Zhang Xiaoying nodded, "Yes, because dead objects are more likely to nurture the bugs that can make people sick. When the flood came, so many livestock were drowned, their bodies sat in the water, and the water became unclean. Drinking such raw water easily led to the plague."
"In other words, the plague is actually caused by those invisible bugs carrying disease within our bodies, but since we cannot see these bugs, we can only diagnose and treat the illness based on the symptoms that manifest. There is always a natural enemy to every creature; certainly, there exists a medicine that is deadly to them."
The concept of a virus was too complex and beyond their understanding, so Zhang Xiaoying did not want to explain it in such complicated terms, and instead used simpler language they could understand.
She also tried to keep them from thinking in the direction of feudal superstition.