Tropical Diseases Like Dengue Fever and Chikungunya Are on the Rise in Europe

As climate change increases temperatures across Europe, invasive mosquitoes are spreading and introducing disease agents that Europeans would usually think about only when traveling to other continents. The Fano outbreak wasn’t the first time dengue had been detected as spreading locally in mainland Europe, but it was significantly larger than previous incidents, with 199 cases detected between mid-August and mid-October of 2024. Over the past few years, European countries have reported outbreaks of other mosquito-borne viruses such as chikungunya, a painful disease that causes joint swelling, and West Nile virus. In a heating world, so-called tropical diseases are no longer restricted to tropical regions—and researchers expect the trend to continue.