Khadijah Shehu Abdulkareem
Mainland France is facing an unprecedented rise in chikungunya cases this summer, as the tiger mosquito continues to spread across the country. At the same time, US health regulators have suspended the license of a French-made vaccine after reports of serious side effects.
Health authorities have zeroed in on Vitrolles, a suburb of Aix-en-Provence, where 33 locally transmitted cases have been confirmed — the largest outbreak ever recorded in mainland France. In total, 27 outbreaks involving 154 cases have been reported nationwide this year, according to the national health agency Santé publique France (SPF).
The crisis comes as France’s overseas territory, Réunion Island, struggles with a deadly chikungunya outbreak that began in 2024. The World Health Organization (WHO) estimates that one-third of the island’s population has already been infected.
Warmer Climate Driving Mosquito Spread
Experts warn that climate change is playing a major role in the mosquito-borne disease’s spread. Warmer summers and milder winters in northern Europe mean that the tiger mosquito — which also carries dengue fever — is no longer being killed off during the cold season.
The insect is now established in more than 80 of France’s 101 departments, forcing authorities to intensify mosquito-control measures in affected regions. Dengue cases have also been rising in tandem with chikungunya.
US Suspends French Vaccine
Meanwhile, in a significant setback, the US Food and Drug Administration (FDA) has suspended the license for Ixchiq, a chikungunya vaccine developed by French biotech company Valneva. The decision follows reports of “serious adverse events,” particularly among elderly patients.
Valneva’s vaccine was granted US approval in 2023, marking the first chikungunya vaccine to reach the market. However, both the FDA and the European Medicines Agency are now reviewing its safety profile after the recent reports.
Thomas Lingelbach, Valneva’s chief executive, said the company remains committed to providing the vaccine despite the setback:
“As we determine potential next steps, and as the clear threat of chikungunya continues to escalate globally, Valneva remains fully committed to maintaining access to our vaccine as a global health tool.”
With mosquito populations expanding and outbreaks intensifying, health authorities warn that chikungunya and other tropical diseases may become a recurring challenge for Europe in the years ahead.