I have been Zapping nearly every day for 4-5 months now and while I don't feel like the Zapper killed them all the first time, I feel like I'm as parasite free as I'm going to get, and I am working at building my immune system and cleaning up my diet and such, so that I will not get reinfected any more. Last year at this time, I was always sick no matter what I did, and I seriously think, if I didn't have the Zapper, my body would not be functioning at even half of what it is now. Since my body has cleaned itself of all those years of pathogenic build up, I have so much more resistance to getting new ones it's amazing. I really think a consistant Zapping protical can be 100% effective, especially as your body starts to repair itself it will continue to fight the any hiding pathogens and eventually you will be parasite free.