Some time ago, a reader wrote to us about worms in humans in Africa. The worms were “embedding in humans” and then they would work their way out through the afflicted person’s legs – a painful experience, not surprisingly. The reader said he came across this rather horrifying human worm parasite in an article published in Smithsonian Magazine in 2011, and it seemed as though he wanted us to find out the issue of the magazine in which this article was printed. Despite a few searches, we didn’t find any specific article (at least not in 2011), but we suspect the article might have been about guinea worm disease (GMD), or dracunculiasis. Guinea worm disease is in fact caused by a worm – the Dracunculus parasite, which goes by the scientific name Dracunculus medinensis – and it does afflict humans (along with a few other animals). What are guinea worms and guinea worm disease?