In the Discworld books witches are much like local doctors. There’s a young witch that can’t convince a family to move the privy away from the garden, which is making them sick. She tries to explain there are tiny, tiny animals that are coming from the poop and that’s what’s making them ill. They smile politely and don’t change anything.

The old witch comes along and it explains that the problem is the goblins in the outhouse and to move it far away from the garden. They happily do so.

This episode of This Podcast Will Kill You actually goes into that: https://player.fm/series/series-2359894/ep-31-giardia-gerardia

There is also a transcript if you just want to read about it: https://thispodcastwillkillyou.com/wp-content/uploads/2021/07/TPWKY-Episode-31-Giardia.pdf

(Warning: they make an alcoholic beverage towards the beginning of each episode in case anyone is in recovery)

There’s a part of Old Yeller dedicated to this. His uncle doesn’t believe in germs because germs aren’t in the Bible.

Reminds me of this work by Latour. It goes into the tremendous amount of oftentimes political labor that goes into the establishment of new scientific knowledge as paradigmatic:

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

Horton Hears a Who if Horton was the one saying “Boil that dust speck! Boil that dust speck!”

Wee beasties!