July 31, 2025

Influenza

Effects of Baloxavir Marboxil Plus Neuraminidase Inhibitor versus Neuraminidase Inhibitor in High-risk Patients Hospitalized with Severe Influenza: A Post Hoc Analysis of the Flagstone Trial
Eligible participants met at least one of the following criteria: immunosuppression, diabetes, or chronic lung diseases. Time to clinical improvement (TTCI), 28-day mortality, virological outcomes, and safety endpoints were assessed. Among the 143 patients included in the efficacy analysis, 92 received baloxavir in combination with NAI (dual antiviral group), while 51 received NAIs alone (mono antiviral group). In patients infected with influenza A H3N2, the TTCI was significantly shorter in the dual compared to mono antiviral group (median 97.53 h vs 172.42 h. The dual antiviral group demonstrated significantly lower mortality compared to the mono antiviral group (2 [2.17%] of 92 vs 6 [11.76%] of 51; p=0.02), and was associated with a shorter time to cessation of viral shedding (p<0.001).

COVID: Active Vaccination/Immunity

Safety of JN.1-Updated mRNA COVID-19 Vaccines
All adults in Denmark recommended to receive the 2024-2025 JN.1-containing booster vaccine (ie, those aged ≥65 years or individuals in high-risk groups) who had previously received three or more COVID-19 vaccine doses were included. The study period ran from May 1, 2024, to March 31, 2025. Investigators analyzed 29 adverse outcomes adapted from prioritized lists of adverse events of special interest to COVID-19 vaccines. Outcome rates during the first 28 days after JN.1-containing vaccine administration (ie, the risk period) were compared with outcome rates during the remaining period (ie, the reference period, with follow-up from the study start or ≥43 days after any prior dose or the JN.1-containing vaccine dose). The cohort totaled 1, 585, 883 individuals (mean [SD] age, 66.8 [14.5] years; 862 585 female [54.4%]), of whom 1, 012, 400 individuals (mean [SD] age, 73.5 [10.3] years) received updated mRNA COVID-19 vaccines containing the JN.1 lineage vaccine during follow-up. No statistically significant increases in the rate of hospital contacts for any of 29 adverse events were observed during the 28-day risk period after receipt of a JN.1-containing mRNA vaccine compared with reference period rates .

COVID: The Late Phase/PASC/Long COVID

Prevalence of Persistent Cardiovascular and Pulmonary Abnormalities on PET/MRI and DECT Imaging in Long COVID Patients
The objective of this study was to describe the prevalence of inflammatory cardiopulmonary findings in a prospective cohort of Long Coronavirus disease (LC) patients. Subjects with a history of COVID-19 infection, persistent cardiopulmonary symptoms 9–12 months after initial infection, and a clinical assessment compatible with LC underwent cardiopulmonary 18F-FDG PET/MRI, dual-energy CT (DECT) of the lungs, and plasma protein analysis (in a subgroup). A control group that included subjects with a history of acute severe acute respiratory syndrome Coronavirus 2 infection but without cardiopulmonary symptoms at recruitment was also characterized. Ninety-eight patients (median age, 48.5 y; 47% men) were enrolled. The most common LC symptom was shortness of breath (80%), and 27% of participants were hospitalized. Of the subjects, 90% presented abnormalities in DECT, with 67% and 59% of participants demonstrating pulmonary infiltrates and abnormal perfusion, respectively. PET/MRI was abnormal for 57% of subjects: 24% showed cardiac involvement suggestive of myocarditis, 22% presented uptake reminiscent of pericarditis, 11% showed periannular uptake, and 30% showed vascular uptake (aortic or pulmonary). There was no myocardial, pericardial, periannular, or pulmonary uptake on the PET/MRI scans of the control group (n = 9). Analysis of plasma protein concentrations showed significant differences between the LC and the control groups. Lastly, the plasma protein profile was significantly different among LC patients with abnormal and normal PET/MRI.