BRD2 and syphilis: The following tests are performed on all blood units collected since 2002: tests for TTIs by ELISA prior to the introduction of NAT tests in the routine screening (HIV1 + 2 antibodies and p24 antigen for HIV, HBsAg for HBV, anti-HCV antibodies for HCV, and VDRL and TPHA for syphilis); blood grouping (ABO red cell and serum grouping, rhesus D grouping); and rhesus phenotype and screening tests for irregular blood group antibodies.