Chikungunya: More than 300 indigenous cases in mainland France, the epidemic is not over

The number of indigenous cases continues to rise dangerously. In its latest report published on September 3, Public Health France reported 301 cases in mainland France since the beginning of May, twice as many as in mid-August. And this epidemic is not over, since the tiger mosquito, the vector of chikungunya, is active until the end of November. "The growing number of transmission outbreaks confirms the increased risk of indigenous transmission in mainland France," warns the public health agency. "With the persistence of active outbreaks, particularly in tourist areas in the south of France, and the return of summer vacations, the risk of secondary outbreaks in other regions of France is increased." Several major outbreaks, with up to 47 cases, have been identified, notably in Provence-Alpes-Côte d'Azur, Nouvelle-Aquitaine, Occitanie, and Corsica.

Where have indigenous cases been detected this year?

All indigenous cases have been detected since June in these regions: Provence-Alpes-Côte-d'Azur, Corsica, Occitanie, Auvergne-Rhône-Alpes, and for the first time in Nouvelle-Aquitaine, Grand-Est and Bourgogne-Franche-Comté. The main outbreaks with the highest number of cases have been identified:

• in Bouches-du-Rhône in Vitrolles (41 cases),
• in the Var in Fréjus (47 cases),
• in the Alpes-Maritimes in Antibes (38 cases),
• in Dordogne in Bergerac (37 cases),
• in Isère in Eybens (22 cases).

"Such an early start to the mosquito's active season and such a high number of outbreaks have never been observed before," Public Health France stated in a previous report. Since the beginning of 2025, more than 1,870 cases of chikungunya (imported and indigenous) have been detected in mainland France, including 957 between May 1 and September 2 alone, according to Public Health France. In the previous two years, only around thirty cases had been reported, including 0 or 1 indigenous case (contracted on the territory).

What are the latest figures for the epidemic in Réunion and Mayotte?

The chikungunya epidemic is over in Réunion and has declined significantly in Mayotte. The territory has been in an epidemic phase since May 27, 2025, and the number of cases has been declining since July, according to Public Health France. Nearly 1,200 cases have been detected so far, and no deaths have been reported.

In Réunion, a decline in epidemic indicators has been observed since the end of April. The epidemic is now "of low intensity," even though the virus is still circulating and "cases are still being confirmed," according to the latest report from Public Health France published on June 18. Nearly 54,000 cases have been reported on the island since the beginning of the year. The chikungunya epidemic has caused the deaths of a total of 27 people, who were "mainly" over 65 years old and had comorbidities.

How to protect yourself from chikungunya?

Several vaccines against chikungunya exist. Until now, travelers were not recommended to be vaccinated against chikungunya. However, in its 2025 recommendations for travelers , the High Council for Public Health has updated its recommendations regarding chikungunya.

A new vaccine authorized in Europe in February 2025 and then arriving in France in June, called Vimkunya, is now recommended for stays "in an area where an epidemic is known," "in the event of a prolonged stay," or "repeated stays in an area where active circulation of the virus" is observed, in 12-65 year-olds who have comorbidities. Vaccination is only "to be considered" for those over 65 and 12-65 year-olds who do not have comorbidities. It is not currently recommended for pregnant and breastfeeding women due to insufficient data.

Another vaccine, Ixchiq, was already available but is not recommended for travelers. It is only "to be considered" for those aged 12-65 who are not immunocompromised. The European Medicines Agency announced on July 11 that it was once again authorized for use in those over 65 after being contraindicated in this age group. Several serious adverse effects - including 3 deaths - had in fact been recorded during the vaccination campaign implemented in Réunion at the beginning of April, according to the French National Agency for the Safety of Medicines .

Aside from vaccination, the only way to protect yourself from the disease is to avoid mosquito bites by using repellents, mosquito nets, and wearing long, loose-fitting clothing. It is recommended that people living in, visiting, or returning from Reunion Island monitor themselves for symptoms.

Vulnerable people must be particularly vigilant, especially those suffering from chronic illnesses, but also pregnant women and immunocompromised people, and now those over 65, for whom vaccination is not recommended. The disease can indeed be serious in these people. There is currently no specific treatment for chikungunya. The only available treatments are symptomatic, including paracetamol. Part of the population is already immune to chikungunya following the last epidemic in 2005-2006, which affected approximately 260,000 people.