A study published in the journal Current Biology on September 11, 2023, confirmed the first documented establishment of the invasive fire ant Solenopsis invicta in Europe. Researchers discovered a mature population of these ants in Sicily, near the city of Syracuse, with 88 nests found across about 4.7 hectares during the winter of 2022–2023. The fire ant, known for its painful sting similar to that of a wasp, can cause severe allergic reactions, including anaphylactic shock, a life-threatening condition requiring immediate medical attention. The species has been a persistent problem in the United States since the 1930s, when it was accidentally introduced via a cargo ship from South America. Despite extensive efforts, the ants have never been fully eradicated, and they continue to cause significant economic and health challenges. According to climate models, half of European cities are at risk of invasion, and the spread of the fire ant could have devastating effects on biodiversity, agriculture, and human health. In the U.S., the ants are known to dominate ecosystems, displacing native species and harming small wildlife like frogs and lizards. Their venom can also cause severe reactions in humans, making areas infested with the ants difficult to access for hikers and farmers. The discovery in Sicily was largely accidental, driven by the complaints of local residents who had been stung repeatedly. Mattia Menchetti, an entomologist at the Institute of Evolutionary Biology in Barcelona and lead author of the study, explained that the ants were found "almost by chance" after residents sent photos of the insects. Genetic testing revealed that the Sicilian population originated from the United States, China, and Taiwan. A nearby freight port, located just a few kilometers from the first nests, suggests that global trade and wind patterns may have facilitated the ants' spread. Efforts to prevent the spread of invasive species have already been taken at the policy level. In 2022, the European Union added Solenopsis invicta to its list of invasive alien species of concern, prohibiting its import, transport, and cultivation on European soil. However, the researchers’ findings suggest that the fire ant may have already been present in Sicily for several years. Residents began reporting frequent stings as early as 2017, indicating that the population had been established long before the official discovery. With climate change expected to expand the ants' suitable habitat, the situation presents a growing challenge for European ecosystems and public health.