A method for treating a sulfur-containing fabric and sulfur-containing fabrics with excellent antimicrobial properties are disclosed. First an aluminum salt is added to a sulfur-containing fabric. That product is then rinsed. The rinsed product is combined with an antimicrobial. In one embodiment, the sulfur-containing fabric is combined with an aqueous solution of an oxidizing agent prior to the addition of the aluminum salt. Fabrics treated by the method retain excellent antimicrobial activity even after repeated washings.