Public Health & Biodiversity: Réunion’s chikungunya outbreak is now mapped in detail, with genomic surveillance sequencing 3,000+ near-complete viral genomes to show the epidemic likely began with a single introduction and then spread through highly mixed circulation across the island. Sustainable Infrastructure: Réunion’s Roland Garros airport arrivals terminal is cooling without air conditioning, using natural ventilation design—trade winds, roof “waves,” and large ceiling fans—to cut emissions while keeping comfort in humid tropical weather. Local Climate Resilience: The airport’s approach is a practical example of adapting buildings to Reunion’s heat and humidity rather than fighting it with energy-hungry systems. Health Monitoring: The same surveillance work that tracked chikungunya’s evolution also helped explain how the virus later reached other Indian Ocean islands and surged beyond the tropics.