Key Points

Acute Gastroenteritis (AGE)

• Seasonal AGE outbreak caused by Rotavirus: indicators (activity and positivity rate) are declining and below the epidemic threshold

Influenza

• Transition to the pre-epidemic phase in S44

Mosquito-borne diseases

• Chikungunya: following the end of the southern winter epidemic with 1,259 confirmed cases, low-level circulation of the virus and risk of a resurgence during the rainy season

• Dengue: Low dengue circulation in 2025 in Mayotte, marked by a peak in May followed by no cases since June

• Malaria: 101 cases of malaria have been detected in Mayotte since January 1, 2025, including 16 locally acquired cases, mainly located in Bandrélé

Waterborne diseases

• Hepatitis A: Resurgence of hepatitis A cases in 2025, marked by two distinct epidemic waves: a first wave following Cyclone Chido and a second wave beginning in July 2025

• Typhoid fever: Resurgence of typhoid fever cases in 2025, with a peak observed in February, in the wake of Cyclone Chido, and cases recorded throughout the year