Scientists have uncovered the structure of 1918 flu virus

Scientists at the Medical Research Council have discovered the crucial structural changes the avian influenza virus underwent that resulted in its killing 20 million people worldwide in 1918—more people than were killed in the first world war and making it the largest pandemic in history.

The study, published last week in the online version of Science (5 February; http://dx.doi.org/10.1126/science.1093155), found that subtle alterations to the shape of a protein molecule, called haemaglutanin (HA), on the virus allowed transmission from birds to humans, …