How to completely get rid of bug infestations in RimWorld?

Solution 1:

These mods disable / weaken bugs to the point of being essentially a non-threat, so even if they show up, they won't be an issue:

ez infestation

This mod makes those damn bugs weak and minimizes the number of bug spawn. your colonist can easily beat those bugs even with bare hands with this mod.
No Infestation

Remove infestation event from your game. (in case you always forgot about turning it off in the scenario editor)