Italy reports over 650 West Nile virus cases this year as warming temperatures extend mosquito season across Europe
Italy has reported more than 650 West Nile virus infections so far in 2026, accounting for roughly half of all cases recorded in Europe. Health researchers attribute the spread partly to rising temperatures that extend the mosquito transmission season and allow the virus to reach areas previously unaffected. West Nile has been considered endemic in Italy since 2020.
Single source · Not corroborated
Italy's National Institute of Health (ISS) has recorded more than 650 West Nile virus infections this year, a figure that represents approximately half of all European cases. Researchers describe the current totals as broadly in line with recent seasons, reflecting a pattern that has intensified since the virus became endemic in the country in 2020.
Antonino Bella, a researcher at the ISS, said that higher temperatures linked to climate change help mosquitoes reproduce and extend the transmission season, increasing the likelihood that infected mosquitoes will spread the virus to people. He noted that the season can now sometimes last as late as November, and that areas once largely unaffected are increasingly reporting infections.
Marc-Alain Widdowson, who leads the Pandemic Threats, Communicable Diseases, and AMR Division at the World Health Organization's Europe office, said there is no doubt that warming weather will expand the period of viral and vector replication across more countries. He cautioned, however, that climate change should not be treated as the sole driver, adding that a warming climate means a longer mosquito season and better survival conditions for the virus itself. He also cited loss of biodiversity and changes in land use as contributing trends.