I have long time been convinced that there is no 100% option not to become infected with parasites. Even being the most sterile, there is a risk of getting this infection. Here you need to think about how to get rid of it. Personally, I have only had one case involving parasites. My cat had parasites a few years ago and immediately became noticeably less active. The drug that really worked for her is called niclosamide. If you don't know what is it, you can check out here
niclosam.com. It suits perfectly against parasites. I added this powder mixture to the cat's food, and began to notice that every day she was getting better and better, she ate more and ran more actively. She fully recovered after about a week, but sometimes the course may take longer.