The risk of transmission of SARS-CoV-2 through blood and blood products: The current state of knowledge (international review)

Abstract

Introduction: Severe acute reparatory syndrome coronavirus-2 (SARS-CoV-2) is a recently emerged coronavirus, and infection with SARS-CoV-2 can remain asymptomatic or lead to coronavirus infection disease. Clinical pictures range from a pre-clinical stage to severe pneumonia. The presence of this pre-clinical infection stage could pose a problem for the management of the transfusion chain as donors or employees may become infected during their travels or activities, and this may exponentially increase the number of infected but asymptomatic individuals. So, SARS-CoV-2 may pose a threat to blood safety. Aim: In this study, we want to provide the necessary information about the real risk of transmission of SARS-CoV-2 via blood and blood products. It constitutes one of the most controversial topics with several critical questions for which both professionals in blood centers and health services seek apparent answers. Methods: It is a literature review where we have consulted relevant papers and articles about the real risk of transmission of SARS-CoV-2 through blood or blood products. For this purpose, scientific research sites were consulted using key terms search strategy. Thus, we compiled and presented the necessary information from (i) positions of international scientific societies and public bodies; (ii) available data to date on detecting SARS-CoV-2 RNA in the blood of COVID-19 patients and blood donors; and (iii) published cases of transfusion of blood products from donors confirmed COVID-19 positive after donation and the process in recipients of these products. Results: All papers published to date stipulated that SARS-CoV-2 is a new infectious agent. No sufficient information is available to exclude with certainty the risk of transfusion transmission, which remains a theoretical risk. SARS-CoV-2 RNA has been detected very lowly, but virus infectivity has not been confirmed in blood donors. Reported cases of product transfusion from COVID-19 positive donors after a donation have not provided any evidence of transmission of the virus to recipients. As a precautionary measure, blood transfusion centers have set up necessary measures to reduce the risk of transmission of SARS-CoV-2 through blood products and ensure the safety of donors and recipients. Strengthening the hemovigilance system and post-donation information is an essential link for blood safety during the COVID-19 pandemic. Conclusion: All data available to date stipulated that SARS-CoV-2 is not transfusion-transmitted and that the risk of transmission of this new coronavirus through blood and blood products is still theoretical. This novel coronavirus may be no direct threat to blood safety but raises serious issues for general blood supply. All measures taken by blood centers to secure blood donation against this new virus are preventive measures that should consider the need to ensure the availability of blood products.