My guess is that the epidemic was sexual or associated with what adults ate, as opposed to what children and the elderly ate...
The remains of 97 human bodies have been found stuffed into a small 5,000-year-old house in a prehistoric village in northeast China, researchers report in two separate studies.
The bodies of juveniles, young adults and middle-age adults were packed together in the house -- smaller than a modern-day squash court -- before it burnt down. Anthropologists who studied the remains say a "prehistoric disaster," possibly an epidemic of some sort, killed these people.
The site, whose modern-day name is "Hamin Mangha," dates back to a time before writing was used in the area, when people lived in relatively small settlements, growing crops and hunting for food. The village contains the remains of pottery, grinding instruments, arrows and spearheads, providing information on their way of life. [In Photos: Remains of 'End of World' Epidemic Found in Ancient Egypt]
"Hamin Mangha site is the largest and best-preserved prehistoric settlement site found to date in northeast China," a team of archaeologists wrote in a translated report published in the most recent edition of the journal Chinese Archaeology (the original report appeared in Chinese in the journal Kaogu). In one field season, between April and November 2011, the researchers found the foundations of 29 houses, most of which are simple one-room structures containing a hearth and doorway.