They especially kill the types of parasites that are common in places papayas naturally grow-- but are also effective against any types.
The Papaya- though sweet, also has good digestive enzymes that help the intestinal tract against parasites. The entire Papaya seems designed by God to help man against parasites that Satan unleashed in the World.
Also raw pineapple too. I also read raw coconut is good against parasites!
Nevertheless, people throw away Watermelon seeds and Papaya seeds but they are both very valuable against parasites, so I'd save them and eat them!!