Key Points

• Sharp increase in the number of confirmed cases

• The majority of cases remain concentrated in the south (59%) and primarily in St. Louis, but this percentage is declining, while cases are increasing in the west (27%).

• The DENV-1 serotype remains the most common, followed by DENV-2. DENV-3 is detected only in the east.

• The proportion of hospitalized cases is higher in 2020 than in 2019.

• Numerous cases of secondary dengue have been detected, with a significant proportion in St. Louis

• All municipalities on the island are affected by viral circulation

• More than 30 imported cases in 2020 (returnees from Madagascar (DENV2), Mayotte (DENV1), the Comoros, and Tahiti).