October 8, 2026

Vaccination

Vaccine-Preventable Infectious Disease Mortality Among Children in the Post-vaccine Era: Persistent Burden and Emerging Temporal Trends
This study evaluated temporal trends, disease-specific mortality patterns, and demographic disparities in childhood mortality due to vaccine-preventable infectious diseases over 25 years. A total of 5,520 deaths due to vaccine-preventable infectious diseases were identified, corresponding to an overall crude mortality rate of 0.29 per 100,000 children. Mortality declined initially but subsequently fluctuated without a sustained downward trend. Influenza accounted for 60.7% of all deaths and was the only disease demonstrating a significant increase in mortality over time. Significant declines were observed in pneumococcal disease mortality, meningococcal disease mortality, and infant mortality, whereas mortality among children aged five to nine years increased significantly. Negative binomial regression demonstrated significantly higher adjusted mortality rate ratios among American Indian or Alaska Native and Black or African American children compared with White children.

Influenza

Adjuvanted and High-dose Influenza Vaccines Had Comparable Effectiveness Against Test-confirmed Influenza Outcomes Including Hospitalizations in Overall and High-risk Older Adults in the 2022–2023 and 2023–2024 Seasons
These are the results of a retrospective test-negative design study that included U.S. adults aged ≥65 years vaccinated with aQIV or HD-QIV who presented with acute respiratory or febrile illness and were tested for influenza per routine care. aQIV and HD-QIV provided comparable protection for prevention of test-confirmed influenza among older adults in any ED/hospitalization settings in the 2023–2024 season and for hospitalizations in overall and high-risk older adults in pooled 2022–2024 analyses.

Influenza vaccine effectiveness against influenza A-associated hospitalization and severe in-hospital outcomes among adults in the United States, 2024–2025
The U.S. 2024–2025 influenza season was characterized by sustained elevated activity from November 2024–April 2025, with circulation of both influenza A(H1N1)pdm09 and A(H3N2), the latter of which included some antigenically drifted viruses. From October 1, 2024, to April 30, 2025, a multistate respiratory virus surveillance network enrolled adults hospitalized with acute respiratory illness in 26 U.S. medical centers. Influenza vaccine effectiveness (VE) against influenza-associated hospitalization and severe in-hospital outcomes was estimated using a test-negative study. The 2024–2025 seasonal influenza vaccine was effective against influenza-associated hospitalization (VE: 40% [95% confidence interval (CI): 32%–47%]), consistent across age group and influenza type/A subtype. Influenza vaccination also reduced the overall risk of all severe in-hospital outcomes evaluated, including standard oxygen therapy (VE: 41% [95% CI: 31%–50%]), non-invasive advanced respiratory support (VE: 38% [95% CI: 19%–52%]), invasive organ support (VE: 58% [95% CI: 44%–69%]), ICU admission (VE: 58% [95% CI: 47%–67%]), and death (VE: 52% [95% CI: 18%–71%]) with effectiveness varying by influenza A subtype and age.

COVID: Active Vaccination/Immunity

Temporary Cessation of DMARD Therapy and COVID-19 Supplemental Dose Vaccine Immunogenicity in Patients With Inflammatory Arthritis The COVER Randomized Clinical Trial
In this multicenter randomized clinical trial of 840 patients with inflammatory arthritis, temporarily holding biologic or JAK inhibitor therapy for two weeks did not improve anti–receptor-binding domain immunoglobulin G antibody responses (geometric mean fold rise ratio, 0.96; 95% CI, 0.36-2.56) but was associated with significantly higher odds of disease flare (odds ratio, 2.27; 95% CI, 1.41-3.65) following a supplemental vaccine dose. Meaning The findings of this randomized clinical trial do not support routine temporary interruption of biologic or JAK inhibitor therapy for COVID-19 vaccine immunogenicity optimization in patients with inflammatory arthritis.

Prophylactic vs Therapeutic Anticoagulation in Hospitalized Patients With COVID-19 A Randomized Clinical Trial
This prospective, assessor-blinded, multicenter, parallel-group (1:1), placebo-controlled, superiority randomized clinical trial (HERO-19) sought to address the question: Can therapeutic anticoagulation plus standard of care improve clinically relevant outcomes in hospitalized patients with COVID-19? Study assessed patients with a confirmed diagnosis of COVID-19 who were hospitalized in an intensive care unit or non–intensive care ward at one of 10 university hospitals in Germany from November 12, 2020, to January 15, 2023. A total of 139 patients (mean [SD] age, 58.4 [13.7] years; 93 [67%] male and 46 [33%] female) were included in the study. This trial found that in-hospital therapeutic anticoagulation with low-molecular weight heparin followed by edoxaban was well tolerated but did not statistically significantly reduce death and/or thromboembolic events compared with prophylactic anticoagulation followed by placebo. These findings do not support routine therapeutic anticoagulation in hospitalized patients with COVID-19 to reduce death or thromboembolic events compared with prophylactic anticoagulation.