Hi Steve @SteveBaker,
I agree completely with your physician (I am a medical researcher).
What I do to really clean my harps is to disassemble them (remove the covers and unscrew the reed plates from the comb), and put all parts that are not wood (covers, reed plates and plastic or metal combs) into an ultrasonic jewelry cleaner (use the search term “ultrasonic jewelry cleaner” at amazon) with sufficient warm water to cover the parts and several drops of dish washing detergent, then let it do its thing for about 3-4 minutes. Rinse with fresh warm water and let everything dry. Works into the tightest spaces around the reed rivet ends and never fails to satisfy my needs for a clean harp.
I clean wood combs with a soft tooth brush and a light coating of lysol spray. Then I wipe it clean (do not let the wood get soaked) and dry it completely.