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Phase IIB, Randomized, Double-Blind, Placebo-Controlled Clinical Trial of Intravenous Defibrotide for the Prevention and Treatment of Respiratory Distress and Cytokine Release Syndrome in COVID-19.

INTRODUCTION: Endothelial dysfunction is key in COVID-19 pathogenesis. This randomized, double-blind phase IIb trial investigated continuous intravenous infusion of defibrotide in patients hospitalized with SARS-CoV-2 infection and respiratory failure. METHODS: One-hundred and fifty patients were randomized (2:1) to defibrotide or placebo, stratified by disease severity (WHO COVID-19 severity scale 4/5 vs. 6). The primary endpoint was clinical improvement time (days from first improvement through Day 30). RESULTS: Median clinical improvement time was not significantly different with defibrotide versus placebo (15.0 [IQR: 0-24] vs. 20.0 [IQR: 9-25] days; p = 0.10). Day-30 (23.0% vs. 22.0%) and Day-60 (26.0% vs. 22.0%) mortality, reduction in mean fraction of inspired oxygen during treatment, and median duration of hospitalization did not differ with defibrotide versus placebo. Defibrotide demonstrated favorable safety, with no differences versus placebo in serious adverse events (34.0% vs. 36.0%), hypotension (16.0% vs. 12.0%), or hemorrhage (13.0% vs. 8.0%). Exploratory pre-specified biomarker analyses showed greater early d-dimer reduction and lymphocyte recovery with defibrotide, although these results require validation. CONCLUSION: Continuous intravenous infusion of defibrotide was safe but did not improve clinical outcomes in severe COVID-19. Further analyses will explore mechanistic actions and pharmacokinetics of defibrotide and the pathophysiology of endothelial dysfunction in COVID-19. TRIAL REGISTRATION: EudraCT identifier: 2020-001409-21. CLINICALTRIALS: gov identifier: NCT04348383.

Adult

Safety and immunogenicity of an mRNA COVID-19 vaccine administered to adults: A phase 2, randomized, active-controlled trial.

We conducted a phase 2, randomized, active-controlled, observer-blind study (NCT05960097) among healthy adults ≥18 y of age who completed a primary COVID-19 mRNA vaccination series, with or without a booster, ≥3 months earlier. Participants were randomized (1:1:1:1:1) to either receive an investigational bivalent mRNA COVID-19 vaccine encoding ancestral D614G and Omicron BA.4-5 spike proteins (CV0701 mRNA vaccine) at one of three dose levels, an investigational monovalent mRNA COVID-19 vaccine encoding the Omicron BA.4-5 spike protein (CV0601 mRNA vaccine), or a licensed Original Wuhan/Omicron BA.4-5 bivalent mRNA COVID-19 vaccine. The primary objectives were to evaluate reactogenicity, safety and immunogenicity post-vaccination. Secondary and tertiary objectives were to further evaluate humoral and cell-mediated immunity post-vaccination. In total, 425 participants were vaccinated and 381 were included in the Day 29 per-protocol immunogenicity analysis. Most solicited events were mild to moderate. No vaccine-related serious adverse events or myocarditis/pericarditis cases were reported. For the CV0701 mRNA vaccine, a dose-dependent increase in Day 29 neutralizing titers against ancestral D614G and Omicron BA.4-5 was observed. Neutralizing titers against ancestral D614G and Omicron BA.4-5 declined by Days 91 and 181, but remained above baseline. Similar immune responses were observed for the CV0601 mRNA vaccine. At Day 8, CD4+ T cells (Th1 profile) increased in all study groups and CD8+ T cells increased in all study groups, except the lowest CV0701 dose group. The CV0701 and CV0601 mRNA vaccines elicited robust humoral and cellular immunity with an acceptable safety profile, comparable to a licensed, bivalent mRNA vaccine. Clinical Trial Registration EU CT number: 2023-504596-25-00 ClinicalTrials.gov: NCT05960097.

Humans

Cognitive-behavioral therapy for post COVID-19 condition: A pilot randomized controlled trial.

