Epidemiological summary

Since the beginning of 2025, and as of 10 December 2025, 14 countries in Europe reported human cases1 of West Nile virus infection: Albania, Bulgaria, Croatia, France, Germany, Greece, Hungary, Italy, Kosovo*, North Macedonia, Romania, Serbia, Spain and Türkiye.

The current report in Table 1 includes the number of probable and confirmed cases of WNV infections per NUTS3 region. However, these figures are preliminary and should be interpreted with caution as they may be revised by the countries as more information becomes available. Consequently, no totals are provided. For further details on case numbers, please refer to the joint monthly report, which offers a more detailed analysis.

As further cases are unlikely given the current unfavourable seasonal weather conditions for vector-borne transmission, ECDC concludes its weekly reports for the 2025 season.

Please note: The table and map in this report contain countries and areas where human West Nile virus infection cases were reported to EpiPulse Cases.

Introduction

The European Centre for Disease Prevention and Control (ECDC) provides a weekly overview of human cases of West Nile virus (WNV) infection to support the competent authorities responsible for blood safety. This overview can aid decisions on the deferral or testing of blood donors who may have been exposed to the virus, in accordance with Commission Directives 2004/33/EC and 2014/110/EU.

West Nile virus infection in humans is a notifiable disease at the EU level and cases are reported in accordance with the EU case definition. The table and map in this report show the countries and areas where human cases of WNV infection have been reported to the European surveillance portal for infectious diseases (EpiPulse Cases).

More information on the occurrence of WNV infection among humans in Europe2, as well as WNV outbreaks among equids and birds, is available in the joint monthly report produced by ECDC and the European Food Safety Authority (EFSA).

Here we present the weekly report as of 10 December 2025.

Overview of West Nile virus cases in EU/EEA and EU-neighbouring countries

Table 1. Countries and regions with locally acquired human cases of West Nile virus infections in 2025 as of 10 December 2025.

(*) Compared to the previous weekly report.

Geographical distribution

Figure 1. Distribution of locally acquired human West Nile virus infections in 2025 as of 10 December 2025 .

Download the data

Download the dataset for West Nile virus surveillance.

Note that this dataset reflects the weekly update on the cases reported, and each row should be interpreted as the total for each country on the corresponding week.

  1. Cases acquired within the reporting country.↩︎

  2. EU/EEA countries and selected EU-neighbouring countries (Albania, Bosnia and Herzegovina, Kosovo*, Montenegro, North Macedonia, Serbia and Türkiye).

    *This designation is without prejudice to positions on status and is in line with UNSCR 1244/1999 and the ICJ Opinion on the Kosovo declaration of independence.

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