Pandemic blood donor demographics - Do changes impact blood safety?

COVID-19 safety measures and possibly SARS-CoV-2 antibody testing may alter blood donor demography, which has the potential to alter blood safety. We characterized pre-pandemic and pandemic rates of donor infectious disease marker (IDM) reactivity which reflect the residual risk of transfusion-transmitted infections (TTIs) undetectable by current testing.

This cross-sectional analysis of allogeneic blood donor presentations and successful donations in a large national US blood collector identifies changes in self-reported behavioral risk factors and IDM reactivity. Data on allogeneic blood donor presentations and successful donations from March 1 through August 31, 2020 and the same period in 2019 were retrieved from the blood center's computer system. Donor demographics and deferrals for reported behavioral risk factors and confirmed-positive IDMs were compared in pre-pandemic and pandemic periods.

With increasing mobile blood drive cancellations, pandemic donors were more likely than 2019 donors to be female, over age 30, non-Hispanic Whites, and have a post-secondary degree. First-time donations (at highest risk for confirmed-positive IDMs) did not substantially increase. Pandemic donors reported fewer behavioral risks and IDMs declined among these donors. Mid-pandemic introduction of screening for SARS-CoV-2 antibodies did not affect IDM rates.

Unlike disasters, which tend to bring out more first-time donors with increased IDM reactivity and TTI residual risk, COVID-19 donors had lower IDM rates which were not affected by SARS-CoV-2 antibody testing. Already-low TTI residual risk is likely to have declined as a result.