Key Points

• In the Grand Est region, 34 imported cases of chikungunya and 15 imported cases of dengue were identified between May 1 and July 15, 2025. The first locally acquired case of chikungunya in the Grand Est region was also recently identified in the Bas-Rhin department.

• To limit the risk of local transmission, 12 entomological surveys and 4 vector control treatments were carried out in the vicinity of these cases.