
At the moment, influenza, or “flu” is a disease which kills many thousands of people despite the availability of a different vaccine every year. A new flu vaccine has to be manufactured each year to accommodate the changes that are seen in the flu virus. The virus mutates, which means different antibodies are needed to recognise it.
The parts of the flu virus which mutate are surface proteins called haemagglutinins. These haemagglutinin proteins are composed of a “head” and a “stem” region....