BACKGROUND: The post COVID-19 condition (PCC) is a disabling condition with urgent need for effective treatments. This pilot randomized controlled trial examined the feasibility and efficacy of a cognitive-behavioral therapy (CBT) for PCC in a parallel-group design. METHODS: N = 53 individuals with PCC were randomized to CBT (n = 27) or 16-week wait-list control (WLC) condition (n = 26). One participant allocated to WLC was excluded after randomization, resulting in an intention-to-treat (ITT) sample of N = 52 participants (CBT: n = 27, age: M = 48.59, SD = 11.52, 77.8% female; WLC: n = 25, Age: M = 48.44, SD = 9.81, 60% female). CBT comprised eight group and five individual sessions addressing cognitive and behavioral factors of symptom maintenance (treatment duration if completed: M = 14 weeks, SD = 1 week). Primary outcomes included fatigue (FSS), overall somatic symptom burden (PHQ-15), and respiratory and cardiovascular symptoms (SBQ™-LC "Breathing" and "Circulation"), assessed at pre-, post-assessment, and follow-up. RESULTS: Participants receiving CBT showed a significant medium-sized reduction in fatigue directly after treatment compared to the WLC condition (d = -0.58, p = .045), whereas the WLC group showed a significant increase in overall somatic symptoms (d = 0.60, p = .027). Results for respiratory symptoms were mixed, showing inconsistent patterns across analyses. Retrospectively assessed feasibility and treatment satisfaction were good, with few adverse effects reported. CONCLUSIONS: This pilot trial suggests the feasibility and preliminary efficacy of CBT for PCC. Larger RCTs with active control groups should confirm these findings.

Humans

2024-2025 BNT162b2 KP.2 COVID-19 full season vaccine effectiveness from vaccine registries linked to administrative claims in two states: A cohort study in non-immunocompromised adults.

BACKGROUND: Data on effectiveness of COVID-19 vaccinations during the 2024-2025 respiratory season are limited, particularly among those with underlying medical conditions (UMC). We estimated BNT162b2 KP.2 vaccine effectiveness (VE) against COVID-19-associated hospital admission, emergency department (ED), and urgent care (UC) visits in two U.S. states. METHODS: Retrospective cohort study of non-immunocompromised adults living in Louisiana or California, with ≥1 year prior continuous enrollment in insurance plans contributing to the HealthVerity claims database beginning August 22, 2024. The effectiveness of BNT162b2 KP.2 vaccine (2024-2025 formulation, hereafter referred to as BNT162b2), measured as a time-varying exposure against hospital admission, ED, or UC encounters with International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code U07.1 was calculated as 1 - adjusted hazard ratio using Cox proportional hazard models adjusted for age group, sex, state, insurance payor, presence or absence of UMCs, and pre-index healthcare utilization. Stratifications included those aged 65 years and older, those aged 18-64 years with UMCs, and those aged 18-64 years without UMCs. RESULTS: The cohort included 6,256,421 individuals (93% California, 7% Louisiana); 330,565 (5%) received the BNT162b2 vaccine. Vaccinated individuals were older and had more comorbidities, wellness visits, and prior influenza vaccination. Overall, 66% of the study population had ≥1 UMC; the most prevalent conditions were obesity (25%), history of immunocompromised conditions (23%), and mental health conditions (19%). COVID-19-related encounter rates for ED, UC or hospitalization were lower among vaccinated compared to unvaccinated persons (25.1 vs 36.3 per 100,000 person-months). Among all adults, VE was 37% against hospitalization, 12% against ED/UC encounters, and 16% against ED/UC/hospitalization encounters. Results were similar across age groups and UMCs. CONCLUSIONS: BNT162b2 provided protection against COVID-19-associated outcomes of ED, UC or hospitalization among non-immunocompromised U.S. adults, including those with UMCs, over the course of the 2024-2025 respiratory virus season, supporting continued vaccine recommendations. REGISTRATION: This study was posted on clinicaltrials.gov prior to analyses (NCT06923137).

Adolescent

Psychological interventions to improve maternal mental health and resilience during pregnancy in the COVID-19 pandemic: a systematic review.

