How ancient people kill fleas?

[cheetaman]

The "fleas" caused    a lot if troubles in history.

[Sensei]

In Roman Empire rich people were funding and building public baths.

https://en.wikipedia.org/wiki/Ancient_Roman_bathing

 

ps. It's better to prevent, in smart way, than having to fight with something when it appears (mostly because of stupidity/incompetence to see in advance).