Weekly updates: 2022 West Nile virus transmission season

Map

This weekly report provides an overview of West Nile virus (WNV) epidemiology in the EU/EEA and EU-neighbouring countries during the WNV transmission season (expected to be June-November). The last weekly update for this season was provided on Friday 25 November. Following a One Health approach, WNV infections in humans and outbreaks in equids and birds are included in the report. Visit the dedicated webpages for more information on WNV infections and ECDC’s seasonal WNV surveillance.

Epidemiological summary

Since last week’s update, and as of 23 November 2022, European Union (EU) and European Economic Area (EEA) countries reported 2 human cases of West Nile virus (WNV) infection and no deaths related to WNV infections. Cases were reported by Germany (1) and Greece (1). EU-neighbouring countries reported no human cases of WNV infection and no deaths related to WNV infections.

This week, among the reporting countries, the following NUTS 3 or GAUL1 regions have reported human cases of WNV infection for the first time since the start of this season: Halle (Saale) Kreisfreie Stadt in Germany.

Since the beginning of the 2022 transmission season and as of 23 November 2022, EU/EEA countries have reported 965 human cases of WNV infection in Italy (586), Greece (284), Romania (46), Hungary (14), Germany (11), Croatia (8), Austria (6), Spain (5), France (4) and Slovakia (1). EU/EEA countries have reported 73 deaths in Italy (37), Greece (31) and Romania (5). EU-neighbouring countries have reported 226 human cases of WNV infection in Serbia (226) and 12 deaths in Serbia (12).

During the current transmission season, within the reporting countries, human cases of WNV infection were reported from 107 different NUTS 3 or GAUL 1 regions, of which the following regions reported human cases of WNV infection for the first time ever: Bouches-du-Rhône in France, Harz, Vogtlandkreis and Salzlandkreis in Germany, Pistoia, Lucca, Monza e della Brianza, Biella, Cagliari and Catania in Italy, Brasov in Romania, Moravicki in Serbia and Tarragona and Córdoba in Spain.

Since the beginning of the 2022 transmission season, 93 outbreaks among equids and 314 outbreaks among birds have been reported by EU/EEA countries. Outbreaks among equids have been reported by Italy (44), Germany (15), Greece (9), Croatia (8), Spain (6), France (5), Hungary (3), Portugal (2) and Austria (1). Outbreaks among birds have been reported by Italy (249), Germany (51), Spain (9), Austria (2), Croatia (2) and Hungary (1).

Sources

Data on human cases are collected via The European Surveillance System (TESSy) managed by ECDC. Only locally acquired cases with known place of infection are included in this report. The following EU-neighbouring countries report human cases of WNV infection to ECDC: Albania, Kosovo*, Montenegro, North Macedonia, Serbia and Turkey.

Animal data (i.e. outbreaks among equids and birds) are collected through the Animal Disease Information System (ADIS) of the European Commission. Reporting of WNV in equids and birds is mandatory at the EU/EEA level.

The distribution of human infections covers EU/EEA and EU-neighbouring countries, whereas outbreaks among equids and birds covers only EU/EEA countries.

* 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

Weekly maps

Please note that due to technical reasons no static maps will be published this week. Also, the maps in the WNV dashboard have not been updated for weeks 46 and 47.

Interactive dashboard

The interactive dashboard is available following the “View in full screen” link further below.

Also, due to a technical problem, the dashboard is unable to show the results for week 46 and week 47 graphically. However, the updated data is downloadable from the ‘About the data’ section and from the link below.

Changes from week 45 are that one additional human case was reported in Leipzig, Kreisfreie Stadt in Germany. Two new outbreaks in equids were reported, both in one newly affected area in Greece (Arta, Preveza) and four new outbreaks in birds, all in areas previously affected this season.

Changes from week 46 are that one additional human case was reported in Larisa in Greece, and one in Halle (Saale), Kreisfreie Stadt in Germany. One new outbreak in equids was reported in Italy in Pordenone (previously affected), and three new outbreaks in birds, all in areas in Italy previously affected this season.

Download the data

Download the weekly data set for West Nile virus epidemiology.

Download weekly WNV data

Case definition

EU case definition for diagnosing and reporting West Nile virus infection, under Decision No 2119/98/EC of the European Parliament and of the Council.

See West Nile virus infection

ECDC publishes weekly WNV epidemiological updates during the WNV transmission season, including the geographical distribution of human cases in the EU/EEA and EU neighbouring countries. In addition, ECDC includes maps in its epidemiological updates highlighting areas where WNV outbreaks among equids have been reported. Read more