Stop right there. Don't go any further. Some things can't be unseen. You're brain isn't a hard drive from which you can permanently erase images. These images will sear into your neocortex, much to your eyeballs' dismay. Scroll down to find out why. But if you don't want to know why and you want to see previous posts, close your eyes and give your mouse wheel a few rotations, or press that Page Down button a few times. You'll be safe.
If you want to read on, you proceed at your own risk.
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Behold the parasite known as the African Eye Worm. Yes, that's a parasitic worm in that poor soul's eyeball.
Read this Wikipedia article (link above) for all the gory details, but suffice it to say that the vectors for this parasite include bites from the horse, deer, and mango flies, and that you don't want this infection.