Key Points

West Nile

• As of October 17, 2023, 31 locally acquired human cases (confirmed or probable) have been identified (onset of symptoms between mid-July and late September): 24 in Gironde, 5 in Charente-Maritime, and 2 in Charente. Investigations are underway for 8 other individuals. In addition, 16 equine cases have been reported (12 in Gironde and 4 in Charente-Maritime) and 6 avian cases (in Charente-Maritime). These cases indicate circulation of the West Nile virus in Gironde, Charente-Maritime, and Charente. In addition, a bird case co-infected with the Usutu virus and the West Nile virus has been identified in Charente-Maritime.

Usutu

• In early August 2023, two human cases of Usutu virus infection were identified in the region by the National Reference Center for Arboviruses. As of October 17, 2023, six locally acquired human cases had been identified, including four residing in Gironde, one in Landes, and one in Charente-Maritime. In addition, two avian cases were reported in Charente-Maritime and Haute-Vienne. The Usutu virus is therefore circulating in Gironde, Charente-Maritime, Haute-Vienne, and Landes.

Chikungunya, dengue, Zika

• From May 1 to October 13, 2023, 114 imported cases of dengue and 4 imported cases of chikungunya were identified in the region (compared to 30 imported cases of dengue and 3 imported cases of chikungunya from May 1 to November 30, 2022). To limit the emergence of local transmission chains, 163 entomological surveys (mosquito searches) and 110 vector control treatments were carried out around cases residing in or passing through the region.