Managing potential risk of transfusion transmitted SARS-CoV-2 to cancer patients

ABSTRACT

Background/Case Studies Available scientific evidence of transmission, incubation, clinical and laboratory evolution of COVID-19 from other countries was very worrisome. This virus has an unknown, potential, or confirmed risk of blood transfusion transmission and there is a lack of information if cancer patients are at higher risk. Therefore, we decided to implement more restrictive rules for clinical screening of blood donors, trigger retrospective screening tests after post-donation notification of infection, and perform the transfused patients follow up. Here we evaluate results from 140 days period of implemented actions in a cancer center blood bank in Brazil. Study Design/Methods: Number of blood donation candidates, non-eligible donors due to risk of COVID-19, post-donation notifications and impact in receipt patients were retrospectively evaluated. Clinical screening included questions if candidates were in regions with local transmission of disease, contact with people with COVID-19 and if they had clinical or laboratory diagnosis of COVID-19. Donors were instructed to report any signs or symptoms of infections within fourteen days after donation. After any post-donation notification, all blood products from last donation were immediately traced if still in stock, they were segregated;if any was transfused, frozen blood sample from these donors, collected on the same day of blood donation, were tested for SARS-COV2RT-PCR and patients were submitted to a close clinical follow up. Results/Findings: Data from Feb 27 to Jul 15, 2020 included 6288 blood donation candidates. Out of them, 31 (0.49%) were non-eligible to blood donation due to COVID-19 risk at screening. Post-donation notifications had one of contact with people with COVID-19, and nine notifications of flu-like symptoms within less than two weeks from donation, with six confirmed RT-PCR positive (0.09%). All blood products were traced and eight were transfused - two platelet apheresis, one red blood cell, and five random platelets. Available frozen blood samples from these donors were tested negative for SARS-CoV-2 RT-PCR and, due to these negative results, not all patients were tested for COVID-19 but had close clinical follow up. One patient had RT-PCR positive 5 days after transfusion, but no correlation to blood transfusion was confirmed. Conclusions: Further investigation is needed to better understand the potential risk of blood transfusion transmission of COVID-19, mainly for cancer patients. Clinical screening of blood donation candidates is the main tool at this moment to reduce risk of virus transmission since there is no regulation for testing all blood donors. In addition, donors' commitment to post-donation information is very important, reducing the risk of transfusion transmission of COVID-19.