Health. Two indigenous cases and 45 imported cases of chikungunya in the Grand Est region since May 1

According to the latest report on the enhanced surveillance of arboviruses (dengue, chikungunya, Zika, and West Nile virus infections caused by the tiger mosquito), coordinated by Santé publique France with the Regional Health Agencies (ARS), 966 imported cases of chikungunya were recorded in France (45 in the Grand Est), 894 cases of dengue (32 in the Grand Est) and seven cases of Zika (two in the Grand Est) were identified between May ¹ and September 8, 2025. The number of indigenous cases of chikungunya remains at two, with two cases recorded in the Bas-Rhin, on June 26 in Lipsheim and on August 8 in Strasbourg or Ostwald. The period of enhanced vigilance will end in France on November 30, probably before in Alsace, the risk of infection disappearing when the temperature drops below 15 °C.