-CoV-2 in the post-COVID-19 era. Demographic data, comorbidities, symptoms, hospitalization, and ICU admission rates were collected. Results: In the post-COVID-19 period, 2197 positive viral panels were recorded, an increase from 1357 in the pre-COVID period, reflecting enhanced testing. HMPV prevalence reached 9.7% post-COVID-19, making it the fourth most common respiratory virus in adults (8.7% of 644 positive adult tests), following SARS-CoV-2 (26.4%), influenza A (21.3%), and rhinovirus (17.5%). The average age of HMPV-infected adults was 52.14 years (18–90 years); 64% were female. While 52% had no comorbidities, common underlying conditions included hypertension (24%), cancer (12%), and diabetes (10%). Weakness (34%), lower respiratory symptoms (16%), and fever (12%) were frequent. A significant proportion of HMPV patients required hospitalization (34%) and ICU admission (18%), with 40% receiving antibiotics. Despite potential severity, the mortality rate was low (2.8%). No significant difference in severity was observed between HMPV monoinfection and co-infected groups (e.g., with influenza A, rhinovirus, SARS-CoV-2, parainfluenza virus 2). Conclusion: Our findings establish HMPV as a significant and increasingly prevalent respiratory pathogen among adults in Istanbul in the post-COVID-19 era. Its non-specific clinical presentation underscores the critical importance of multiplex PCR for accurate differential diagnosis, enabling appropriate patient management and antimicrobial stewardship. While HMPV can lead to severe outcomes requiring hospitalization and ICU admission, particularly in patients with comorbidities, the overall mortality rate remains low. Given the lack of specific antiviral treatments and vaccines, sustained surveillance and continued research into targeted interventions are crucial. Full article

Long COVID is characterized by persistent symptoms affecting one or more organ systems for at least 3 months following a SARS-CoV-2 infection. Our study aimed to examine the characteristics of frailty seen in patients with Long COVID compared to the frailty seen in aging patients with multimorbidity. This is a retrospective cohort study conducted in the Miami Veterans Affairs Medical Center (VAMC). The data used to calculate the Fried phenotype through the Johns Hopkins frailty calculator was collected from two separate clinics, a Long COVID clinic and a geriatric frailty clinic. We obtained the VA Frailty Index from VA CDW (Corporate Data Warehouse). We included 106 patients from the Long COVID clinic and 97 from the frailty clinic. Patients from the Long COVID clinic were significantly younger than those from the frailty clinic (60 ± 12.6 vs. 79.8 ± 5.8, p < 0.01). Patients with frailty in the Long COVID group experienced exhaustion (96.4% vs. 53.3%) and low activity (78.6% vs. 63.3%) at a higher rate than those in the geriatric frailty clinic. Long COVID may predispose patients to develop frailty that presents with a higher frequency of exhaustion and low activity. Full article

SARS-CoV-2 infection can be followed by prolonged symptoms, signs and sequelae, collectively known under the term Long COVID. Hundreds of millions are estimated to suffer from Long COVID. Long COVID, therefore, is a public health crisis that deserves the utmost urgency from all relevant stakeholders, from policymakers to advocacy groups, researchers and healthcare providers. The development of effective definitions and guidelines for Long COVID is crucial to support patients and carers. In this review, I address the following two case definitions of Long COVID developed in the US as a case study for a broader discussion on the sequelae of SARS-CoV-2 infection: the U.S. Government (USG) working definition for Long COVID and the NASEM definition published in 2024. In the first part of this review, I provide a critical appraisal of the USG in light of research, pathophysiology and lived experience, building upon my intervention as a patient expert on a National Academies of Sciences, Engineering, and Medicine (NASEM) panel for defining Long COVID, which examined the USG. In the second part, I raise some pressing concerns to address when approaching Long COVID as a disease entity and as a concept, which I originally submitted to NASEM. In the third part, I offer a critical appraisal of the NASEM definition, the most recent benchmark for Long COVID in the US. The review highlights the importance of broad, expansive and inclusive definitions for Long COVID, accounting for the disease’s heterogeneous, fluctuating and multi-system manifestations. Clinical case definitions for Long COVID must retain their focus on the broader spectrum and scope of the disease entity, while incorporating feedback from people with lived experience, advocates and patient-researchers. Full article

