Key Points

Chikungunya, Dengue, and Zika

• Since the start of enhanced surveillance (May 1), 45 imported cases (+12 since the last update) have been identified in the region: 27 cases of chikungunya, 17 cases of dengue, and 1 case of Zika.

• While the chikungunya outbreaks in Réunion and the dengue outbreaks in the Antilles continue to impact surveillance in mainland France, the decline in viral circulation in these territories, particularly in Réunion, is reflected in the number of imported cases reported in recent days.

Heat Wave

• The surveillance and prevention system for heat-related health effects begins on June 1.

Pollen exposure, which may pose an allergy risk

• In the Provence-Alpes-Côte d’Azur region, the pollen index, established by Atmo France and accredited air quality monitoring associations, is at a high level, primarily due to grass pollen.

• Allergy-related activity at SOS Médecins clinics is high.

Monthly report on reportable diseases

• Update on reports of Legionnaires’ disease, hepatitis A, invasive meningococcal disease (IMD), measles, and foodborne illness outbreaks (FBO) in Provence-Alpes-Côte d’Azur: 46 reports in April 2025, including 12 cases of Legionnaires’ disease, 11 cases of hepatitis A, no cases of IMD, 21 cases of measles, and 2 foodborne illness outbreaks.

• The number of measles cases reported in the first four months of 2025 (69) exceeds the total number of cases reported in 2024 (63).