The species " Trichinella spiralis ", commonly known as the'trichina worm', occurs in rats, pigs, and humans, and is responsible for the disease trichinosis . " Baylisascaris " usually infests wild animals, but can be deadly to humans, as well . " Dirofilaria immitis " are known for causing heartworm disease by inhabiting the hearts, arteries, and lungs of dogs and some cats . " Haemonchus contortus " is one of the most abundant infectious agents in sheep around the world, causing great economic damage to sheep.
