If you are concerned about the possibility of contaminating a stream with your wading gear then I would suggest mixing 1 part bleach with 5 parts water and putting it into a windex bottle and spraying your boots and waders. That concentration is pretty much the standard mix. I would caution you though about spraying it on your breathable waders - I don't know if it would cause any problems.
I think more of a problem out west may come from boat trailers and birds. Backing the driftboat trailer into the water and then leaving with a bunch of mud caked to the frame probably would hold a higher potential for spreading the disease to a different drainage than waders or boots washed off with a hose. Birds eating infected fish and then defecating into another waterway also are suspected of spreading the problem. Another major threat are all the private ponds that receive hatchery fish. If these ponds receive fish that carry the disease and these fish escape through flood, emiigration, etc. then there is the potential for big problems.
Have a good night,