If H5N1 Evolves

I worked on bird flu in a laboratory in London in the 1960s. We called it KP, short for klassische Geflügelpest. The boss was an ardent Germanophile, but this wasn’t the only reason. He wanted us to remember Werner Schäfer’s discovery in 1955 in Tübingen that KP, fowl plague, was an influenza virus, and Shäfer’s suggestion that such bird viruses might have the ability to change and infect other species. It was feared by chicken farmers. It spread rapidly in flocks and was a killer. Birds at the near end of a hen-house would all be dead, those in the middle dying, some with swollen heads and diarrhoea and others just falling without warning, while those at the far end looked healthy but were doomed to drop within the day.