And if you think about it, most people don't throughly cook their meat before eating, especially steak, and certainly not sushi. Also pork has to be heated at a certain temperature to kill parasites, and not just simply be completely cooked.
As you can see, the sources of the meat themselves are the underlying cause of parasites, which explains why America has a parasite infestation that encompasses 85-95% of the population.
Asian people regularly "de-worm" themselves once a year. We should similarly follow this route.
Flukes are surviving because they have a comprehensive adaptive system in our current environment. We should also include tap water to our list of woes.