This study investigates the impact of the COVID-19 pandemic on clinically diagnosed depression in South Korea, focusing on gender disparities and structural risk factors such as job loss and childcare burden. Although mental health inequalities have received growing attention during the pandemic, most existing research relies on self-reported survey data with inherent limitations. To address this gap, we utilized administrative health data from a 2% stratified random sample of the total population (N = 297,368) in the National Health Insurance Database, focusing on employed individuals without a prior history of depression. Multivariable Cox proportional hazard regression revealed that women had higher risks of depression than men, particularly among those in their 20s to 40s, those who experienced job loss, those who had children aged 7–9, and those who belonged to high-income groups. These findings suggest that the intersection of employment instability and caregiving responsibilities disproportionately affected women’s mental health during the pandemic. The results underscore the urgent need for gender-sensitive public health policies that expand childcare support, institutionalize flexible work arrangements such as telecommuting, and enhance access to targeted mental health services to reduce pandemic-induced gender disparities in mental health. Full article

Since December 2019, the COVID-19 pandemic caused by SARS-CoV-2 has reached approximately 769 million people, leading to more than 7 million deaths worldwide. Faced with the possibility of other respiratory pathogens co-infecting patients and modifying their clinical response to SARS-CoV-2, some researchers have explored this line of investigation. The relationship between these co-infections remains unclear, underscoring the need to deepen our understanding of interactions among pathogens and between pathogens and the host. Thus, the present study employed RT-qPCR to assess the presence of Human Adenovirus (HAdV), Influenza A (Flu A), Influenza B (Flu B), Human Metapneumovirus (HMPV), Respiratory Syncytial Virus (RSV), Human Rhinovirus (HRV), and Parainfluenza Virus (PIV). Nasopharyngeal samples (187) from adult patients exhibiting respiratory symptoms were collected between February 2021 and November 2022 at the University Hospital Polydoro Ernani de São Thiago in Florianópolis, SC, Brazil. The present findings revealed that 25.16% of samples tested positive for non-SARS-CoV-2 respiratory viruses (29.8%—HRV; 5.3%—PIV; 4.3%—RSV; and 1.1%—HMPV). In the 74.84% of SARS-CoV-2-positive patients, co-infection was observed in 9.7% of patients, with 7.5% being HRV, 1.1% HAdV, and 1.1% Influenza A. Since co-infections can potentially alter patient prognoses and impact local epidemiological dynamics, this study highlights the significance of ongoing monitoring and epidemiological assessment through genomic surveillance of other clinically relevant respiratory pathogens. Full article

Background: Vaccination is a crucial public health measure to control infectious diseases, including seasonal influenza. Yet, vaccine uptake varies globally due to sociodemographic factors, misinformation, and access disparities. Objectives: The objective of this study was to assess the prevalence and sociodemographic factors associated with vaccination and the main reasons for vaccine hesitancy in Albania. Methods: A cross-sectional study, conducted in Albania in November–December 2021, included a sample of 1302 individuals aged ≥18 years (≈57% females; mean age: 38.3 ± 15.0 years; response rate: ≈87%). A structured questionnaire was administered inquiring about co-vaccination status against seasonal influenza and COVID-19, reasons for not being vaccinated, and sociodemographic characteristics of participants. Binary logistic regression was used to assess the association of co-vaccination status with sociodemographic factors. Results: Overall, about 28% of individuals were co-vaccinated against seasonal influenza and COVID-19 at least with one dose (25% in males vs. 29% in females; 22% among 18–24-year-olds vs. 54% among those aged ≥65 years). Independent positive and significant correlates of being co-vaccinated included older age (OR = 7.0, 95%CI = 3.7–12.9) and a higher educational attainment (OR = 2.3, 95%CI = 1.4–3.6). The main reasons for vaccine hesitancy among non-vaccinated individuals included the belief that vaccines are: harmful (72%), not effective (66%), weaken the immune system (58%), are not safe (56%), and preference to recover naturally (52%). Conclusions: This study evidenced a relatively low co-vaccination rate in Albania with significant sociodemographic disparities, notwithstanding the availability of vaccines and their free-of-charge provision to the overall population. Older age and higher educational attainment were identified as independent positive predictors of co-vaccination uptake, suggesting the need for targeted public health strategies to address vaccine hesitancy, particularly among younger and less-educated population categories. Our findings emphasize the importance of tailored communication campaigns and community-based interventions to improve vaccine coverage and mitigate the impact of infectious diseases in Albania and elsewhere. Full article

