The Entwined Destinies of Mankind and Leprosy Bacteria

Leprosy still affects hundreds of thousands of people today throughout the entire world. An international team headed by EPFL professor Stewart Cole has traced the history of the disease from ancient Egypt to today and in doing so has made a public health study essential for combating the disease. For thousands of years an undesirable and persistent companion has been travelling with man wherever he goes. Mycobacterium leprae, the bacterium that causes leprosy, has only one known natural host - mankind. And because of man's many travels, this bacillus has colonized the entire earth. Its history is therefore intimately tied to our own, and it is this migratory relationship that Stewart Cole, EPFL professor of Microbial Pathogenesis, and his team have analyzed. Geneticists, microbiologists, and even archeologists have followed the bacteria's traces from their lab to the Silk Road and the tombs of Egyptian mummies. The scientists started with the past history of the disease by investigating the remains of English, Croatian, and Bulgarian medieval cemeteries along with an ancient Egyptian burial site to find traces of the bacteria's DNA. "A person infected with the bacteria shows specific signs of bone deformations, like hands gripped closed in the form of a claw," explains Steward Cole, "and these clues helped us determine if we were dealing with the bodies of people who died from the disease." In the wake of commercial ships