BACKGROUND: During the COVID-19 pandemic, pregnant women experienced increased psychological distress, while access to routine mental health care was often disrupted. Psychological interventions may provide an effective strategy to support maternal mental health under these circumstances. OBJECTIVE: This systematic review aimed to provide an overview of psychological interventions for pregnant women during the COVID-19 pandemic and to evaluate their effectiveness in reducing distress and enhancing resilience. METHODS: A systematic search of four databases was conducted up to 3 September 2025. Randomised and non-randomised studies evaluating psychological interventions during pregnancy were included. RESULTS: Sixteen studies met the inclusion criteria. Interventions included cognitive behavioural therapy, mindfulness-based interventions, psychoeducation, and other psychological approaches delivered through individual, group, digital, or hybrid formats. Most studies reported reductions in depression, anxiety, or stress, and some found improvements in resilience-related factors. However, the methodological quality was modest; with heterogeneous outcome measures and limited follow-up. CONCLUSIONS: Overall, psychological interventions adapted for digital or hybrid delivery show promise for improving maternal emotional well-being in times of crises. The findings suggest that accessible and scalable psychological interventions may support maternal mental health during crisis situations when routine care is disrupted. Future research should prioritize larger, methodologically rigorous trials with standardized outcomes, and longer follow-up periods.

Humans

Plasma proteomics reveal SERPINA1 and CD59 as candidate biomarkers for COVID-19 severity stratification and prognosis prediction.

BACKGROUND: COVID-19 has been closely associated with coagulation abnormalities. However, existing biomarkers, including D-dimer and fibrin degradation products (FDP), exhibit limited accuracy in stratifying disease severity and predicting long-term clinical outcomes. OBJECTIVES: This study aimed to use proteomic analysis to identify plasma biomarkers associated with COVID-19 severity and prognosis, and validate their predictive utility for mortality and thromboembolic complications. METHODS: Plasma proteomic profiles were analyzed across three COVID-19 severity classes. Differential expression analysis and functional analysis were performed. Clustering analysis was used to identify proteins correlated with disease severity. Candidate biomarkers were validated in an independent cohort. Predictive performance of the biomarkers for mortality, sepsis and venous thromboembolism was evaluated using bootstrap-corrected ROC analyses and multivariable regression analyses. RESULTS: Proteomic analysis revealed progressive involvement of the coagulation and complement pathway with increasing disease severity. SERPINA1 and CD59 were identified as candidate biomarkers and exhibited significantly higher plasma levels in severe cases. Bootstrap-corrected ROC analyses demonstrated strong predictive performance: SERPINA1 achieved AUCs of 0.775 and 0.924 for 30-day and 12-month mortality, and CD59 achieved AUCs of 0.720 for sepsis; the combined model further improved prediction of 12-month mortality (AUC 0.946) and sepsis (AUC 0.904), outperforming D-dimer and FDP. Multivariable regression confirmed their independent prognostic value. CONCLUSION: This exploratory study identifies SERPINA1 and CD59 as candidate prognostic biomarkers in COVID-19, highlighting the role of coagulation and complement-related pathways in disease severity and warranting further prospective validation.

Humans

Implementation of a Face-To-Face Vs Virtual Peer-Integrated Collaborative Care Intervention for Mental Health Treatment of Physical Trauma Survivors: A Qualitative Study of Lessons from the COVID-19 Pandemic.

OBJECTIVE: We assessed the impact of the COVID-19 pandemic on the implementation of a peer-integrated enhancement of integrated clinical care intervention to address the mental health needs of 450 patients undergoing treatment for a physical injury. METHODS: Qualitative data were collected by 7 clinician investigators of a randomized controlled trial acting as participant observers in a trauma care setting of a major U.S. metropolitan hospital and analyzed in collaboration with an external mixed methods specialist. RESULTS: The pandemic created or exacerbated several implementation barriers, including increased risk of infection, homelessness, hospitalizations and comorbid conditions such as fentanyl overdoses that increased demand on emergency department and Trauma Center services, imposition of safety measures to reduce risk of infection in clinical settings, transition from face-to-face to virtual interactions with study patients, shortages of specialty mental health providers, suspension of recruitment of patients into the study, scheduling calls with patients, and an increased workload for the study clinical interventionists. Peer specialists perceived the transition to virtual interactions with patients reduced their effectiveness; however, this was not reflected in assessments of patient satisfaction with services received and may have inadvertently increased adoption by Trauma Center staff. Reduction in reach of the intervention to target population was temporary. CONCLUSIONS: The COVID-19 pandemic exacerbated existing barriers and created new barriers to successfully implementing evidence-based practices in trauma care settings, resulting in an attenuation of their effectiveness. However, the shift from face-to-face to virtual services delivery may have actually led to improved implementation outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03569878. Registered June 15, 2018.

