First indigenous case of dengue fever of the year in France reported in Hérault

This is the first recorded in France since the beginning of 2024. An indigenous case of dengue fever was reported on Monday July 8 in Hérault by the regional health agency (ARS) of Occitanie. “The sick person has been taken care of and his state of health does not give rise to concern,” specified the ARS in a press release, in which it announced that it had deployed “preventive actions” in the municipalities of Montpellier and Pérols, for “to prevent the spread of the virus locally”.

Dengue fever is a viral disease that causes a high fever and, rarely, progresses to a more serious form, including bleeding. In about 0.01% of cases, it results in death.

The ARS also announces that a mosquito control action is taking place at the beginning of the week in order to “to eliminate larval breeding sites and adult mosquitoes in the places of residence and passage of the sick person”. A local survey will allow:“identify other possible sick people”. A “native case” means that the person has not recently traveled to areas where this virus, transmitted from person to person by tiger mosquitoes (Aedes albopictus), is widely circulating, such as the Antilles.

The person was probably infected on site after being bitten by a tiger mosquito, whose presence has been increasing for nearly 20 years in France and Corsica, in a context facilitated by global warming. In 2023, France had recorded around fifty indigenous cases of dengue, after a record of 66 in 2022.

In mid-April, health authorities had warned of a situation “unpublished” in France, linked to an outbreak of dengue fever in the Americas and the Caribbean, and called for increased vigilance, especially in the run-up to the Olympic Games, which are favorable to the mixing of populations.