Key Points

• Since March 30, 2019, 56 cases of dengue fever have been reported to the Health Surveillance, Alert, and Management Unit (CVAGS) of the Indian Ocean Regional Health Agency (ARS). Of these cases, only 8 were linked to travel outside the department of Mayotte

• Thus, between May 20 and July 12, 41 cases of dengue confirmed by the laboratory at the Mayotte Hospital Center (CHM) were locally acquired (=autochthonous cases). Five cases are under investigation, and two have an uncertain source of infection

• Nearly 80% of autochthonous cases are located in the municipality of Mamoudzou (32 out of 41)

• Within the municipality of Mamoudzou, the villages of Cavani, M’Tsaperé, and Doujani are the hardest hit: they account for 73% of autochthonous cases (30 out of 41)

• The other locally acquired cases are scattered throughout the territory (north, south, and center of the island): Dzaoudzi, Koungou, Mtsamboro, Sada, Bandrélé, Boueni, and Tsingoni.

• The DENV1 serotype is predominant

• In this context, seeking medical care is recommended at the first signs of illness to enable early diagnosis of dengue and facilitate rapid intervention by the ARS vector control service around cases to limit the spread of dengue throughout the department

• Mobilizing the community and key stakeholders in the fight against mosquitoes, the disease’s vectors, is essential