When mice were exposed to one of these lab-created berbugs, they contracted the massive lung infections and hemorrhages typical of the 1918 flu. The lethal ingredient turned out to be hemagglutinin, a protein that helps the virus attach to cells during infection. Some scientists hailed the discovery, which they said will make
it easier to identify early signs of an emerging superbug and prevent its return. Other, less sanguine scientists point out that the 1918 strain might never reappear and that re-creating it has put humanity at risk. Although most influenza strains are unlikely bioweapons, this extra-lethal one might be turned to that purpose. It now resides in a high-security lab in Madison, Wisconsin. One accident, or one lab worker bent on sabotage, and we could have another epidemic --sparked this time not by nature but by our desire to outsmart it.