H

aemophilus ducreyi. This organism can be summed up by one word: Chancroid. When you hear that word, you should envision a painful ulcer on someones genitalia. H. ducreyi is a sexually transmitted disease (STD), and it's the #1 cause of genital ulceration in the world. Dubious distinction, eh?

If you have an ulceration on your private parts and suspect it's bacterial in origin, there is an easy way for you to figure out whether or not you have contracted H. ducreyi or syphilis. Poke it. If it hurts, it's H. ducreyi. If it doesn't hurt, it's syphilis.

Fortunately for everyone involved here, I won't be showing any pictures of genital ulcers. Of course, it'll be interesting to see how many people Google brings here due to the search for the words "genital" and "ulcer".