Influenza A virus infection has rarely been documented to cause viremia. In 28 blood donations in Brazil that were deferred because of postdonation information, we identified influenza A(H3N2) virus RNA in 1 donation using metagenomic analysis. Our finding implies theoretical risk for viremia and transfusion transmission.
Keywords: H3N2; Influenza A; RNA; blood donations; influenza; respiratory infections; viral metagenomics; viruses.