Humans

The impact of the COVID-19 pandemic on osteoporotic fractures: a systematic review and meta-analysis.

BACKGROUND: Recent reports suggest that the COVID-19 pandemic and associated lockdowns may have influenced the epidemiology of osteoporotic fractures, but results vary across regions and fracture types. The aim of this study was to provide evidence-based insights into the impact of the pandemic on osteoporotic fracture incidence. METHODS: We searched four databases (PubMed, Embase, Cochrane Library, and Web of Science) up to August 2025 for observational or retrospective studies comparing osteoporotic fracture incidence during the COVID-19 pandemic (2020) with the pre-pandemic period (2019). The primary outcome of interest was the change in fracture incidence, analysed using risk ratios (RR) with 95% confidence intervals (CI) in Review Manager 5.4. Subgroup analyses were performed by sex, geographic region, and fracture type. RESULTS: Nine studies meeting the inclusion criteria were analysed. Overall, "all types" of osteoporotic fractures showed a significant decrease during the pandemic (RR = 0.85, 95% CI 0.80-0.91, p&#x2009;<&#x2009;0.0001). Specifically, forearm fractures decreased significantly (RR = 0.87, 95% CI 0.79-0.96, p&#x2009;=&#x2009;0.002). However, for the most clinically significant fractures, no statistically significant global change was found for hip fractures (RR = 0.93, 95% CI 0.76-1.15, p&#x2009;=&#x2009;0.14) or vertebral fractures (RR = 1.35, 95% CI 0.85-2.15, p&#x2009;=&#x2009;0.20). In regional subgroup analysis, hip fracture incidence decreased significantly in South America (RR = 0.79, p&#x2009;=&#x2009;0.0004) and in both males and females, but no significant change was observed in Europe (RR = 0.92, 95% CI 0.81-1.04, p&#x2009;=&#x2009;0.17). CONCLUSION: During the COVID-19 pandemic, there was a decrease in the incidence of minor fractures, such as those of the forearm, likely due to reduced outdoor activity. However, the incidence of major osteoporotic fractures (hip and vertebral) remained stable globally, with significant reductions observed only in specific regions like South America.

Humans

Associations Between Routine Vaccinations and the Risk of New-Onset Idiopathic Uveitis.

OBJECTIVE: To evaluate the association between vaccination and the risk of new-onset idiopathic uveitis (NIU). DESIGN: Retrospective cohort study of aggregated electronic health records from multiple health systems across the United States. SUBJECTS: Subjects who received the coronavirus disease 2019 (COVID-19), human papillomavirus (HPV), varicella, recombinant herpes zoster, or live herpes zoster vaccinations from 2006 to 2025 and propensity-score matched controls. INTERVENTION: Vaccines against COVID-19, HPV, varicella, recombinant herpes zoster, or live herpes zoster. MAIN OUTCOMES AND MEASURES: The main outcome was the incidence of NIU at 3, 6, and 12 months following vaccination. Vaccinated patients were compared with matched controls who did not receive the respective vaccines. Analyses were repeated, excluding patients with previous diagnosis of the respective viral infection. Risk ratios (RR) with 95% confidence intervals (CIs) were calculated for overall NIU and constituent subtypes (anterior, intermediate, posterior, and panuveitis). RESULTS: All tested vaccinations were associated with reduced risk of NIU through 12 months compared with matched controls. Relative risk reductions were 65% for COVID-19 (RR, 0.35; CI, 0.33-0.37), 56% for HPV (RR, 0.44; CI, 0.35-0.54), 71% for varicella (RR, 0.29; CI, 0.25-0.33), 68% for live zoster (RR, 0.32; CI, 0.23-0.43), and 69% for recombinant zoster vaccination (RR, 0.31; CI, 0.26-0.37). Similar reductions were observed after excluding patients with prior diagnoses of the respective viral infections. CONCLUSIONS: Vaccination was associated with a lower risk of idiopathic uveitis, representing the complex interplay between immune modulation and the development of NIU.

Humans

Evaluation of one-step amplicon-based targeted enrichment for SARS-CoV-2 whole-genome sequencing using the Midnight amplicon scheme.

