Ole Heuer, Head of Unit at ECDC, says:
‘The occurrence of West Nile virus varies considerably from year to year and is difficult to predict, but what we can do is ensure we’re prepared. Earlier detection, greater awareness and effective mosquito control can help us reduce the impact of the virus as it spreads to new areas.’
As of 7 October 2026, EU countries have reported 1 715 locally acquired human cases of WNV infection, the highest number ever reported. Italy remains the most affected country, with 748 cases reported. Greece and France reported their highest numbers of human cases of WNV infection ever.
Despite the record number of reported cases, there is currently no indication of increased severity this year. The proportions of reported cases who have been hospitalised, developed neurological symptoms or died remain below the levels observed over the previous decade. So far this season, 130 people have died.
WNV is expanding into new areas of Europe. Recent detections in people and animals in Belgium and the Netherlands show that the virus is now circulating further north, a trend that is expected to continue in the coming years. The Netherlands has reported 59 human cases so far this year. Belgium has reported 15 human cases – the first locally acquired human WNV infections recorded in the country. This highlights the need for surveillance, using a One Health approach across the human and animal health sectors and a certain level of preparedness by countries across the EU.
Céline Gossner, senior expert at ECDC, says:
‘West Nile virus is a clear example of why a cross-sector approach is essential. The virus circulates between mosquitoes and birds and can cause disease in people and horses, so no single sector can address the risk alone. Public health, veterinary and environmental authorities need to work together to understand the risk and respond more effectively.’
The further spread to the virus across Europe means that more people are at risk of infection. Anyone living in or visiting areas where WNV is circulating can reduce their risk by using mosquito repellent, wearing loose-fitting long clothing in the evening and at night, and using window screens, mosquito nets, or air conditioning where appropriate. Protection is particularly important for older adults and those with weak immune systems, who are at greater risk of developing severe symptoms.
Although environmental conditions for WNV transmission are becoming less favourable as the summer ends, it may continue at a lower level in the coming weeks, and additional cases are still expected. Countries across Europe therefore need to make sure they have strong surveillance systems in place, ensure rapid information exchange across sectors, and support early detection. Effective mosquito control needs to combine mosquito monitoring, reduction of breeding sites and targeted control measures, coordinated across public health, veterinary, and environmental authorities. Together with personal protection against mosquito bites, these measures can help reduce the risk of infection.