The present invention is directed toward a wound dressing comprising a foam body made of polyurethane 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 10 mm in thickness and has an outer film cover and border with a hydrogel adhesive secured to the body. The foam body changes color when placed in contact with an infected wound site.
