In the Old Testament, there is a connection between gossip (Hebrew: lashon hara) and leprosy (tzara’at–probably not what we know as leprosy or Hanson’s disease, but rather a very contagious skin disease). In Numbers 12, Miriam speaks against Moses (lashon hara) and is struck with tzara’at, a serious skin disease. For this, she was banished outside the camp for seven days.
Old Testament rules required isolation of anyone with tzara’at. If anyone came near, the leper had to call out, “Unclean! Unclean!”