Fun fact, the word “cooties” didn’t originally refer to a fictitious infective agent spoken of by children; it was originally a nickname for body lice.

> Coined during World War I by British and American soldiers in the trenches of Belgium and France to describe the pervasive body lice that infested their uniforms. The word likely traces back to the Malay word kutu (parasitic louse).

Funny enough, the same sorts of activities that can “give you cooties” can in fact spread cooties (the real ones.) Though mostly due to physical proximity and skin contact.