Ancient Toilets Reveal Earliest Evidence of Dysentery Parasite

The giardia parasite has plagued humans for centuries, causing dysentery which can result in diarrhea, cramps and fever. Researchers have now discovered evidence of giardia in the remains of two 2,600-year-old toilets located in Jerusalem used by wealthy inhabitants. The discovery is the oldest biological evidence of the parasite found anywhere in the world, according to a report by Parasitology. Giardia duodenalis is a single-cell parasite that can be found in human intestines worldwide and while some intestinal parasites can survive and be preserved in the ground for centuries, giardia rapidly disintegrates and cannot be seen under a microscope.

Archaeologists working in Jerusalem in 1991 and 2019 at two different excavations uncovered stone toilet seats within the foundations of large mansion-like homes. Soil samples taken from beneath the toilet seats showed traces of possible intestinal parasites including roundworm. Researchers took the analysis further, using antibodies to look for the remains of giardia, as well as two other fragile parasites, in the decomposed feces under the toilet seats. Discovering giardia in the region at that time was thought to be unlikely, given the difficulty in reconstructing the movement of ancient disease, according to Piers Mitchel, a paleoparasitologist at the University of Cambridge. However, the discovery hints that the parasite was a common occurrence in the region, according to Mattieu le Bailly from the University Bourgogne Franche-Comté in Besançon, France who was not involved in the study.

Mitchel added that it makes sense for giardia to have existed in ancient Jerusalem, given the hot, dry climate in the Iron Age city which was plagued by insects and contaminated water, the two primary ways in which the parasite spreads. As a non-profit news organization, it is our mission to provide the public with accurate and engaging scientific news. Donations from our readers allow us to provide free access to our content and support science journalism.