Three-pronged designed peptide neutralizes influenza

If you want to thwart infection by influenza viruses, a good bet is to block the pathogen’s exterior hemagglutinin proteins from binding with a host cell’s sialic acid-containing sugars. Nature already uses this interference strategy: Antibodies bind influenza hemagglutinin, preventing infection by obstructing the host-pathogen interaction in a variety of ways, sometimes at the sialic acid binding site and other times with just the antibody’s sheer physical bulk. This bulk has its downside, though: Only . . .