In assessing disability within rural communities, it is crucial to explore the intersection of sociodemographic and health factors. This cross-sectional study, conducted between June and December 2022 in 16 rural locations in Yucatan, aimed to analyze how sociodemographic and occupational factors influence the perception of disability in Mayan communities, with a particular focus on the impact of the COVID-19 pandemic. Disability was evaluated disability in a sample of 1049 participants using the World Health Organization Disability Assessment Schedule (WHODAS). Descriptive analyses and non-parametric tests were performed to characterize the sample and WHODAS scores. The participants’ mean age was 39.26 ± 17.87 years, and significant differences in disability perception were observed in relation to a COVID-19 diagnosis. Individuals with a confirmed diagnosis reported higher levels of disability in the domains of cognition and community participation (p < 0.05). Age strongly influenced disability (p < 0.05). Additionally, education was negatively associated with disability, suggesting that individuals with lower educational attainment were more likely to report higher disability (p < 0.05). These findings contribute to the understanding of disability in the rural Mayan context. Full article

This study aimed to evaluate the effects of the COVID-19 pandemic on food service operations in a Brazilian tourist area. It is a longitudinal observational study. Data collection was performed through telephone interviews with owners or managers of 54 food service establishments concerning the pre-pandemic period (T0) and two time points during the pandemic (T1 and T2). Findings revealed a reduction in the number of establishments providing on-site service at T1 compared to T0, followed by an increase at T2. A reduction in operating hours (56.7%) and profits (100%) affected more establishments at T1 than at T2 (26.7% and 76.7%, respectively) (p < 0.05). At T2, with the resumption of in-person activities, there was a significant decrease in the use of sales channels such as telephone (p < 0.001), messaging applications (p = 0.0012), and websites/apps/social media (p = 0.009) compared to T0 and T1. The pandemic also caused an increase in mask use by employees (p < 0.01) and the availability of hand sanitizer dispensers at establishments (p < 0.01) during T1 and T2. At T2, there was also an increase in the supply of disposable cutlery, cups (p = 0.02), and gloves for customers (p = 0.015) compared to the pre-pandemic period. Full article

Background: COVID-19 vaccination has been a key tool in protecting healthcare workers (HCWs), but breakthrough infections have occurred. The durability of vaccine-induced immunity and its impact on HCWs remain critical for public health strategies. Methods: In this small cohort study (n = 32), we assessed antibody levels and breakthrough infection rates in HCWs over 12 months post-vaccination, providing insights for booster strategies and infection control. A cohort of 32 HCWs was screened for SARS-CoV-2 infection using weekly self-administered swabs and blood samples collected at baseline, 6 months, and 12 months. SARS-CoV-2 antibodies (IgG, IgM) targeting spike proteins and nucleocapsids were analyzed using a multi-antigen serology panel. Pooled nucleic acid testing was employed for infection detection. Results: Nine participants showed breakthrough infections, with nucleocapsid antibodies indicating prior infection. Eight of these cases occurred after the third vaccine dose during the Omicron-dominant period. Anti-spike antibody levels declined significantly in participants without prior infection, while those with breakthrough infections exhibited increased levels. The half-life of S1 and S1 receptor-binding domain (RDB) vaccine-induced antibodies was 144 and 166 days, respectively, which aligns with CDC data. These findings provide valuable insights for determining the optimal timing of booster doses. Conclusions: Our findings highlight the waning antibody levels over time and the occurrence of breakthrough infections. Although based on a small sample, these data support the need for ongoing monitoring and timely boosters. Full article

The COVID-19 pandemic exacerbated mental illness, accelerated cognitive decline, and deepened social inequalities. In low and middle-income countries (LMIC) such as Panama, it is unclear as to whether, and to what extent, the pandemic lockdowns affected cognitive, mental, and physical health of older adults. This study investigated changes in cognitive function, mental health, and physical health in a sample of Panamanian older adults assessed before and during the pandemic, and examined whether sociodemographic variables were associated with cognition and mental health. Participants completed in-person interviews between 2018 and early 2020 and a follow-up telephone interview between February and May 2021. Repeated measures analyses showed no significant changes in cognitive function or depression; however, participants reported fewer chronic illnesses. Linear regression analysis indicated that higher cognitive function during the pandemic was associated with younger age, higher education, and having sufficient income. An attrition analysis compared participants who completed both interviews to those who were lost to follow-up, revealing that participants who dropped out of the study had lower socioeconomic status and greater impairment at baseline. These findings highlight the need for targeted support for vulnerable older adults during public health crises. Full article

