Are you talking about the little white worms that attach to the shell of crays & other such things?? If so they are not harming anything but if you want to take them off I usually scrape them off with a finger nail or tooth brush. You could also do a 3 minute formalin bath.
My main worry is that they being wild are going to have something on them. I treat all of my fish wether they need it or not in acriflavin. Wanted to do some wild shrimp and craw's just wanted to hear from experst the best way. I've heard leeches are common and that salt would kill them like a slug.
I use to catch tons of wild crays, and just leave them in a bucket of tap water. All those white worms would die and fall off. If I just put the crawfish straight into a tank with already cycled, de-chorinated water, the worms would mutiply under the crawfish like crazy.
thats what I'm thinking. We don't have chlorine in our water. I'm going to get a livebearer be gone and see how it works. I'll do the experiment and let everyone know how it goes.