Prehistoric faeces reveals roundworm infection

In the third and fourth centuries BCE, the Ancient Greek medical practitioner Hippocrates, together with his students, compiled a vast collection of texts, known collectively as the Hippocratic Corpus.

The masterwork includes Hippocrates’ theory that illness was caused by an imbalance of bodily “humours” – an idea that was to dominate medical thought for 2000 years. However, it also contains clinical descriptions of many diseases and parasites.

Prime among the latter are three species of intestinal worm, which the writer called Helmins strongyle, Ascaris, and Helmins plateia. The names did not survive in common usage into the modern era, so for centuries medical authorities, biologists and historians have been trying to determine exactly what they were.

Now, however, at least two-thirds of the mystery appears to have been solved by a team led by Evilena Anastasiou from the UK’s University of Cambridge. Publishing in the Journal of Archaeological Science, the team reveals the identity of two of the mystery parasites with a high degree of certainty.

The researchers are confident of their conclusions, because the way they conducted their investigation leaves little room for doubt. They dug down into 6000-year-old graves and started sifting through some prehistoric poo.

Anastasiou and her colleagues conducted excavations on the Greek island of Kea, not far from Kos, where Hippocrates lived.

They selected a total of 25 burial states that dated variously from the Neolithic period in the fourth millennium BCE, the Bronze Age (second millennium BCE) and the Roman period, which stretched from 146 BCE to 330 CE).

Having reached the bones contained in the graves, the scientists then began carefully sifting through the soil that gathered around the pelvic bones of the deceased – soil that was in significant part derived from faeces.

Their research bore fruit – or rather, worm eggs. The Neolithic graves yielded ancient eggs from the whipworm (Trichuris trichiura), and the more recent Bronze Age sites contained eggs from roundworm (Ascaris lumbricoides).

The latter, says co-author Piers Mitchell is very likely to have been what the Hippocratic Corpus refers to as Helmins strongyle.

“The Ascaris worm described in the ancient medical texts may well have referred to two parasites, pinworm and whipworm, with the latter being found at Kea,” he adds. 

“Until now we only had estimates from historians as to what kinds of parasites were described in the ancient Greek medical texts. Our research confirms some aspects of what the historians thought, but also adds new information that the historians did not expect, such as that whipworm was present.”

“Finding the eggs of intestinal parasites as early as the Neolithic period in Greece is a key advance in our field,” adds Anastasiou. “This provides the earliest evidence for parasitic worms in ancient Greece.”