World Dengue Day is observed each year on 15 June to raise awareness of dengue, a neglected tropical disease and one of the fastest-spreading infectious conditions worldwide. Approximately 5.6 billion people, more than half of the world's population, is at risk of dengue, with an estimated 100–400 million infections occurring each year. More about Dengue: who.int/news-room/events/detail/2026/06/15/default-calendar/world-dengue-day-2026 More about neglected tropical diseases: who.int/health-topics/neglected-tropical-diseases#tab=tab_1