Epidemiology of Escherichia coli in the United States.

Current evidence suggests that diarrheagenic E. coli are not important causes of disease in the sanitized urban centers of the United States at this time. However, enterotoxigenic E. coli are a leading cause of diarrhea among travelers who visit developing countries. The failure of diarrheagenic E. coli pathogens to gain a foothold in this country, despite problems with enteropathogenic E. coli in nurseries during the 1940s and 1950s and the more recent multiple introductions of enterotoxigenic E. coli by travelers returning from developing areas of the world, demonstrates the epidemiologic impotence of diarrheagenic E. coli in the relatively sanitized environment of the United States. Nondiarrheagenic E. coli seem to be major pathogens in community-acquired and nosocomial infections in extraintestinal sites.