Alumna Profile

Kristin Harper ’02

Hunting the spirochete: Kristin Harper thinks Christopher Columbus may be the culprit after all.

Skeletons and Syphilis

By Chris Lydgate ’90

The origin of syphilis is one of history’s great puzzles. The pox first appeared in 1495, when it raged through the army of Charles VIII of France as he retreated from Naples. The French called it the Italian disease, the Italians, the French disease. But what was the source of the outbreak? Historians have long wondered if syphilis was imported from the New World by Columbus, a sort of cosmic payback for measles and smallpox.

The Columbian hypothesis has come under fire recently, however, with reports of Old World skeletons buried before 1493 bearing marks of syphilitic infection. Poxy scars were found on the bones of four English monks from Hull buried before Columbus ever set sail, for example—a fatal blow to the theory.

Or, so it seemed. In December, however, Kristin Harper and colleagues from Emory published a paper taking a closer look at the skeletal evidence. Radiocarbon dating, it turns out, depends on the quantity of fish in the diet of the skeleton’s erstwhile inhabitant; moreover, spotting syphilis in bones is a tricky game.

After setting up rigorous criteria both for diagnosing syphilis and for dating the bones, Kristin’s team reviewed 54 reports and could not find a single Old World skeleton that was both clearly pre-Columbian and clearly syphilitic. The English monks? Pox-ridden sinners, to be sure. But once Kristin adjusted the radiocarbon dates for their fishy diet, it looks like the monks could have died long after Columbus.

This research builds on a pioneering 2008 paper in which Kristin used genetic analysis to build a family tree of syphilis and related treponemal infections. That analysis showed that syphilis is genetically most similar to a disease called yaws found in remote areas of Guyana, lending further weight to the hypothesis that syphilis originated in the New World.