Columbus has been exonerated of the claim that he was the one who introduced the sickness called syphilis to Europe, according to scientists.
The causative agent of syphilis, although not as big as in the past, is still a serious problem for mankind, is one of the four subspecies of treponema pale – Treponema pallidum. The other three subspecies cause no less unpleasant diseases – yaws, pinta, and bejel – but they occur they are today generally found only in tropical and subtropical regions.
In Europe, syphilis was particularly rampant in the 15th and 18th centuries, and according to the popular story, though unproven version, it was brought to the continent by Christopher Columbus and his crew, who returned from America in 1493.
But as an international scientific team led by Professor Verena Schünemann of the University of Zurich has recently discovered, pale treponema was common in Europe long before Columbus’ voyage.
The scientists examined the remains of four people from Finland, Estonia, and the Netherlands whose DNA test showed the presence of treponematosis. Using traditional radiocarbon analysis and molecular dating was able to establish that the genome of the bacterial pathogen belongs to just the period XV-XVIII centuries.
In addition to syphilis itself, the remains also revealed yaws, which are transmitted through simple contact with the skin. “Our data show that yaws were common in Europe in that period. Its range was not limited to the tropics as it is today,” says Verena Schünemann.
However, the discoveries did not end there. In one of the skeletons from the Netherlands, scientists found a hitherto unknown treponema lineage, which most likely evolved along with syphilis and yaws, but no longer exists as a disease today.
According to the authors of the study, this lineage is related to all modern varieties of treponema, and apparently, different subspecies were circulating in Europe in that period, which overlapped one another, affecting the same owner.
Using this discovery of theirs as the object of genetic analysis, scientists were able for the first time to date the developmental tree of pale treponema accurately. As it turned out, its current subspecies evolved over at least 2,500 years, and the last common ancestor of all strains that cause syphilis dates from the twelfth to the sixteenth century.
“Accordingly, the syphilis epidemic could hardly have been caused by Columbus’ voyage to Europe alone,” Professor Schünemann summarizes.
“The various treponematoses could have evolved together and then exchanged genetic material before or during intercontinental contacts.” Schünemann is confident that this conclusion raises new questions about the development and spread of the disease, and perhaps also about the need to reconsider existing views on syphilis and other related diseases.