Key Points

• Epidemic declared: increase in the number of confirmed cases over the past 6 weeks across the entire country

• 833 cases of dengue reported since the start of the outbreak, including 633 confirmed cases in 2020

• Most active viral circulation hotspots: Mtsamboro, Mamoudzou, Chirongui, Bandrele

• DENV-1 serotype predominant (DENV-2 serotype identified in 2 imported cases)

• Rainy season conducive to an increase in the mosquito population

• Dengue epidemics in the Indian Ocean region: risk of importation of new cases and serotypes.