The COVID-19 pandemic precipitated unprecedented social isolation measures, profoundly disrupting daily life, educational routines, and mental health worldwide. University students, already susceptible to psychological distress, encountered intensified challenges under remote learning and prolonged confinement. This longitudinal study examined fluctuations in anxiety and mood among 102 Brazilian university students during the pandemic, distinguishing between those solely engaged in academic pursuits and those simultaneously balancing work and study. Data collected via the Brunel Mood Scale and State-Trait Anxiety Inventory in April and July 2021 revealed that students exclusively focused on studies exhibited significant increases in depressive symptoms, anger, confusion, and anxiety, alongside diminished vigor. Conversely, participants who combined work and study reported reduced tension, fatigue, confusion, and overall mood disturbance, coupled with heightened vigor across the same period. Notably, women demonstrated greater vulnerability to anxiety and mood fluctuations, with socioeconomic disparities particularly pronounced among females managing dual roles, who reported lower family income. These findings suggest that occupational engagement may serve as a protective factor against psychological distress during crises, underscoring the urgent need for tailored mental health interventions and institutional support to mitigate the enduring impacts of pandemic-related adversities on the student population. Full article

The P1104A variant in the TYK2 gene is recognized as the first common monogenic cause of tuberculosis, and recent studies also suggest a potential role in COVID-19 severity. However, its frequency and impact in admixed Latin American populations remain underexplored. Therefore, we investigated the P1104A/TYK2 variant in a cohort comprising 1826 RT-PCR-confirmed COVID-19 patients from Southern Brazil. Cases were stratified by severity into non-severe (n = 1190) and severe (n = 636). Three homozygous individuals were identified—one non-severe and two severe cases—although no statistically significant association with disease severity was observed. The frequency of the C allele in the COVID-19 cohort (2.85%) was significantly higher than in Brazilian population databases, including “DNA do Brasil” (1.81%, p < 0.001) and ABraOM (2.34%, p = 0.03), but lower than in the multi-ancestry gnomAD database (3.71%, p = 0.01), possibly reflecting ancestry bias. We also observed associations between COVID-19 severity and sex (p = 0.003), age (p < 0.001), obesity (p < 0.001), diabetes (p < 0.001), and hypertension (p < 0.001). Future studies in larger and more diverse cohorts are needed to characterize the prevalence of the variant in admixed populations and assess its contribution to COVID-19 susceptibility. Full article

Background: The surge in COVID-19 cases during the pandemic created a disease burden. An epidemiological study on COVID-19 is required as not much is known about the impact of containment and mitigation on health. We aimed to compare the epidemiological features during the years of the COVID-19 pandemic in the Vidarbha region in Maharashtra, India, to understand the epidemiology changes throughout the pandemic’s progression. Method: All of the cases reported at our testing centers in Nagpur and its periphery during the three years of the pandemic (i.e., from February 2020 to December 2022) were included. Descriptive analyses of variables of interest and statistical measures were compared. Results: There were 537,320 tests recorded during the study period. Of these, 13,035 (13.29%), 42,909 (13.70%), and 19,936 (15.91%) tested positive in 2020, 2021, and 2022, respectively. Hospitalization decreased from 2020 to 2022. An age group shift from 45 to 16–30 years over the pandemic was noticed. Seasonally, positivity peaked in September (27.04%) in 2020, in April (43.4%) in 2021, and in January in 2022 (35.30%). The estimated case fatality ratio was highest in 2021 (36.68%) over the three years in the hospital setting. Conclusion: Understanding the changing epidemiology of SARS-CoV-2 strengthens our perceptive of this disease, which will aid in improving the healthcare system in terms of both controlling and preventing the spread of COVID-19. Full article

