Shiga toxin-producing Escherichia coli (STEC) were recognized as human pathogens in the United States in 1982, following two outbreaks of bloody diarrhea linked to the consumption of hamburgers contaminated with Escherichia coli O157:H7. STEC infections can present as mild, non-bloody diarrhea, but hemorrhagic colitis is the most common form. The median incubation period is 3 days (ranging from 1 to 8 days). The course is most often spontaneously favorable within a week. However, hemolytic uremic syndrome (HUS) is a serious complication that is more common at the extremes of life. The proportion of Escherichia coli O157 infections that progress to HUS, regardless of the patient’s age, ranges from 3% to 9% in sporadic case series and up to 20% in certain outbreaks. Serotype 0157:H7 is the most commonly encountered in STEC infections, but other serogroups may be involved (026, 0103, 0111, etc.). Cattle are the primary reservoir of STEC, but this bacterium has also been isolated from other animals (deer, sheep, goats, horses, dogs, birds, flies) and persists in the environment (water, manure, soil). Numerous outbreaks have been reported in several industrialized countries, including some large-scale outbreaks with high fatality rates, such as those in Scotland and Japan. Many food vehicles for STEC have been implicated during these outbreaks. The most common sources are bovine: beef, particularly ground beef, and unpasteurized milk; however, other sources have also been implicated, such as fermented meat, apple juice, raw vegetables, or drinking water. Human-to-human transmission within families or communities has also been observed, as well as transmission through direct contact with infected animals or their feces. In France, in the absence of routine STEC testing by medical and biological laboratories, surveillance of STEC infections is based on the surveillance of pediatric HUS. Established in 1996, this surveillance relies on a network of 30 pediatric nephrology departments in hospitals spread across the entire metropolitan territory. The main objectives of this surveillance are to track the spatial and temporal trends of HUS in children under 2 15 years of age in France and to detect epidemic outbreaks. Thus, since 1996, the majority of pediatric HUS cases have been sporadic (with no identified link to another case) and associated with STEC infection, with a high prevalence of serogroup O157. Furthermore, surveillance of clusters of STEC infections is also conducted through the mandatory reporting of collective foodborne illnesses (TIAC) to departmental health authorities (Decree No. 86-770 of June 10, 1986).