EU countries have reported 1,715 locally acquired human cases of West Nile virus (WNV) infection as of 7 October 2026, the highest number ever recorded.
Italy has reported 748 cases, remaining the most affected country, the European Centre for Disease Prevention and Control reported on Thursday.
Greece and France have also reported their highest-ever numbers of human WNV cases, it added.
There is “no indication of increased severity” this year despite the record caseload, with the proportions of people hospitalised, developing neurological symptoms or dying below levels seen over the past decade, the ECDC said. A total of 130 people have died so far this season.
“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,” said Ole Heuer, a head of unit at the ECDC.
“Earlier detection, greater awareness and effective mosquito control can help us reduce the impact of the virus as it spreads to new areas,” he added.
Virus detected further north
WNV has been detected in new parts of Europe, including in people and animals in Belgium and the Netherlands, indicating the virus is circulating further north.
The Netherlands has reported 59 human cases so far this year, while Belgium has reported 15 — the first locally acquired human WNV infections recorded in the country.
“West Nile virus is a clear example of why a cross-sector approach is essential,” said Céline Gossner, a senior expert at ECDC, in the same statement.
The virus circulates between mosquitoes and birds and can cause disease in people and horses, meaning public health, veterinary and environmental authorities need to work together, she added.
People in areas where WNV is circulating can reduce their risk of infection 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 people with weakened immune systems, who are at greater risk of developing severe symptoms.
Although conditions for transmission are becoming less favourable as summer ends, the virus may continue to spread at a lower level in the coming weeks and additional cases are still expected.
The ECDC called for strong surveillance systems, rapid information exchange across sectors, early detection, and mosquito control combining monitoring, reduction of breeding sites and targeted measures.
