West Nile virus is an Arbovirus transmitted to humans through the bite of an infected mosquito West Nile virus is a viral infection transmitted to humans through the bite of an infected mosquito. Human infection is asymptomatic in over 80% of cases; in the remaining 20%, the symptoms are those of a pseudo-influenza syndrome. In 0.1% of all cases, the viral infection may trigger neurological symptoms resembling those of meningitis or meningoencephalitis. National and international scientific evidence has demonstrated the effectiveness of systematic surveillance to capture vector mosquitoes and active surveillance of wild birds to provide early information on the circulation of West Nile Virus.
Timely detection of viral circulation is crucial for the immediate activation of measures to prevent transfusion-related transmission of WNV.
Decrees (Italian Text)
14/05/2025 – Circolare CNS – Indicazioni per la sorveglianza e la prevenzione della trasmissione del West Nile Virus e Usutu mediante la trasfusione di emocomponenti labili nella stagione estivo-autunnale 2025
Allegato 1 – Attivazione delle misure di prevenzione della trasmissione trasfusionale del WNV 2025
Allegato 2 – Gestione degli esiti del test di screening per WNV
Allegato 3 – Piano nazionale di prevenzione, sorveglianza e risposta alle Arborivirosi 2020-2025
Allegato 3a – Aggiornamento/rimodulazione per l’anno 2025 del Piano Regionale di Pre-venzione, sorveglianza e risposta alle Arbovirosi
22/07/2025 – Ministry of Health Circular – Prevention, surveillance, and response interventions regarding the circulation of West Nile and Usutu viruses – 2025 vector season
16/10/2025 – Circolare CNS – Proroga misure di prevenzione della trasmissione dell’infezione da West Nile virus mediante la trasfusione di emocomponenti labili nella stagione estivo-autunnale 2025
26/11/2025 – Circolare CNS – Sospensione dei provvedimenti per la prevenzione della trasmissione dell’infezione da West Nile virus nella stagione estivo-autunnale 2025
30/04/2026 – Nota Ministero della Salute – ARBOVIROSI: Prevenzione, sorveglianza ed interventi in risposta alla circolazione delle arbovirosi oggetto di sorveglianza del Piano Nazionale di revenzione, sorveglianza e risposta alle Arbovirosi, PNA 2020-2025 – stagione vettoriale 2026.
Prevention measures
23/06/2025 – WNV Prevention Map – Provinces of Venice and Oristano
03/07/2025 – WNV prevention Map – Province of Modena
04/07/2025 – WNV Prevention Measures – Province of Turin
04/07/2025 – WNV Prevention Measures – Provinces of Parma and Piacenza
04/07/2025 – WNV Prevention Measures – Province of Rovigo
09/07/2025 – WNV Prevention Measures – Provinces of Lodi and Pavia
10/07/2025 – WNV Prevention Measures – Province of Cremona
11/07/2025 – WNV Prevention Measures – Province of Padova
11/07/2025 – WNV Prevention Measures – Provinces of Reggio Emilia and Mantova
14/07/2025 – WNV Prevention Measures – Western Attica and Piraeus (Greece) and Sălaj (Romania)
16/07/2025 – WNV Prevention Measures – Province of Latina
17/07/2025 – WNV Prevention Measures – Province of Forlì-Cesena
18/07/2025 – WNV Prevention Measures – Province of Lecce
18/07/2025 – WNV Prevention Measures- Province of Ferrara
18/07/2025 – WNV Prevention Measures – Province of Verona
21/07/2025 – WNV Prevention Measures – Province of Treviso
21/07/2025 – WNV Prevention Measures – Province of L’Aquila
22/07/2025 – WNV Prevention Measures – Province of Naples
22/07/2025 – WNV Prevention Measures – Province of Caserta
24/07/2025 – WNV Prevention Measures – Province of Udine
25/07/2025 – WNV Prevention Measures – Province of Novara
25/07/2025 – WNV Prevention Mesaures – Province of Milan
25/07/2025 – WNV Prevention Measures – Provinces of Bologna and Ravenna
25/07/2025 – WNV Prevention Measures – Provinces of Lecco and Varese
28/07/2025 – WNV Prevention Measures – Province of Rome
29/07/2025 – WNV Prevention Measures – Province of Frosinone
31/07/2025 – WNV Prevention Measures – Province of Vicenza
31/07/2025 – WNV Prevention Measures – Province of Sassari
31/07/2025 – WNV Prevention Measures – Province of Foggia
01/08/2025 – WNV Prevention Measures – Province of Brescia
01/08/2025 – WNV Prevention Measures – West Athens, Elis (Greece)
01/08/2025 – WNV Prevention Measures – Provinces of Asti and Vercelli
04/08/2025 – WNV Prevention Measures – Province of Sud Sardegna
04/08/2025 – WNV Prevention Measures – Sofia (Bulgaria), Dolj (Romania), East Attica, Evros, Larissa (Greece) and Var (France)
05/08/2025 – WNV Prevention Measures – Province of Monza Brianza
06/08/2025 – WNV Prevention Measures – Province of Catania
06/08/2025 – WNV Prevention Measures – Province of Matera
