Unexpected Increase in Chikungunya Outbreaks Cause Concern When Visiting France and Italy

Since the beginning of 2025, two European countries have reported an unusual number of locally transmitted cases of chikungunya virus disease.

The European Centre for Disease Prevention and Control (ECDC) states that the environmental conditions in the areas of the Europe where Ae. albopictus or Ae. Aedes aegypti mosquitoes are established and currently favourable for chikungunya outbreaks.

As of mid-September 2025, France reported 82 new locally acquired cases of chikungunya, compared to 74 new cases the previous week, while Italy reported 60 new locally acquired cases (compared to 44 new cases the previous week.

In total, France's southern and western coasts have reported about 383 cases, and Italy's northern area has reported 167 local cases this year.

Both countries have also reported cases related to travel.

While the U.S. CDC recently highlighted chikungunya outbreaks in Bangladesh, Kenya, Madagascar, Somalia, and Sri Lanka, the Level 2 Travel Health Advisory did not list France or Italy.

Since the long-term health risks from a chikungunya infection remain unknown, the CDC recommends vaccination for travelers visiting an area with an outbreak.

When departing from the United States in September 2025, travel clinics and pharmacies offer U.S. FDA-approved vaccination services.