Introduction. In June 2005, several cases of gastroenteritis were reported among the 64 participants in two consecutive trips to Egypt (June 2–10 and June 10–17, 2005) organized by a works council. The tourists were all staying on a full-board basis at an international hotel in the Hurghada region. A descriptive investigation was conducted to confirm and describe this outbreak and to propose appropriate control and prevention measures. Methods. A retrospective cohort study was conducted by telephone using a comprehensive list of the 64 participants. A case was defined as any person who participated in one of the two trips to Egypt and reported having diarrhea (at least three loose stools per day) or vomiting. The questionnaire focused primarily on the clinical signs observed and their medical management. A dietary survey was not possible due to the inability to obtain the menus provided by the hotel. Stool cultures were performed on some of the patients. An inspection of the hotel, focusing on food preparation and general hygiene conditions, was conducted by officials from the hotel chain as well as by the Egyptian Ministry of Health and the Ministry of Tourism. Results. Forty-six of the 56 participants surveyed (82%) became ill during their stay or up to two days after returning to France. Stool culture analyses revealed multiple contamination with Salmonella sp., Shigella sonnei, and Hafnia alvei. One case of Hepatitis A emerged 40 days after returning to France. No common source of contamination could be identified by the cohort investigation. An inspection of the hotel suggested deficiencies in general hygiene conditions, particularly contact between cooks and gardeners exposed to the establishment’s wastewater used for watering plants. Conclusions. The investigation confirmed the existence of an outbreak of mixed-germ gastroenteritis among participants in the two trips to Egypt, linked to poor general hygiene conditions. Disinfection of the hotel premises was carried out, and hygiene practices were reviewed. Participants were informed of measures to prevent secondary transmission (handwashing, etc.). (R.A)