No changes in hemostasis after COVID-19-heterologous vaccination schedule: A subanalysis of the phase 2 CombiVacS study.

Background: Several cases of unusual thrombotic events and thrombocytopenia were described after vaccination with recombinant adenoviral vectors encoding the spike protein antigen of SARS-CoV-2. Objectives: The objective of this study was to elucidate the impact of a COVID-19 heterologous vaccination schedule, including priming with adenovirus vaccine, on hemostasis profiles. Methods: The present study is a subanalysis of the CombiVacS clinical trial initiated in April 2021 that included adult participants previously vaccinated with a single dose of ChAdOx1-S. Between 8 and 12 weeks after vaccination, they were randomly assigned (2:1) to receive either BNT162b2 vaccine (intervention group, n = 99) or continue observation (control group, n = 50). Samples drawn before and 28 days after a vaccination with BNT162b2 were analyzed for platelet count and markers of hemostasis (D-dimer, anti-PF4 antibodies, cfDNA, PAI-1, thrombin generation, and serum capacity to activate platelets). Results: Platelet count from all participants after receiving BNT162b2 was within the normal range. Anti-PF4 antibodies were present in 26% and 18% of the subjects from the control and intervention groups, respectively, at day 28. In most cases, the levels of anti-PF4 antibodies were high before receiving BNT162b2. Serum from these participants did not activate platelets from healthy controls. There were no differences between the groups in PAI-1 and cfDNA plasma levels. According to the D-dimer plasma concentration, the thrombin generation test showed that none of the participants had a procoagulant profile. Conclusion: Our data suggest that the heterologous vaccination against COVID-19 with ChAdOx1-S and a second dose with BNT162b2 might be safe in terms of haemostasis.

Effect of the first year of COVID-19 pandemic on the collection and use of blood components in Colombia monitored through the national haemovigilance system.

OBJECTIVE: This work aimed to establish the effects of the COVID-19 pandemic on blood collection and blood product usage at the end of the first year. BACKGROUND: The arrival of SARS-CoV-2 to Colombia on March 6, 2020, triggered closure of borders and mandatory lockdown from March 23, 2020. METHODS/MATERIALS: The Colombian National Institute of Health administers the National database of confirmed cases of SARS-CoV-2 and the National Haemovigilance System. We examined positive SARS-CoV-2 cases identified between March 6, 2020, and March 6, 2021, using positive RT-PCR testing (72.8%) or reactive antigen (27.2%). We also analysed accepted and deferred donors' information provided by 100% of blood banks and transfused patients notified by 83% of health care facilities nationwide, between March 1, 2019, to February 28, 2021. RESULTS: Colombia registered 2 273 245 SARS-CoV-2 cases. From these, 60 412 people died from COVID-19 (2.7%) and 2 172 418 individuals recovered (95.6%). There were 11 659 216 SARS-CoV-2 processed samples nationwide. People between the ages of 20 and 39 years concentrated 44.4% of the SARS-CoV-2 cases. There were 773 569 blood donations, mainly from a 20-39-year-old population (60.5%). The pandemic caused a reduction of 155 393 blood donations (16.7%) and 51 823 total deferrals (33.7%). An 18.4% drop in volunteer donors and a 37.3% increase in donations from family/replacements members were observed. There were 399 453 transfused patients and 1 179 895 blood components administered (-8.7% and - 13.9% compared to March 2019-February 2020). CONCLUSION: Mandatory lockdowns in Colombia decreased blood collection and usage, resulting in a reduction of blood components transfused to individual patients.

Registry of patients with congenital bleeding disorders and COVID-19 in Madrid.

INTRODUCTION: We present the first registry of patients with congenital bleeding disorders and COVID-19. The study has been carried out in the Community of Madrid, which has the highest number of cases in Spain. The objective is to understand the incidence of COVID-19, the course of the disease if it occurs and the psychosocial and occupational impact on this population. METHODS: We included 345 patients (246 of haemophilia, 69 of von Willebrand Disease, two rare bleeding disorders and 28 carriers of haemophilia). A telephone survey was used to collect the data. RESULTS: Forty-two patients presented symptoms suggestive of infection by COVID-19, and in six cases, the disease was confirmed by RT-PCR. The cumulative incidence of our series was 1.73%. It is worth noting the complexity of the management of COVID-19 in two patients on prophylaxis with non-factor replacement therapy. Adherence to the prescribed treatment was maintained by 95.5% of patients. Although 94% were independent for daily living activities, 42.4% had a recognized disability and 58% required assistance, provided by the Madrid Haemophilia Association (Ashemadrid) in 75% of cases. Only 4.4% of consultations were held in person. CONCLUSIONS: Patients with congenital bleeding disorders infected with SARS-CoV-2 presented a mild course of the disease that did not require admission. Their identification and treatment by a specialist team from a Haemophilia Treatment Center are essential to make a correct assessment of the risk of haemorrhage/thrombosis. COVID-19 had a major impact on the psychosocial aspects of these patients which must be remedied with recovery plans.