Objectives: This study investigated levels of work engagement and the occurrence of compassion fatigue among nursing professionals during the COVID-19 pandemic. Methods: A cross-sectional, descriptive, and correlational study was conducted at a Brazilian university hospital between February and April 2022. The Brazilian versions of the Utrecht Work Engagement Scale (UWES-9) and the Professional Quality of Life Scale (ProQOL-BR) were administered. Results: High levels of compassion satisfaction (44.9 points), low levels of burnout (21.0 points), and low levels of secondary traumatic stress (22.8 points) were observed. No professional demonstrated a profile consistent with compassion fatigue. Engagement levels were high for dedication (5.3) and moderate for vigor (4.9), absorption (4.5), and overall engagement (4.9). Burnout showed moderate negative correlations with vigor (r = −0.611, p = 0.005) and dedication (r = −0.599, p = 0.019). Compassion satisfaction showed moderate positive correlations with vigor (r = 0.522, p < 0.001) and dedication (r = 0.572, p < 0.001). The overall engagement score was moderately and positively correlated with compassion satisfaction (r = 0.532, p < 0.001). Conclusions: This study identified high levels of work engagement, especially regarding dedication, and low levels of compassion fatigue among nursing professionals. The data suggest that even amid the emotional and physical demands imposed by the pandemic, participants preserved their emotional well-being and maintained a positive relationship with their work. Full article

Breast milk can provide passive immunity to infants, serving as a valuable source of maternal antibodies while remaining a non-invasive sample for investigating maternal immune responses. To date, no studies have evaluated SARS-CoV-2 and potentially cross-reactive HCoV antibodies in breast milk following bamlanivimab administration. A 36-year-old postpartum female was PCR-positive for SARS-CoV-2 four days post-delivery. Bamlanivimab was administered intravenously two days later. Breast milk was collected before bamlanivimab infusion, daily for two weeks post-infusion, then weekly until 102 days post-infusion. Mother and infant sera were collected only at 102 days post-infusion. All milk and serum samples were tested for IgG antibodies against SARS-CoV-2 and HCoV. We observed two distinct SARS-CoV-2 antibody peaks at days 3 and 29 post-infusion, likely representing bamlanivimab transfer and the post-infection antibody response. Beta-HCoV antibodies showed two peaks at days 6 and 29, potentially representing backboosted beta-HCoV responses and/or antibody cross-reactivity with SARS-CoV-2. Infant seropositivity for SARS-CoV-2 102 days post-infusion may represent antibodies from passive transfer via breastfeeding or a subclinical infection. This case highlights the value of breast milk as a non-invasive and repeatable sample to help understand maternal immune responses post-infection, exogenous antibody infusion, and passive antibody transfer during breastfeeding, which can provide insights into maternal–infant health research. Full article

COVID-19 vaccine hesitancy (VH), like attitudes towards other vaccines, is a critical global public health concern. Despite numerous studies covering psychological, sociodemographic, and other determinants of vaccine acceptance, resistance, and hesitance, few studies have reported these factors among students, particularly in politically unstable settings like Ukraine. This cross-sectional, descriptive, and quantitative study assesses hesitancy towards COVID-19 vaccines, utilizing the 5Cs Model. Among 936 respondents surveyed in 2023, 64% received at least one shot of the COVID-19 vaccine (acceptant), 11% were still considering getting vaccinated (hesitant), and 25% refused vaccination (resistant). Vaccination behavior is significantly associated with the 5Cs. Higher collective responsibility significantly increased acceptance and reduced resistance, while higher constraints lowered the chances of being either acceptant or resistant. Confidence protected against resistance. Complacency, counterintuitively, reduced odds of resistance, pointing to differences between passive hesitancy and active refusal. Male gender and sources of information and misinformation influenced confidence. Collective responsibility was positively associated with official sources and negatively with conspiracy beliefs. Complacency increased with official sources, while constraints and calculation were least explained by predictors. Practical barriers should be tackled through improved accessibility and fostering collective responsibility via targeted communication strategies. These findings provide actionable insights for policymakers, healthcare providers, and academic institutions to enhance vaccine uptake among university students, particularly in crisis settings. Full article

