There are some clues. In the human excrement found intact in
another burial site, scientists found egg remains of the
trematode species Fasciola buski. Today, this parasitic
flatworm is endemic to certain areas of Thailand and is most
common where aquatic plants are cultivated, particularly the
water caltrop. The University of Otago's Dave Morseth, a
parasitologist, reports that infestation of this parasite
would greatly reduce human vitality. Anemia associated with
malaria may also have affected the people greatly.