Persistent Diarrhea in Returned Travelers

Although most cases of travelers’ diarrhea are acute and self-limited, a certain percentage of travelers will develop persistent (>14 days) gastrointestinal symptoms (see Chapter 2, Travelers’ Diarrhea). The pathogenesis of persistent diarrhea in returned travelers generally falls into one of the following broad categories: 1) ongoing infection or coinfection with a second organism not targeted by initial therapy, 2) previously undiagnosed gastrointestinal disease unmasked by the enteric infection, or 3) a postinfectious phenomenon.