Key Points

• In week 37, there was a decline in emergency department visits for gastroenteritis following four consecutive weeks of increases, with an activity rate significantly higher than those observed in the previous three years; the outbreak is still ongoing;

• Rotavirus, Escherichia coli, and Shigella sp., identified in the majority of biological samples analyzed, are the pathogens currently circulating and constitute the leading cause of acute viral gastroenteritis in children under 5 years of age during the winter season;

• Sales of anti-diarrheal medications and oral rehydration solutions (ORS) in pharmacies are higher than the average for previous years;

• To date, there has been no resurgence of waterborne diseases directly linked to the current water shortage;

• The water shortage in Mayotte may lead to a decline in vigilance regarding the implementation of basic hygiene measures, which could trigger outbreaks of waterborne diseases such as typhoid fever and hepatitis A—which are endemic in the region—or affect the intensity or duration of the current gastroenteritis epidemic.