H2O2 is very effective at eliminating the small parasites and detoxifying the body, making it a less habitable place for the larger ones. I do not know if it directly kills the larger parasites like flukes and worms, but it is very effective in eliminating candida, bacteria, viruses and the like. You can find more info from the ozonated oil link in my profile. Go to the articles page and you will find a lot of info on H2O2. The useful links page will also send you to many more sources of information.
hope this helps,
paul