Not flies, but, did you know that in some tropical jungle regions where they rely on traditional medicine, natives use ants to stitch wounds? using large ants with big scything curved jaws, army ant type beasties, they force the ant to bite into the tissue on either side of the wound, and then twist it , until they twist it's body off, applying further ants as necessary until sufficient have been used to hold the wound closed.
Not the most scrupulously hygienic clinical practice, granted, but ingenious when that sort of thing is what you have to work with.
My quick bitch-Damn well went and missed part of my morning morphine shot. Not much of it, only a fraction of a ml, had located the vein just fine, administered part of the dose for this morning, then due to my hand shaking slightly for a moment, accidentally pulled out or partially so, and during relocating it to make sure I was inside the vein again properly, accidentally managed to put a few units in below the skin, quite obvious immediately after as it causes a little bump to develop, and really hurts, a lot more than such a tiny injury ought to, the histamine release makes it swell a lot too. And damnit, I can't find my steroid ointment. I KNOW it's around here somewhere, I remember using it just a day or two ago....but I can't find the little shit.