[COVID-19 - BLOOD GROUPS, ANTIBODIES AND CONVALESCENT PLASMA]

Israel is currently struggling with the Coronavirus Disease (COVID-19) caused by SARS CoV-2. Transmission is increasing, with higher morbidity and mortality among populations at risk. Over-representation of blood type A was reported in COVID-19 patients with increased respiratory failure, while blood type O seems to have a protective effect. This may be caused by interference of anti-A antibodies in viral binding to the ACE receptor, different neutralization antibodies potency or variations in the stability of von Willebrand factor (VWF) multimers in different blood types. Since transfusion of convalescent COVID19 Plasma (CCP) is an accepted therapeutic modality, the Ministry of Health initiated a national project whereby CCP is collected by Magen David Adom (MDA) Blood Services using apheresis procedures and transfusions are approved by an experts committee, as part of the clinical trial or as compassionate treatment. Preliminary analysis of 49/170 patients treated so far shows improvement in 49%, with important relations with the anti-SARS-CoV-2 IgG antibodies level in the transfused plasma. Anti-SARS-CoV-2 antibodies were found in 83% of 1100 CCP donors, but a 13% decrease in antibodies level was detected in repeat donations. Blood type A was more predominant among CCP donors, when compared to MDA blood donors' data. A transfusion of CCP is a feasible and relatively safe therapeutic modality, mainly for patients with moderate COVID 19. CCP also serves as a source for the production of hyperimmune globulin for the treatment of COVID 19 and for passive immunization for populations at risk.