In a comprehensive genetic study, scientists have found what they say is the strongest evidence yet linking the first European explorers of the New World to the origin of sexually transmitted syphilis.
The research, they say, supports the hypothesis that returning explorers introduced organisms leading, in probably modified forms, to the first recorded syphilis epidemic, beginning in Europe in 1493.
The so-called Columbus hypothesis had previously rested on circumstantial evidence, mainly the timing of the epidemic. It was further noted that earlier traces of syphilis or related diseases had been few and inconclusive in Europe. Yet nonvenereal forms of the diseases were widespread in the American tropics.
Leaders of the new study said the most telling results were that the bacterium causing sexually transmitted syphilis arose relatively recently in humans and was closely related to a strain responsible for the nonvenereal infection known as yaws. The similarity was especially evident, the researchers said, in a variation of the yaws pathogen isolated recently among afflicted children in a remote region of Guyana in South America.
Not quite a slam dunk but pretty powerful.
UPDATE: Hawks has a post on it. He mentions that one of the major significant findings is not only the source of syphilis but the fact that it evolved so quickly; it "fundamentally changed its nature, with increased virulence and sexual transmission". Indeed.