sciencehabit writes: More than 6000 years ago, a small child in ancient Mesopotamia went wading in a nearby stream. He or she might have been bathing, playing, or merely cleaning up after answering nature’s call on the stream’s bank, a common practice in the days long before toilets. But the wader was out of luck; lurking in the water were the treacherous larvae of a parasite called Schistosoma. It is hard to say which symptoms the ancient Mesopotamian child suffered because no soft tissue remains on his or her skeleton today. The disease did leave a trace, however. The mature worms in the child’s pelvis laid eggs, and one of them stayed buried for thousands of years. Now, a team of researchers has unearthed the egg in a grave in the Tell Zeidan archaeological site in modern Syria. Before the Tell Zeidan discovery, the oldest confirmed case of schistosomiasis was a 5200-year-old mummy in Egypt. The egg at Tell Zeidan is the first confirmation that the infection existed in Mesopotamia as well.