A medical device comprising a device that covers at least a portion of a patient's skin and has an inner surface designed to be in contact with the patient's skin. It contains a multi-ply knit fabric that contains a first knit ply and a second knit ply. The first knit ply contains a plurality of first yarns and forms the upper surface of the fabric. The second knit ply contains a plurality of polytetrafluoroethylene (PTFE) yarns which forms the lower surface of the fabric. The first and second ply are integrated through combined portions formed by interlacing first yarns among the PTFE yarns, interlacing PTFE yarns among the first yarns, and interlacing a plurality of third yarns among the first and the PTFE yarns. The multi-ply knit fabric also contains a composition comprising at least one silver ion-containing compound on at least the upper surface of the multi-ply knit fabric.