“Ew, you have cooties!” is more than just a childish playground taunt; cooties were (and are) a real thing, and a serious problem for much of history.
The term refers to Pediculus humanus corporis, otherwise known as the human body louse. During wartime, body lice were a scourge to soldiers and civilians in crowded conditions, and were a much more dire problem than the other human lice species (head lice and pubic lice, or “crabs”). Cooties carried typhus, a disease that killed over three million people on the former Eastern Front, between 1918 and 1922. De-lousing stations set up on both sides of the conflict kept the cootie from running rampant in Western Europe, but it was still a persistent problem throughout the war. The body louse was most notably found in German concentration camps in WWII, and the typhus carried by Pediculus humanus corporis is what killed both Anne Frank and her sister Margot.
Typhus has plagued humanity for centuries, but cooties have not. The term cootie was first coined by the British army in WWI, and is presumed to be from the Malay word kutu, meaning either biting body louse or dog tick.
Arallyn is fascinated by science and science triva. She writes a blog biomedicalephemera.tumblr.com