Growing evidence suggests that ABO blood group may play a role in the immunopathogenesis of SARS‐CoV‐2 infection, with group O individuals less likely to test positive and group A conferring a higher susceptibility to infection and propensity to severe disease. The level of evidence supporting an association between ABO type and SARS‐CoV‐2/COVID‐19 ranges from small observational studies, to genome‐wide‐association‐analyses and country‐level meta‐regression analyses. ABO blood group antigens are oligosaccharides expressed on red cells and other tissues (notably endothelium). There are several hypotheses to explain the differences in SARS‐CoV‐2 infection by ABO type. For example, anti‐A and/or anti‐B antibodies (e.g. present in group O individuals) could bind to corresponding antigens on the viral envelope and contribute to viral neutralization, thereby preventing target cell infection. The SARS‐CoV‐2 virus and SARS‐CoV spike (S) proteins may be bound by anti‐A isoagglutinins (e.g. present in group O and group B individuals), which may block interactions between virus and angiotensin‐converting‐enzyme‐2‐receptor, thereby preventing entry into lung epithelial cells. ABO type‐associated variations in angiotensin‐converting enzyme‐1 activity and levels of von Willebrand factor (VWF) and factor VIII could also influence adverse outcomes, notably in group A individuals who express high VWF levels. In conclusion, group O may be associated with a lower risk of SARS‐CoV‐2 infection and group A may be associated with a higher risk of SARS‐CoV‐2 infection along with severe disease. However, prospective and mechanistic studies are needed to verify several of the proposed associations. Based on the strength of available studies, there are insufficient data for guiding policy in this regard.

Background and objectives COVID‐19 convalescent plasma (CCP) has been used, predominantly in high‐income countries (HICs) to treat COVID‐19; available data suggest the safety and efficacy of use. We sought to develop guidance for procurement and use of CCP, particularly in low‐ and middle‐income countries (LMICs) for which data are lacking. Materials and methods A multidisciplinary, geographically representative group of individuals with expertise spanning transfusion medicine, infectious diseases and haematology was tasked with the development of a guidance document for CCP, drawing on expert opinion, survey of group members and review of available evidence. Three subgroups (i.e. donor, product and patient) were established based on self‐identified expertise and interest. Here, the donor and product‐related challenges are summarized and contrasted between HICs and LMICs with a view to guide related practices. Results The challenges to advance CCP therapy are different between HICs and LMICs. Early challenges in HICs related to recruitment and qualification of sufficient donors to meet the growing demand. Antibody testing also posed a specific obstacle given lack of standardization, variable performance of the assays in use and uncertain interpretation of results. In LMICs, an extant transfusion deficit, suboptimal models of donor recruitment (e.g. reliance on replacement and paid donors), limited laboratory capacity for pre‐donation qualification and operational considerations could impede wide adoption. Conclusion There has been wide‐scale adoption of CCP in many HICs, which could increase if clinical trials show efficacy of use. By contrast, LMICs, having received little attention, require locally applicable strategies for adoption of CCP.

Background and Objectives The coronavirus disease 2019 (COVID‐19) pandemic has impacted blood systems worldwide. Challenges included maintaining blood supplies and initiating the collection and use of COVID‐19 convalescent plasma (CCP). Sharing information on the challenges can help improve blood collection and utilization. Materials and Methods A survey questionnaire was distributed to International Society of Blood Transfusion members in 95 countries. We recorded respondents' demographic information, impacts on the blood supply, CCP collection and use, transfusion demands and operational challenges. Results Eighty‐two responses from 42 countries, including 24 low‐ and middle‐income countries, were analysed. Participants worked in national (26.8%) and regional (26.8%) blood establishments and hospital‐based (42.7%) institutions. CCP collection and transfusion were reported by 63% and 36.6% of respondents, respectively. Decreases in blood donations occurred in 70.6% of collecting facilities. Despite safety measures and recruitment strategies, donor fear and refusal of institutions to host blood drives were major contributing factors. Almost half of respondents working at transfusion medicine services were from large hospitals with over 10,000 red cell transfusions per year, and 76.8% of those hospitals experienced blood shortages. Practices varied in accepting donors for blood or CCP donations after a history of COVID‐19 infection, CCP transfusion, or vaccination. Operational challenges included loss of staff, increased workloads and delays in reagent supplies. Almost half of the institutions modified their disaster plans during the pandemic. Conclusion The challenges faced by blood systems during the COVID‐19 pandemic highlight the need for guidance, harmonization, and strengthening of the preparedness and the capacity of blood systems against future infectious threats.