Local Diseases

[bobbin]

It wouldn't really work like that, if there was a plant that was toxic enough to kill someone, the locals would just not eat it in the first place.

It would be pretty stupid of them to bilndly continue eating something lethal for generations until someone developed resistance.

As for parasites, they are different because your body's immune system doesn't work on that scale, it's the reason nobody is resistant to things like tapeworms or headlice.