The COVID-19 pandemic, caused by SARS-CoV-2, has led to a wide range of acute and chronic disease manifestations. While most infections are mild, a significant number of patients develop severe illness marked by respiratory failure, thromboinflammation, and multi-organ dysfunction. In addition, post-acute sequelae—commonly known as long-COVID—can persist for months. Recent studies have identified the emergence of diverse autoantibodies in COVID-19, including those targeting nuclear antigens, phospholipids, type I interferons, cytokines, endothelial components, and G-protein-coupled receptors. These autoantibodies are more frequently detected in patients with moderate to severe disease and have been implicated in immune dysregulation, vascular injury, and persistent symptoms. This review examines the underlying immunological mechanisms driving autoantibody production during SARS-CoV-2 infection—including molecular mimicry, epitope spreading, and bystander activation—and discusses their functional roles in acute and post-acute disease. We further explore the relevance of autoantibodies in maternal–fetal immunity and comorbid conditions such as autoimmunity and cancer, and we summarize current and emerging therapeutic strategies. A comprehensive understanding of SARS-CoV-2-induced autoantibodies may improve risk stratification, inform clinical management, and guide the development of targeted immunomodulatory therapies. Full article

Background: This study aimed to assess the prevalence of SARS-CoV-2 infection, vaccination, and immune status among a population, both Dentists and University Professors, within a clinical setting at one and at 12 months after COVID-19 vaccination. Methods: A cross-sectional study involving 47 professionals (aged 27–52) was conducted in the University Fernando Pessoa. Participants completed an online survey on SARS-CoV-2 infection status and vaccination, received and provided plasma samples for serological analysis. The protocol was approved by the UFP-Ethics Committee. Anti-S1-RBD SARS-CoV-2 IgM and IgG antibody titration values (AU/mL) were measured, by enzyme-linked-immunosorbent assay (ELISA), with reactive immunoglobulins (Ig) seropositivity for values ≥1 AU/mL. Results: SARS-CoV-2 infection rate increased from 8.5% in July 2021 to 48.9% in June 2022, with 8.5% experiencing reinfection. Vaccination rate was 91.5% by July 2021 and increased slightly to 93.6% by June 2022; 72.3% of the sample received a third dose. IgG seropositivity increased from 91.5% to 95.7% in June 2022. After one-year, significant associations were found between IgG seropositivity and both participant’s age (p = 0.009; <50 years) and vaccine doses (p = 0.003; 1–3 doses) received. Conclusions: SARS-CoV-2 infection rate, vaccination, and IgG seropositivity rates were high and increased over one year. The age and vaccination status were associated with the immunity status at 12th month follow-up. Findings highlight variability in IgG seroprevalence due to multiple influencing factors, which justifies future studies. Full article

People living with HIV (PLWH) faced diverse challenges during the COVID-19 pandemic, including disruptions to care, housing instability, emotional distress, and economic hardship. This study used graph-based clustering methods to analyze pandemic-era experiences of PLWH in a national sample from the NIH’s All of Us dataset (n = 242). Across three graph configurations we identified consistent subgroups shaped by social connectedness, housing stability, emotional well-being, and engagement with preventive behaviors. Comparison with an earlier local study of PLWH in Illinois confirmed recurring patterns of vulnerability and resilience while also revealing additional national-level subgroups not observed in the smaller sample. Subgroups with strong social or institutional ties were associated with greater emotional stability and proactive engagement with COVID-19 preventive behaviors, while those facing isolation and structural hardship exhibited elevated distress and limited engagement with COVID-19 preventive measures. These findings underscore the importance of precision public health strategies that reflect the heterogeneity of PLWH and suggest that strengthening social support networks, promoting housing stability, and leveraging institutional connections may enhance pandemic preparedness and HIV care in future public health crises. Full article

Background/Objectives: Vaccine hesitancy is becoming an increasing concern, leading to preventable outbreaks of infectious diseases. During the COVID-19 pandemic, the United States served as an intriguing case study for exploring how risk perception and trust in health authorities, including scientists, are influenced by government policies and how these factors affect vaccine hesitancy. Methods: We conducted a secondary analysis using the MIT COVID-19 Survey dataset to investigate whether risk perception and trust differ between states governed by Democratic or Republican governors. Results: Our analysis (n = 6119) found that participants did not vary significantly by state political affiliation in terms of their sociodemographic factors (such as age, gender, self-rated health, education, and whether they live in a city, town, or rural area), their perceived risk for the community, or their ability to control whether they become infected. However, there was a difference in the perceived risk of infection, which was higher in states governed by Republicans. Trust also varied by gubernatorial affiliation, with higher levels of trust reported among residents of Democratic-leaning states. We also found a strong mediation effect of trust on vaccine hesitancy, but this was not the case for risk perception. Conclusion: Therefore, it appears that vaccine acceptance relies on trust in health authorities, which is influenced by governmental policies. State officials should work with local health officials to build trust and increase timely responses to public health crises. Full article