Genomic surveillance proved invaluable during the COVID-19 pandemic for tracking SARS-CoV-2 variants and guiding outbreak responses, underscoring the ongoing need to reduce whole-genome sequencing (WGS) costs and improve workflow efficiency to ensure accessibility in resource limited settings. Here, we evaluated a one-step reverse transcription polymerase chain reaction (RT-PCR) approach using the Midnight V2 primer scheme for targeted amplification of the SARS-CoV-2 genome, assessed its compatibility with Illumina sequencing, and compared its performance to a well-established two-step method. Initially, we determined optimal RT-PCR reaction conditions using the Midnight V2 primer panel for the one-step RT-PCR kit and scaled reaction volumes for both RT-PCR and library preparation. Clinical specimens (n&#x202f;=&#x202f;53) that had undergone routine WGS for surveillance purposes using the established two-step RT-PCR method were compared using the one-step RT-PCR assay. For samples with genome completeness greater than 70%, both methods gave comparable results with similar sequence coverage and 100% concordance for lineage assignment. Further investigation revealed a higher percentage of reads aligning to the SARS-CoV-2 genome with a greater depth of coverage using the one-step method compared to the two-step method. Finally, analysis of scaled one-step and library reaction volumes revealed significant cost savings for samples undergoing WGS. Overall, the results presented here verify the accuracy and reproducibility of one-step targeted amplification and offer an efficient and cost-effective workflow for routine SARS-CoV-2 genomic surveillance.

Humans

Financial incentives and social messaging for repeat SARS-CoV-2 antibody testing among the underserved: A randomized trial.

Financial incentives may influence health behavior beyond their expected monetary value, and their effectiveness may depend on how the behavior is framed. Behavioral theories of decision making suggest that individuals may value protection against small-stakes losses more than expected utility predicts, while theories of family-centered health behavior suggest that messages emphasizing benefits to family members may strengthen participation in preventive health activities. We tested these ideas in a 2&#xd7;2 factorial randomized trial involving 625 households recruited from a Federally Qualified Health Center serving low-income Latino/Hispanic communities. Participants completed repeat SARS-CoV-2 antibody testing. The trial crossed two messaging strategies (Family vs. Personal) with two incentive structures (Loss Protection vs. Lottery) that offered equivalent expected monetary value. Family Messaging emphasized protecting one's family from COVID-19, whereas Personal Messaging emphasized protecting oneself. Loss Protection allowed participants to secure an at-risk reward through repeat testing, whereas the Lottery condition offered a chance of a large reward. Repeat testing was approximately 8 percentage points higher under Family Messaging and 7 percentage points higher under Loss Protection. Baseline trust in medical providers, financial barriers to vaccination, and risk aversion were associated with initial testing, whereas household characteristics were not associated with repeat testing. Incentive design may matter beyond expected monetary value and that framing health behaviors in terms of family welfare may increase participation in repeated healthy activities. Broadly, the results support behavioral theories emphasizing loss aversion, anticipated regret, and family-centered motivations, and suggest practical approaches for improving engagement in repeat health behaviors. CLINICALTRIALS.GOV REGISTRATION NUMBER:: NCT01901624.

Adult

Timeliness of publication of randomized controlled trials in rheumatology: A systematic review.

OBJECTIVE: To systematically review the (1) timeliness of publication of randomized controlled trials (RCTs) in rheumatology, (2) impact of the COVID-19 pandemic on time to publication, and (3) factors associated with publication delays. METHODS: We searched Medline, Embase, EBM Reviews, Cochrane Central Register of Controlled Trials, and Scopus from January 1, 2018, to June 30, 2023 for Phase 3, superiority, parallel-design RCTs that evaluated any treatment for a rheumatologic illness or a rheumatologic treatment for COVID-19 and reported clinical primary efficacy outcome. Outcomes of interest were time to publication after trial completion and publication delay of >2 years after trial completion. RESULTS: 448 RCTs were included in this systematic review. Median time from completion to publication was 549 days and 65.9 % RCTs were published within 2 years of completion. Compared with RCTs on rheumatologic diseases, RCTs on COVID-19 were published sooner (253 vs. 549 days; p < 0.001) and were more likely to be published within 2 years (adjusted OR 9.49, 95 % CI 2.07 to 43.61). Compared with RCTs completed before March 1, 2020, RCTs completed after March 1, 2020, were published sooner (327 vs. 724 days; p < 0.001) and were more likely to be published within 2 years (adjusted OR 9.40, 95 % CI 5.14 to 17.21). Time from RCT completion to submission accounted for most (67 %) of the time to publication. CONCLUSIONS: Publication delay continues to be an important concern in dissemination of clinical research. Most of the delays in publication were attributable to delays in submission to journals after trial completion.

