June 4, 2026

COVID: Active Vaccination/Immunity

El Impact of COVID-19 Vaccination on Long-term Risk of New-onset Atrial Fibrillation/Flutter after COVID-19 Infection: A Retrospective Cohort Study
These results come from a retrospective cohort study using the TriNetX Research Network. They looked at the potential protective effect of COVID-19 vaccination against long-term new-onset atrial fibrillation/flutter (NOAF) risk following COVID-19 infection. The 24-month NOAF incidence was significantly lower in the vaccine group compared to the control group (1.91% vs 2.18%; HR: 0.82, 95% CI: 0.78–0.85). This protective effect was also observed at one month (HR: 0.73, p < 0.001), six months (HR: 0.71, p < 0.001), and 12 months (HR: 0.77, p < 0.001). Sensitivity analysis confirmed these findings (HR: 0.79 at 24 months). Subgroup analyses demonstrated that COVID-19 vaccination provided significant protection against NOAF across all examined subgroups, with younger patients (18–60 years) showing greater risk reduction compared to older individuals.

COVID: Early Viral Phase

Convalescent Plasma for People with COVID-19
In this review authors searched for completed and ongoing studies, (CENTRAL, MEDLINE, Embase, the Epistemonikos COVID‐19 L*OVE Platform), and clinical trial registries to October 2024. The Epistemonikos COVID‐19 L*OVE Platform was established by the Epistemonikos Foundation and is a repository with over 6,000 pandemic-related articles, including all systematic reviews, as well as every primary study and all other kinds of articles. Authors report they are “very confident” that plasma from the blood of people who have recovered from COVID‐19 (convalescent plasma) does not help people with moderate to severe COVID‐19. Convalescent plasma may make little or no difference to people with mild COVID‐19. More evidence is needed about people with mild COVID‐19, those with no symptoms, and those with a weaker immune system.