Leviticus 13:40-44

40“If a man loses his hair and his head becomes bald, he is still ceremonially clean.

41And if he loses hair on his forehead, he simply has a bald forehead; he is still clean.

42However, if a reddish white sore appears on the bald area on top of his head or on his forehead, this is a skin disease.

43The priest must examine him, and if he finds swelling around the reddish white sore anywhere on the man’s head and it looks like a skin disease,

44the man is indeed infected with a skin disease and is unclean. The priest must pronounce him ceremonially unclean because of the sore on his head.