Bob - where do you see dusts that are DE? TSC and Amazon both lead with a permethrin dusts.This is correct. Most "dusts" are DE. If you have a dust with premethrin in it then that might be effective but I'm not down with DE as a killer of parasites. I don't agree with the "science".
This is the TSC one for example:
https://www.tractorsupply.com/tsc/p...v5o7SunsKslT7IFQF2jHZXTv0hZOwFKRoCA_oQAvD_BwE