Warning: This list includes NSFW content.

Today's science lesson: Botflies reproduce by laying eggs on a host, or on other insects, like mosquitoes. When a mosquito then finds its own next victim, the body heat causes these eggs to hatch, and the botfly larvae burrow under the skin of the new host. A larva will feed on the host as it grows, before bursting from the body to complete its pupal stage in the soil. And some species of botfly regularly choose a human body for a starter home.

If this fact of life isn't gross enough, maybe you'd like to watch a botfly as it's extracted from a woman's scalp. Or maybe a few glimpses of massive cysts or oozing abscesses are more up your alley.

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Here, harvested from YouTube like a field of rotten crops, are some of the vilest, most vomit-inducing videos available, to remind you that, hey, your day really wasn't all that bad.

Note: Most of these videos are NSFW, due to language and explicit content.

What's the most disgusting video you've ever seen on YouTube? Share in the comments section below.

Thumbnail image courtesy of iStockphoto, timsa