The present invention is directed toward a wound dressing comprising a foam body made of polyvinyl acetal material treated with a plurality of colored biocidal dyes with at least one of the dyes being gram positive and at least one of the dyes being gram negative to dye the body a distinct color. The body has at least one planar surface and ranges from about 1 mm to about 3 mm in thickness and has an outer adhesive section secured to the body. The body when placed in contact with an infected wound site changing color.
