This is Scientific American 60 Second Science.

I'm Cynthia Graber.

Got a minute?

For thousands of years, what's called the Silk Road was a group of land and sea trade routes

that connected the far east with South Asia, Africa, the Middle East, and southern Europe.

Of course, when humans travel, they carried their pathogens with them.

So scientists and historians have wondered if the Silk Road was a transmission route not just for goods but for infectious disease.

Now we have the first hard evidence of ancient Silk Road travelers spreading their infections.

The find comes from a 2,000 year old latrine that had first been

excavated in 1992. The report is in the Journal of Archaeological Science.

So the site is a relay station on the Silk Road in northwest China.

It's just to the eastern end of the Tamarin Basin, which is a large arid area

that's just to the east of the Taclamakan desert,

and not far from the Gobi Desert.

So this is a dry part of China.

Piers Mitchell, Paleopathologist at the University of Cambridge and one of the studies authors,

along with his student Ivy Yea and colleagues in China.

In the latrine, archaeologists found used hygiene sticks wrapped with cloth.

These were used for what you think they were used for.

This excavation was great because the cloth was still preserved and the

feces was still adherent to the cloth on some of the sticks. And so the

archaeologists kept these sticks in the museum and so my PhD student IVA who's first author on the paper she went

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