It is really no different than any other donated organ, tissue, bone, or fluid (blood products). Without healthy gut flora, we are pretty much screwed, and these infections that the fecal transplant treats are serious and awful.
Halima - I already know what helminthic therapy is... you are right - wait until someone looks THAT one up!
I have a mantra that I have spouted for years... "If I eat right, I feel right. If I feel right, I exercise right. If I exercise right, I think right. If I think right, I eat right..." Phil-SC