2,000 years ago the Silk Road opened up the first long-distance trade of goods between East Asia and the Middle East and Mediterranean; and with it, languages, philosophies, cultural practices and technologies also crossed the globe. And these tradesmen and explorers also brought with them other gifts along their routes, including infectious diseases–the first evidence of which has just been uncovered through examination of ancient poop.
The stomach churning discovery was conducted by researchers from University of Cambridge’s Department of Archaeology and Anthropology who extracted ‘personal hygiene sticks’ from a latrine that sat on one of the Silk Road’s largest relay routes, on eastern margins of the Tamrin Basin and was in use from around 111 BC to 109 AD.
Personal hygiene sticks were used for wiping excrement from ones rear, and as such, these ancient sticks carry the well-preserved bathroom remains of early travelers. So while it’s long been believed that the Silk Road was an early conduit for infectious disease, researchers were able to take the ancient crap and study it with microscopy to determine exactly what bugs were hitching a ride.
Under close examination the feces were found to include eggs from four species of parasitic worm: roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura), tapeworm (Taenia sp.), and Chinese liver fluke (Clonorchis sinensis). Which raises some questions about the health the ancient tradesmen and government officials.
That aside, it is the Chinese liver fluke eggs that proved most exciting for the researchers. As Hui-Yuan Yeh, one of the study’s authors, said in a statement:
When I first saw the Chinese liver fluke egg down the microscope I knew that we had made a momentous discovery
And that’s because Chinese liver fluke–which causes abdominal pain, diarrhoea, jaundice and liver cancer, in case you were wondering–can only complete it’s life cycle in damp marshy environments. The arid Taklamakan Desert, where the Tamrin Basin latrine lies, isn’t hospitable to this particular flatworm. Indeed, the nearest endemic area for the Chinese liver fluke worm is in Dunhuang, which is around 1,500km away.
So there we have it; the intrepid, ancient, and in at least on case, rather sickly, travelers of the Silk Road were transporting infectious disease. Hui-Yuan Yeh continues:
Our study is the first to use archaeological evidence from a site on the Silk Road to demonstrate that travelers were taking infectious diseases with them over these huge distances.
Taklamakan Desert photo CC SA by 3.0 taylorandayumi on Flickr