TT #249 · Parshas Tazria · Aliyah 7 · Passuk 46
English: All the days that the affliction is upon him he shall be impure; he is impure. He shall dwell alone; his dwelling shall be outside the camp.
Torah Temimah cites Sifra (Toras Kohanim) for limiting the impure period to the days during which the lesion remains present.
Sifra — Vayikra 13, Midrash Sefer
English: “The days during which the affliction is in him” excludes days after the baheret has been cut off.
Textual derivation
The phrase “the days during which the affliction is in him” limits the ordinary impurity period to the time the lesion is present; days after its removal are not counted in that phrase.