Leprosy: Garments: Incurable Infected With, Burned

On the seventh day the priest shall reexamine it, and if the mildew has spread in the fabric, weave, knit, or leather, then regardless of how it is used, it is a harmful mildew; the article is unclean.

He is to burn the fabric, weave, or knit, whether the contaminated item is wool or linen or leather. Since the mildew is harmful, the article must be burned up.