In 2020, 1,376 imported cases of arboviral diseases transmitted by Aedes albopictus mosquitoes were reported in mainland France, broken down as follows:

• 1,357 cases of dengue (including 89 probable cases)

• 16 cases of chikungunya (including 9 probable cases)

• 3 cases of Zika virus infection (including 2 probable cases)

The areas of origin for the imported dengue cases were primarily the French Antilles, where a major epidemic was raging, with 53% of dengue cases originating from Martinique and 28% from Guadeloupe.

Six local dengue outbreaks totaling 13 cases were identified in mainland France:

• Three outbreaks in Provence-Alpes-Côte d’Azur (PACA) with no link between them and for which no primary imported case could be identified (an imported case that initiated local transmission).

• Three very limited outbreaks, with only one locally transmitted case identified per episode, in Occitanie.