Tapeworm infection is caused by ingesting food or water contaminated with tapeworm eggs or larvae. If you ingest certain tapeworm eggs, they can migrate outside your intestines and form larval cysts in body tissues and organs (invasive infection). If you ingest tapeworm larvae, however, they develop into adult tapeworms in your intestines.
Most human infections caused by D. pacificum and, allegedly, D. latum have been reported from Chile and Peru, with other cases in Argentina, Brazil, and Ecuador, including recent outbreaks of diphyllobothriosis in Rio de Janeiro and São Paulo. Adult tapeworm infections are treated with anthelmintic medication which is kills parasitic worms and makes the worms pass out of your intestine in your stools.