An outbreak of gastroenteritis has affected the commune of Rousset in the Bouches-du-Rhône department of southeastern France, with more than 750 people reporting symptoms since mid-April 2026.
According to regional health authorities, the outbreak began on April 13, 2026, and peaked the following day. By April 23, over 1,000 residents had completed an online epidemiological questionnaire distributed by the Agence régionale de Santé (ARS) Provence-Alpes-Côte d’Azur and Santé publique France Paca-Corse. Of those respondents, more than 750 reported experiencing diarrhea and/or vomiting, which accounted for approximately 90 percent of symptomatic cases.
Health officials noted that 85 percent of those who reported illness were either residents of Rousset or had recently visited the commune. While 25 individuals required short-term hospitalization, no severe or fatal cases have been identified to date.
The suspected source of contamination is the municipal drinking water supply. In response, local authorities initiated a bottled water distribution campaign starting in early April, prioritizing schools, daycare centers, and nursing homes before expanding to the general population. The mayor of Rousset, Philippe Pignon, activated the Communal Safeguard Plan, and environmental investigations into the water network remain ongoing.
Although recent water analyses have shown compliance with safety standards, health agencies continue to monitor water quality closely and advise residents to practice heightened hygiene measures, including frequent handwashing.
The outbreak appears to be subsiding, with a sharp decline in new cases observed after the April 14 peak. The ARS has kept the epidemiological survey open through April 26, 2026, to gather final data on the incident’s scope and transmission patterns.
