A new study challenges the long-held belief that Christopher Columbus and his Spanish expedition introduced syphilis to Europe from the Americas in the late 15th century. Past research on medieval bones suggested the presence of the syphilis-causing bacterium Treponema pallidum or related strains in Europe before Columbus's return in 1493. The latest study, led by a team of paleomicrobiologists, adds weight to this counter-hypothesis by identifying signs of a T. pallidum infection in a 7th or 8th-century French thigh bone.
Excavated in 1987 at Chapelle Saint-Vincent in Roquevaire, France, the diseased femur was found among other bones. The researchers extracted fragmented DNA resembling a portion of the T. pallidum reference genome and detected antibodies specific to T. pallidum in the infected femur. According to the researchers, these findings challenge a century-old dogma in medical microbiology, pushing back the potential presence of T. pallidum infections in Europe by eight centuries.
However, not all historians are convinced, as there is no historical evidence of syphilis outbreaks before the 1490s in Europe. Different subspecies of Treponema bacteria cause various diseases, with T. pallidum pertenue causing yaws and T. pallidum endemicum causing bejel. The researchers cannot definitively conclude that the infection in the ancient bone caused syphilis, leaving room for debate.
While the damaged DNA from the 1,400-year-old bone covered only 2.4 per cent of the pallidum subspecies genome, it closely resembled those sections. Some medical experts suggest that while evidence points to the presence of pertenue or endemicum in Europe before Columbus's return, the infectious strain pallidum might have arrived from the Americas.
The study adds a complex layer to the origins of syphilis, challenging the conventional narrative associated with Columbus's voyages. The evolving understanding of the disease's history may require further evidence to clarify the role of different Treponema subspecies and their potential spread across continents.