Ultraviolet light apparently healed an infection for me.
I got a painful infection in one finger a few weeks ago when I knicked myself while helping skin a mountain lion. Tried the usual alcohol, hydrogen peroxide, opening skin to get meds down into the wound, polysporin, etc. with a band-aid to hold the med in place. It would fade a bit then come back stronger and more painful.
I tried ultraviolet light from a cheap disinfecting wand, ten seconds of light exposure with the light half an inch from the injury. Did that once a day for two days and the infection was totally gone and has not returned.
UV may cause skin cancer but that is extremely unlikely from a brief exposure. From reading online apparently UV is cautiously being used more and more for such healing.
FWIW
