Everything you never wanted to know about the mites that eat, crawl, and have sex on your face : Not Exactly Rocket Science

"But it’s hard to say exactly how common they are. The first estimate came from a 1903 study, which found the critters in 49 out of 100 French cadavers. The next count, from 1908, found them in 97 out of 100 German cadavers."

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