The COVID-19 pandemic fundamentally disrupted assumptions about entrepreneurship, career planning, and professional development. This study explored how the pandemic influenced the entrepreneurial intentions of undergraduate business students in the United States. Using a qualitative methodology based on in-depth interviews with 31 students at a public Midwestern university, the research interpreted student narratives through the lenses of effectuation theory, resilience theory, and the theory of planned behavior. Findings revealed that many participants reframed entrepreneurship as a strategy for navigating economic uncertainty and enhancing personal agency. Students reported valuing adaptability, resourcefulness, and opportunity recognition, often experimenting with side hustles during the pandemic as a means of resilience. Their entrepreneurial thinking shifted from purely economic motivations toward aspirations for flexibility, self-fulfillment, and purposeful work. The study highlights the formative role of crisis contexts in shaping entrepreneurial identity among emerging professionals. It suggests that entrepreneurship education should move beyond traditional models, fostering skills for navigating complexity and building resilience. In doing so, the findings contribute to broader conversations about youth entrepreneurship, post-pandemic career development, and the evolving demands of the labor market in times of disruption. Full article

This study included 221 patients with COVID-19 who were admitted to the emergency department of Avicenne Hospital in Rabat between August 2020 and August 2021. Patients were divided into three groups according to their D-dimer levels (<1, 1–2, and >2 µg/mL). Adjusted and unadjusted logistic regression analyses were performed to assess the association between elevated D-dimer levels and in-hospital mortality. Pearson’s correlation analysis was performed to explore the relationship between D-dimer levels and various biological and clinical parameters. The results revealed a statistically significant difference in the mean (SD) age among the three groups (p = 0.006). Analysis showed a statistically significant difference in the means (SD) of oxygen saturation, duration of hospital stay, and breathing rate among the three independent groups of COVID-19 patients. Patients with elevated D-dimer levels (greater than 2 µg/mL) experienced worse outcomes than those in the other groups, with severity, transfer to intensive care, and in-hospital mortality of 55 (40.7%), 35 (16%), and 24 (11%) patients, respectively, with p-values of 0.048, 0.002, and 0.002, respectively. Patients in the D-dimer > 2 µg/mL group had significantly higher C-reactive protein (CRP), lactate dehydrogenase, urea, cardiac troponin, B-type natriuretic peptide, and ferritin levels than those in the other two groups. The p-value was significant among the three groups (p = 0.044, p = 0.001, and p < 0.001). Age and elevated D-dimer levels (greater than 2 µg/mL) were associated with mortality in patients diagnosed with COVID-19. Correlation analysis indicated that D-dimer in COVID-19 patients is associated with worsening respiratory, hepatic, cardiac, and coagulation parameters, suggesting their utility as an integrative marker of disease severity. D-dimer levels > 2 µg/mL were identified as an independent risk factor for COVID-19 in-hospital mortality. Measuring and monitoring D-dimer levels can assist clinicians in taking timely actions and predicting the prognosis of patients with COVID-19. Full article

Background: This study examined risk factors for syndrome novel coronavirus 2 virus (SARS-CoV-2) infection and self-reported adherence to infection prevention and control (IPC) measures among healthcare workers (HCWs) at a hospital in Thailand near the Myanmar border. Methods: From March to July 2022, HCWs aged ≥ 18 with COVID-19 exposure at Mae Sot General Hospital completed a questionnaire on IPC adherence, training, and COVID-19 knowledge. Nasopharyngeal samples were collected bi-weekly for SARS-CoV-2 testing. A mobile application was used for real-time monitoring of daily symptoms and exposure risks. Chi-square, Fisher’s exact tests, and log-binomial regression were performed to investigate association. Results: Out of 289 (96.3%) participants, 27 (9.9%) tested positive for SARS-CoV-2, with cough reported by 85.2% of cases. Nurse assistants (NAs) had a higher risk of infection (adjusted relative risk [aRR] 3.87; 95% CI: 0.96–15.6). Working in inpatient departments (aRR 2.37; 95% CI: 1.09–5.15) and COVID-19 wards (aRR 5.97; 95% CI: 1.32–26.9) was also associated with increased risk. While 81.7% reported consistent hand hygiene, 37% indicated inadequate IPC knowledge. Conclusions: HCWs, especially NAs and those in high-risk departments, should receive enhanced IPC training. Real-time digital monitoring tools can enhance data collection and HCW safety and are likely to be useful tools for supporting surveillance and data collection efforts. Full article

