Leviticus 13:29

And if a man or a woman have a plague upon the head, or in the beard,

Below, regarding baldness [:40], Scripture uses the specific term “man” [Hebrew: ’ish] rather than the general term ’adam in order to exclude women. Here, Scripture is obliged to specify a man or a woman because this verse discusses the beard; and otherwise, we might interpret both on the head and in the beard to apply only to men.

IF A MAN OR WOMAN HATH AN AFFLICTION UPON THE HEAD OR THE BEARD. “Scripture intends to differentiate between a plague which is on a place where hair grows, and a plague on the flesh, for as regarding a plague on the flesh the symptom of impurity is white hair, while the symptom of a plague on a place where the hair grows is gold-colored hair — that the black hair has turned into gold-colored. 30. ‘NETHEK HU’ (IT IS A SCALL). This is the name of the plague on a place where hair grows.” This is Rashi’s language.
It would appear from this language that the difference between a plague upon the head or beard and a plague in the skin of the flesh, is that which Rashi mentioned, namely, the white hair and the gold-colored; thus if a plague occurs in any of its four colors (bright-white like snow), se’eith (white as white wool); sid ha’heichal (the white lime used in the Sanctuary), and krum beitza (the membrane of an egg). Of these four shades the whitest is bahereth, the next is se’eith, the next sid, and the dullest is krum beitza (Rambam Mishneh Torah, Hilchoth Tum’ath Tzara’ath 1:2). See further Note 107. in a place where hair grows upon the head or beard, and if the hair became gold-colored, then the person is impure, just as he is impure if the hair turned white in a plague on the skin of the flesh. But how is it possible to say so! Rashi himself has written [further on]: “As the leprosy appeareth in the skin of the flesh. [It is like the color of the leprosy which is mentioned in the section dealing with plagues of the skin of the flesh, namely] that it makes one impure by means of any of the four white colors, (bright-white like snow), se’eith (white as white wool); sid ha’heichal (the white lime used in the Sanctuary), and krum beitza (the membrane of an egg). Of these four shades the whitest is bahereth, the next is se’eith, the next sid, and the dullest is krum beitza (Rambam Mishneh Torah, Hilchoth Tum’ath Tzara’ath 1:2). See further Note 107. and it is not to be treated like the color of the nethakim (scalls) on the place where hair grows, which do not render a person impure by reason of the four colors: the se’eith and its secondary shade, and bahereth and its secondary shade!” is the secondary shade of bahereth, and krum beitza is the subsidiary species of se’eith. A priest who …