Why the Black Death was the mother of all plagues
Plague germs teased from mediaeval cadavers in a London cemetery have shed light on why the bacterium that unleashed the Black Death was so lethal and spawned later waves of epidemics. - The DNA of Yersinia pestis shows, in evolutionary terms, a highly successful germ to which the population of 14th-century Europe had no immune defences, according to a study published Wednesday in the British journal Nature. It also lays bare a pathogen that has undergone no major genetic change over six centuries.