Previous studies about the COVID-19 pandemic on STEMI patient outcomes have conflicting results. It remains unclear if this may be attributed to regional differences and/or differences during COVID-19 wave periods. Using the American Heart Association Get With The Guidelines–Coronary Artery Disease registry data, we evaluated (1) time metrics related to STEMI system goals and (2) regional variation in STEMI incidence and in-hospital mortality during pandemic wave time periods. The study included all patients 18–100 years old admitted with STEMI (n = 72,516) to 1 of 435 American Heart Association Get With The Guidelines–Coronary Artery Disease hospitals (1 October 2019–31 December 2021). Of these, 70.8% were male and 73.0% non-Hispanic White, with a median age of 63 (IQR 18) years. Compared to pre-pandemic time frames, patients with STEMI had a higher risk profile, delayed time to treatment, were treated with fibrinolytic therapy or primary PCI, and were transferred for primary PCI at similar rates, and had higher adjusted in-hospital mortality (during the second wave in the South and Midwest). Preservation of STEMI systems of care resulted in an overall lower in-hospital mortality rate than predicted, although opportunities exist to improve treatment delays. Regional differences in mortality rates require further study. Full article

COVID-19 vaccine hesitancy in Pakistan is a barrier to optimal vaccine uptake and has been situated within a context of hesitancy towards other vaccines. A mixed-methods study was conducted during the initial COVID-19 vaccine roll-out in 2021 in four union councils in Peshawar, consisting of a cross-sectional survey, eight focus group discussions (FGDs) with community members and eight in-depth interviews with healthcare workers (HCWs) to assess perceptions toward vaccines. Multivariable logistic regression was used to assess factors associated with COVID-19 vaccine hesitancy. Of 400 survey participants, 57.3% were vaccine acceptant and 42.8% vaccine hesitant. Just over half (56.8%) perceived COVID-19 vaccines to be safe. Most (88%) reported trust in HCWs to provide accurate vaccine information. FGDs revealed that women received less information about the vaccine compared to men and cultural restrictions were barriers even for those willing to be vaccinated. Correlates of vaccine acceptance included male sex (aOR 2.25; 95% CI 1.29–3.91), age 50 years or greater (aOR 1.74; 95% CI 1.19–6.31), social network support (e.g., vaccine acceptance among an individual’s social network) in receiving COVID-19 vaccines (aOR 2.38; 95% CI 1.45–3.89), community concern about COVID-19 spread (aOR 2.84; 95% CI 1.73–4.66), and trust in HCWs to provide vaccine information (aOR 3.47; 95% CI 1.62–7.42). Future vaccine promotion should prioritize engaging community leaders, sharing transparent information, combatting misinformation and rumors, and implementing household-based interventions especially targeting the importance of vaccination among women and young people to increase uptake. Full article

Soluble CD40 ligand (sCD40L) is a molecule known for its thromboinflammatory properties and may act as a biomarker for platelet activation. Platelets are the principal producers of sCD40L, which is recognized for its impact on platelet function. However, its contribution to the platelet hyperreactivity observed in SARS-CoV-2 infection remains poorly understood. During viral infection, platelets function as crucial intermediaries, engaging with both viruses and leukocytes; and serve as a substantial source of inflammatory mediators, promoting thromboinflammation and immunothrombosis. While platelet hyperactivation is associated with the severity and mortality of COVID-19, the precise function of sCD40L in this setting remains inadequately defined. This study examined the role of platelet-derived sCD40L in platelet activation, aggregation, and thrombosis associated with COVID-19. Platelets from blood samples of 160 patients—102 with non-severe cases and 58 with severe cases—demonstrated heightened activation and aggregation, as well as elevated sCD40L release. In a mouse thrombosis model, sCD40L intensified thrombus development. These findings underscore the essential function of platelet-derived sCD40L in the pathophysiology of COVID-19 and endorse the therapeutic potential of targeting CD40L-mediated pathways to mitigate thromboinflammatory consequences. Full article