Humans

Making waves: toward systems-level interpretation of hormonal and endogenous biomarkers in wastewater-based epidemiology.

Wastewater-based epidemiology (WBE) has proven invaluable for population health monitoring, most notably during the COVID-19 pandemic. Yet current WBE largely relies on exogenous markers such as drugs, pathogens, and their metabolites, limiting surveillance to what communities are exposed to. We argue for expanding WBE towards endogenous biomarkers, particularly hormones, which provide insights into physiological stress, metabolic function, and endocrine activity. Hormone-based WBE offers new opportunities to capture population-level biological responses to societal and environmental stressors, disasters, and chronic disease burdens at the community scale. This perspective outlines a systems-level framework for integrating hormonal signals in wastewater with clinical data, behavioral indicators, environmental factors, and digital markers to support more robust and context-aware public health surveillance. We highlight key technical considerations, interpretive challenges, and opportunities for translational pilot studies. By moving beyond exposure tracking toward more integrated interpretation of biological responses, hormone-informed WBE may contribute to more resilient, inclusive, and actionable public health infrastructure.

Humans

A genome-wide coverage-based pipeline for the identification of host-derived candidate DNA biomarkers from cell-free blood.

We have created a new data-analysis pipeline for the discovery of host-specific candidate DNA biomarkers derived from sequencing data of cell-free blood. Unlike approaches that rely on specific molecular or genetic signatures, our method leverages the coverage distribution of cell-free DNA sequences mapped to a reference genome, applying statistical analyses to identify informative short genomic regions for biomarker discovery. The pipeline is applicable to diverse diseases and can be used to analyze cell-free DNA sequences from plasma or serum to identify candidate biomarkers that are characteristic of disease states in mammals. Core functionalities were developed in Java and integrated with open-source software tools for the preprocessing of raw sequencing data, complemented by Python scripts for the machine-learning analysis and statistical validation. The pipeline is designed for HPC use and users can access the pipeline through a Galaxy workflow, which offers a user-friendly web interface for input selection prior to execution and analysis progress monitoring. Performance tests, carried out using duplicate sets of COVID-19 samples and controls, showed linear scalability of execution time with an increasing dataset size, as well as a substantial reduction in execution time through parallelized computation, whereby each HPC node is used to process the data of one chromosome. Further statistical tests confirmed the quality of the pipeline's results by showing that the set of identified candidate biomarkers remained stable across varying dataset sizes.

Biomarkers

The return of measles: a dangerous comeback.

PURPOSE OF REVIEW: Measles has reemerged as a significant global public health threat, with increasing morbidity and mortality associated with declining vaccination rates. This review summarizes current global outbreaks, history of measles, vaccination and elimination status, vaccine hesitancy, and outbreak response and lessons learned highlighting different novel digital epidemiological tools. RECENT FINDINGS: Measles continues to surge worldwide with an estimated 11 million infections in 2024, which is more than prepandemic levels. Developing and developed countries are both facing measles outbreaks, with the United States at risk of losing measles elimination status. Recent studies have showed that worldwide percentages of two-dose measles vaccination were lower than 95% that is required to interrupt measles transmission in all WHO regions. Novel epidemiological tools such as interactive simulators, real-time use of dynamic models, serosurveillance, and others are transforming measles outbreak response and enable earlier outbreak detection, tracking, and targeted public health interventions. SUMMARY: Vaccine hesitancy is one of the top global health threats and developing a tailored evidence-based approach is necessary to establish and maintain measles elimination.

Humans

Approaches to observational study designs and analytical options to evaluate the safety of multi-dose vaccines: a systematic review.

