Overview

• ECDC reports a record 27 chikungunya outbreaks in Europe this year, including the first locally acquired case in France’s Alsace, and cautions that longer, more intense transmission is becoming the norm.
• West Nile virus detections have expanded to new areas in Italy and Romania, with Europe recording its highest case count in three years and a seasonal peak expected in late summer.
• Dengue set a record in 2024 with more than 14 million reported cases and nearly 12,000 deaths, with a further 3.6 million cases and over 1,900 deaths reported in the first half of 2025 across 94 locations, including outbreaks in Pacific islands.
• Malaria continues to exact a heavy toll, with the WHO estimating 263 million cases and 597,000 deaths worldwide in 2023.
• ECDC has released ready-to-use guidance for chikungunya, dengue, and Zika alongside separate West Nile recommendations, while clinicians emphasize early testing to distinguish infections and trigger vector-control measures; a chikungunya vaccine exists, but none is available for West Nile.