06/08/2025 – WNV Prevention Measures – Province of Cuneo
07/08/2025 – WNV Prevention Measures – Province of Alessandria
08/08/2025 – WNV Prevention Measures – Province of Reggio Calabria
08/08/2025 – WNV Prevention Measures – Province of Biella
11/08/2025 – WNV Prevention Measures – Province of Isernia
11/08/2025 – WNV Prevention Measures – provinces of Bergamo and Genoa
11/08/2025 – WNV Prevention Measures – Karditsa, Trikala, North Athens (Greece); Pest (Hungary); Bouches-du-Rhône (France); Vrancea (Romania)
11/08/2025 – WNV Prevention Measures – province of Catanzaro
11/08/2025 – WNV Prevention Measures – province of Salerno
13/08/2025 – WNV Prevention Measures – provinces of Syracuse and Caltanissetta
14/08/2025 – WNV Prevention Measures – province of Cosenza
18/08/2025 – WNV Prevention Measures – province of Campobasso
18/08/2025 – WNV Prevention Measures – Central Athens, Pella (Grecia); Seine-Saint Denis (France); Bucharest (Romania); Belgrade, South Bačka, Pomoravlje, Central Banat (Serbia); Cáceres (Spagna)
18/08/2025 – WNV Prevention Measures suspended – province of Genoa
22/08/2025 – WNV Prevention Measures – Berat, Elbasan, Alessio (Albania) Braničevo, South Banat, Šumadija (Serbia)
22/08/2025 – WNV Prevention Measures – Province of Genoa
22/08/2025 – WNV Prevention Measures – Province of Messina
22/08/2025 – WNV Prevention Measures – Province of Pordenone
26/08/2025 – WNV Prevention Measures – Province of Avellino
29/08/2025 – WNV Prevention Measures – Province of Arezzo
01/09/2025 – WNV Prevention Measures – Val-d’Oise, Vaucluse (France), Imathia, Arta, Preveza, Achaia (Greece), Budapest, Heves (Hungary), Prahova, Galati (Romania), Moravica, Podunavlje, Raška, West Bačka (Serbia), Badajoz (Spain).
02/09/2025 – WNV Prevention Measures – Province of Gorizia
02/09/2025 – WNV prevention Measures – Province of Barletta-Andria-Trani (BAT)
03/09/2025 – WNV Prevention Measures – Province of Nuoro
03/09/2025 – WNV Prevention Measures- Province of Sondrio
03/09/2025 – WNV Prevention Measures – Province of Como
04/09/2025 – WNV Prevention Measures – Province of Chieti
04/09/2025 – WNV Prevention Measures – Province of Grosseto
04/09/2025 – WNV Prevention Measures – Province of Savona
05/09/2025 – WNV Suspension of preventive measures – Province of Savona
05/09/2025 -WNV Prevention Measures – Puy de Dome (France), Aetolia-Acarnania, Korinthia (Greece), Ilfov, Teleorman, Timiș (Romania), Severnobanatska Oblast (Serbia), Bacs-Kiksun (Hungary).
09/09/2025 – WNV Prevention Measures – Province of Benevento
10/09/2025 – WNV Prevention Measures – Province of Florence
10/09/2025 – WNV Prevention Measures – Province of Siena
12/09/2025 – WNV Prevention Measures – Alicante (Spagna), Çanakkale (Turchia), Alba
e Brǎila (Romania).
15/09/2025 – WNV Prevention Measures – Province of Brindisi
16/09/2025 – WNV Prevention Measures – Province of Macerata
17/09/2025 – WNV Prevention Measures – Province of Ancona
19/09/2025 – WNV Prevention Measures – Val-de-Marne (France), Eubea, Laconia, Messenia (Greece), Peć (Kosovo), Iași, Vâlcea (Romania), Almería (Spain).
19/09/2025 – WNV Prevention Measures – Province of Lucca
22/09/2025 – WNV Prevention Measures – Province of Fermo
26/09/2025 – WNV Prevention Measures – Haute-Garonne, Hauts de Seine (France), Thessaloniki (Greece), Skopje (North Macedonia)
01/10/2025 – WNV Prevention measures – province of Rimini
03/10/2025 – WNV Prevention Measures – Split-Dalmatia, Koprivnica-Križevci, Osijek-Baranja (Croatia), Ardèche, Paris and Puy-de-Dôme (Francia), Heraklion (Greece), Cluj (Romania) e Sirmia (Serbia)
09/10/2025 – WNV Prevention Measures – province of Ragusa
09/10/2025 – WNV Prevention Measures – province of Perugia
13/10/2025 – WNV Prevention Measures – Lefkada (Greece); Csongrád-Csanád, Jász-Nagykun-Szolnok (Hungary)
16/10/2025 – WNV Prevention Measures – Metropolitan City of Cagliari
16/10/2025 – WNV Prevention Measures – Province of Verbano-Cusio-Ossola
17/10/2025 – WNV Prevention Measures – Tarn and Garonne; Yvelines (France), Botoşani, Dâmboviţa, Sibiu (Romania)
22/10/2025 – WNV Prevention Measures – Province of Palermo
24/10/2025 – WNV Prevention Measures- Essonne, Seine Maritime (France), Berlin (Germany)
07/11/2025 – WNV Prevention Measures – Seville (Spain)
14/11/2025 – WNV Prevention Measures – Aschaffenburg (Germany); Hajdú-Bihar (Hungary)
12/12/2025 – Extraordinary Prevention Measures – Province of Naples
23/12/2025 – Extraordinary Prevention Measures Suspension – Province of Naples
23/12/2025 – Extraordinary Prevention Measures – province of Agrigento
02/01/2026 – Extraordinary Prevention Measures Suspension – provine of Agrigento