Key Points

• Difficulties accessing water and sanitation in Mayotte, making the territory vulnerable to these three diseases: hepatitis A, typhoid fever, and diphtheria.

• The incidence of diphtheria has been rising in recent years in Mayotte: 17 cases between January 1, 2022, and August 31, 2024 (compared to 14 cases between January 2019 and December 2021 and 0 to 2 cases per year prior to 2019). The two main clusters of cases were: Handréma (n=5) and Ongojou (n=3) in 2022. A 10-year-old child was admitted to the intensive care unit, and a child under 1 year of age died.

• A significant incidence of typhoid fever in Mayotte, with a reported rate approximately 70 times higher than the incidence rate in mainland France. 186 cases were reported in Mayotte between January 1, 2022, and August 31, 2024. The year 2022 alone accounted for 123 cases, and 15 cases were reported in 2023, representing significant fluctuations in the incidence of the disease in the territory.

• A stable reporting rate for hepatitis A in Mayotte, with between 20 and 29 cases reported between January 1, 2022, and August 31, 2024, with no clusters of cases identified. A hospitalization rate of 41% was observed, but these were short hospital stays without admission to intensive care. No deaths were reported during this period.

• Exposure to the three pathogens under consideration was identified during patient investigations, particularly in connection with the use of river water, but also in connection with the consumption of food purchased from informal vendors (fish, various vegetables, etc.).