Background Despite several publications covering patients from multiple centers, no international registry covered all patients with red blood cell diseases (RBCD) affected by COVID-19. The ERN-EuroBloodNet’s registry provided real-time registration of SARS-CoV-2 patients with RBCD, promoting timely disease-specific knowledge sharing during the pandemic’s early stages. Procedures The study evaluated patient distribution, the infection across different RBBDs, and severity risk factors across similar healthcare systems, using data collected from the ERN-EuroBloodNet’s REDCap platform. Results From April 2020 to April 2023, 681 infections were recorded among 663 patients, of which 373 had transfusion-dependent thalassemia or non-transfusion-dependent thalassemia (TDT/NTDT), and 269 had sickle cell disease (SCD). SCD patients had a higher incidence of COVID-19 than those with TDT/NTDT (10.5 vs. 4.8 COVID/100 patients). Notably, 92% of the cases were mild, with neither age nor the specific RBCD affecting severity. The number of comorbidities, notably obesity and hypertension, that patients had prior to infection was associated with more severe COVID-19. During the infection, the presence of vaso-occlusive crises, acute chest syndrome, kidney failure, and ground-glass opacities on chest tomography scans were associated with a more severe clinical picture. The vaccination rate (32%) mirrored that of the general population and showed a protective effect against severe COVID-19. The observed mortality rate was 0.7%, aligning with Europe’s general population. Conclusion: SARS-CoV-2 infection in SCD and TDT/NTDT patients is mild and without higher mortality than the general population. The ERN-Eurobloodnet’s registry collaborative structure exemplifies the power of international cooperation in tackling rare diseases, especially during health emergencies

Background: The COVID-19 pandemic led to an increase in research activity worldwide. The Vall d’Hebron University Hospital Research Ethics Committee (VH-REC) adapted its procedures to give out the opinion rapidly. We aimed to describe the characteristics of the VH-REC activity and studies evaluated during the first outbreak. Methods: Clinical trials (CT), post-authorization studies (PAS) and research projects (RP) on COVID-19 were included and followed up. Variables were described through usual descriptive methods. Results: 157 studies were evaluated: 10 CT, 16 PAS and 131 RP, in 25 bi-weekly online meetings. Non-commercial, unicentric and national studies predominated (95%, 54% and 88%, respectively). The main objective of CT and PAS studies was to test efficacy and safety, and for RP to describe patients’ outcomes. Some studies focused on specific interest groups, such as healthcare professionals or immunosuppressed patients (10% both). The median time of protocols’ evaluation was 3 days. 58.6% (92) required further clarifications, mainly due to aspects of data protection, informed consent, and biological samples. The final opinion was favourable in 93% (146). Regarding follow-up, 123 studies had been initiated and 64 also finalized. Results have been published in 59% (51) of studies. Conclusions and implications: COVID-19 pandemic has led to greater academic and local research, especially through research projects. Electronic sources were implemented for evaluation shortening and ease follow-up. These measures should remain to streamline VH-REC processes, and trends to publish results favoured. This study could allow comparisons with other activity periods (e.g. pre or post-pandemic), or with other REC’