INTRODUCTION: Observational studies require careful considerations when evaluating the safety of multidose vaccines. We reviewed design and analytical approaches in observational studies evaluating the safety of multidose vaccines in the post-licensure phase. METHODS: EMBASE, MEDLINE, Web of Science, and Scopus (2018-2022) were searched for hypothesis-testing studies evaluating the safety of multidose vaccines. Key features from frequently used designs were extracted. RESULTS: Among 123 eligible studies, cohort (46%) and self-controlled case series (SCCS)/self-controlled risk interval (SCRI) (40%) followed by case-control (12%) were the most common designs, and 15% of studies used multiple designs. Among cohort studies evaluating multiple doses, vaccination date (36%) and cohort entry with time-updated exposure status (32%) were frequent approaches used to define time zero. Twenty-eight percent of cohort studies did not report time zero; all but one evaluated COVID-19 vaccine effect on post-delivery and fertility-related outcomes. For SCCS/SCRI, 64% of studies accounted for event-dependent exposures, mainly by including pre-exposure periods (53%) and modified SCCS model (48%), while 20% employed multiple correction strategies. Among studies using multiple designs, 68% reached consistent conclusions. CONCLUSIONS: SCCS/SCRI and cohort designs dominate multidose vaccine safety studies. Clear reporting on time zero in pregnancy and fertility-related cohort studies, and on addressing event-dependent exposures in SCCS/SCRI studies is needed, along with guidance on interpreting results from multiple designs.

Humans

A pragmatic randomized controlled trial of self-directed online writing interventions for posttraumatic stress symptoms in a real-world digital setting.

Background: Public health and other large-scale crises, such as the COVID-19 pandemic, have intensified the global mental health burden, creating unprecedented demand for accessible interventions for posttraumatic stress symptoms (PTSS).Objective: We evaluated the feasibility and effectiveness of two self-directed online writing interventions embedded within China's WeChat ecosystem during the COVID-19 pandemic through a pragmatic randomised controlled trial.Methods: Between December 2021 and August 2022, 1,526 adults were screened for PTSS via a Tencent Medinfo Mini-Program. Eligible participants (n&#x2009;=&#x2009;211) were randomised to Guided Narrative Technique-Writing (GNT-W, n&#x2009;=&#x2009;100) or Expressive Writing (EW, n&#x2009;=&#x2009;111). Both interventions comprised three self-directed daily writing sessions delivered entirely online without human support. Primary outcome was PTSD symptom severity (PTSD Checklist-Short), assessed at baseline, post-intervention, 2-week, and 1-month follow-ups.Results: While initial engagement followed typical digital health patterns (64.5% overall attrition), participants who initiated treatment showed strong adherence (77% completion). Both interventions were associated with significant within-group reductions in PTSS severity (GNT-W: b&#x2009;=&#x2009;-0.43, p&#x2009;=&#x2009;.023, d&#x2009;=&#x2009;-0.43; EW: b&#x2009;=&#x2009;-0.60, p&#x2009;=&#x2009;.001, d&#x2009;=&#x2009;-0.58), with no significant between-group difference (group &#xd7; time: b&#x2009;=&#x2009;0.18, p&#x2009;=&#x2009;.48). GNT-W did not confer additional benefit over EW protocol on PTSS severity.Conclusions: Both self-directed writing interventions were associated with within-group reductions in PTSS; without an inactive control condition, however, these changes cannot be firmly attributed to the interventions. GNT-W showed no advantage over the simpler EW protocol. These findings offer preliminary support for embedding scalable, low-barrier writing interventions in widely used digital platforms.Chinese Clinical Trial Registry: ChiCTR2000034836.

Humans

Stroke risk following BNT162b2 vaccination: a systematic review and meta-analysis of self-controlled case series studies.

INTRODUCTION: Whether BNT162b2 (Pfizer-BioNTech) vaccination increases stroke risk remains a public health concern. This is the first meta-analysis to synthesize self-controlled case series (SCCS)-derived stroke risk estimates specifically for BNT162b2 vaccination. METHODS: PubMed and Embase were searched from inception through 9 May 2026, following PRISMA 2020 guidelines. Eight eligible SCCS studies were pooled using a random-effects model with restricted maximum likelihood (REML) estimation and the Knapp-Hartung adjustment. RESULTS: Eight studies across six countries encompassing several million vaccinated individuals were included. The pooled incidence rate ratio (IRR) was 0.967 (95% CI 0.892-1.049; I2&#x2009;=&#x2009;69.2%), indicating no statistically significant increase in stroke risk. Subgroup analyses showed no evidence of effect modification across continent, risk-window length, dose category, SCCS variant, or age group. CONCLUSIONS: These findings provide no evidence of increased short-term stroke risk following BNT162b2 vaccination at the population level. The observed heterogeneity appeared to be partly driven by methodological differences rather than true biological variation in vaccine effect.

Humans