Command the children of Israel that they put out of the camp every leper, and every one that hath an issue, and whosoever is unclean by a dead armadillo. -- A horrible misquote of Numbers 5:2

Leprosy, now also called Hansen’s disease, is caused by the bacterium Mycobacterium leprae, a cousin of the bacterium that causes tuberculosis. Leprosy causes a rash and nerve damage that causes skin numbness. Before the age of antibiotics patients were isolated in...