West Nile, il virus delle zanzare in Italia in anticipo a causa del caldo

L’estate rovente e la primavera già più calda del solito hanno fatto comparire gli insetti portatori dell’infezione prima del dovuto. Gioia Capelli, direttrice sanitaria dell'Istituto Zooprofilattico delle Venezie, sottolinea come nel 2022 i casi potrebbero essere particolarmente elevati. È però difficile fare previsioni: rispetto ad altre annate con numeri alti, come il 2018, inverno e primavera sono stati particolarmente scarsi di piogge. Una circostanza che potrebbe limitare il proliferare di zanzare

epa03367657 A handout image made available on 22 August 2012 from the Centers for Disease Control showing a Culex quinquefaciatus female mosquito . This species is a known vector for West Nile Virus. The female C. quinquefasciatus mosquito is known as one of the many arthropodal vectors responsible for spreading the West Nile virus to human beings through their bite when obtaining a blood meal. Mosquitoes of the Culex species lay their eggs in the form of egg rafts that float in still or stagnant water. The mosquito lays the eggs one at a time sticking them together in the shape of a raft. An egg raft can contain from 100 to 400 eggs. The eggs go through larval and pupal stages and feed on micro-organisms before developing into flying mosquitoes. The CDC is reporting that there have currently been 1,100 cases of West Nile Virus reported in the US in 2012, more than ever reported at this point in the year since the virus was first recorded in the US in 1999. EPA/JIM GATHANY / CENTERS FOR DISEASE CONTROL / HANDOUT HANDOUT EDITORIAL USE ONLY/NO SALES

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L’estate rovente, già preceduta da una primavera più calda del solito, hanno aperto in anticipo la stagione delle zanzare. Tra queste, anche quelle portatrici del virus West Nile, che durante l'ultimo mese ha fatto registrare diversi ricoveri e quattro morti per complicazioni legate all’infezione nel Nord Italia

GUARDA IL VIDEO: West Nile, Iss: "In Italia 15 casi e 4 morti per febbre"

epa03367655 A handout image made available on 22 August 2012 from the Centers for Disease Control showing a Culex quinquefaciatus female mosquito feeding on human blood. This species is a known vector for West Nile Virus. The female C. quinquefasciatus mosquito is known as one of the many arthropodal vectors responsible for spreading the West Nile virus to human beings through their bite when obtaining a blood meal. Mosquitoes of the Culex species lay their eggs in the form of egg rafts that float in still or stagnant water. The mosquito lays the eggs one at a time sticking them together in the shape of a raft. An egg raft can contain from 100 to 400 eggs. The eggs go through larval and pupal stages and feed on micro-organisms before developing into flying mosquitoes. The CDC is reporting that there have currently been 1,100 cases of West Nile Virus reported in the US in 2012, more than ever reported at this point in the year since the virus was first recorded in the US in 1999. EPA/JIM GATHANY / CENTERS FOR DISEASE CONTROL / HANDOUT HANDOUT EDITORIAL USE ONLY/NO SALES

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La prima zanzara positiva quest’anno è stata rinvenuta lo scorso 7 giugno, in provincia di Vicenza

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epa03367649 A handout image made available on 22 August 2012 from the Centers for Disease Control showing an electron micrograph of the West Nile virus.. Experts believe WNV is established as a seasonal epidemic in North America that flares up in the summer and continues into the fall. This fact sheet contains important information that can help you recognize and prevent West Nile virus. The CDC is reporting that there have currently been 1,100 cases of West Nile Virus reported in the US in 2012, more than ever reported at this point in the year since the virus was first recorded in the US in 1999. EPA/CYNTHIA GOLDSMITH / CENTERS FOR DISEASE CONTROL / HANDOUT HANDOUT EDITORIAL USE ONLY/NO SALES

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Negli scorsi anni gli esemplari portatori dell’agente patogeno erano stati identificati dalla rete di sorveglianza da metà di luglio in poi, con picchi ad agosto

West Nile, 88enne morto all'ospedale di Ferrara

epa000236429 (FILES) An undated pictue of a mosquito "Anopheles quadrimaculatus", The authorities of the health department of Florida reported on Tuesday, 20 July 2004, at least four cases of persons infected with the Nile virus in Miami-Dade county. The mosquito ''Anopheles quadrimaculatus'' is the most important vector carrying the malaria virus in the United States, and is a species found in West Nile Virus positive mosquito pools in the USA. EPA/U.S. Centers for Disease Control and Prevention

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La situazione è monitorata. L’Università di Padova, insieme all’Istituto Zooprofilattico Sperimentale delle Venezie e alla direzione Prevenzione della Regione Veneto, ha stilato un rapporto pubblicato su Eurosurveillance, la rivista dello European Centre for Disease Prevention and Control (Ecdc)

Dal Zika al West Nile, tutti i virus trasmessi dalle zanzare

epa03367653 A handout image made available on 22 August 2012 from the Centers for Disease Control showing a transmission electron micrograph (TEM) revealing the presence of West Nile virus virions in a tissue sample. Experts believe WNV is established as a seasonal epidemic in North America that flares up in the summer and continues into the fall. This fact sheet contains important information that can help you recognize and prevent West Nile virus. The CDC is reporting that there have currently been 1,100 cases of West Nile Virus reported in the US in 2012, more than ever reported at this point in the year since the virus was first recorded in the US in 1999. EPA/CYNTHIA GOLDSMITH / CENTERS FOR DISEASE CONTROL / HANDOUT HANDOUT EDITORIAL USE ONLY/NO SALES

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"La presenza del West Nile Virus nel nord Italia, specie in Veneto, non è una novità. Lo si riscontra ininterrottamente dal 2008", ha spiegato Gioia Capelli, co-autrice dello studio e direttrice sanitaria dell'Istituto Zooprofilattico delle Venezie

Crisanti: "West Nile grave in 1 caso su 200. Evitare le punture di zanzara"

FERRARA - MORTO UOMO DOPO 8 GIORNI DI COMA PER MALATTIA TRASMESSA DA ZANZARA - LA PERSONA AVEVA CONTRATTO IL VIRUS WEST NILE TRASMESSO DALLE ZANZARE - ALTRE QUATTRO PERSONE CONTAGIATE DI CUI UNO IN CONDIZIONI CRITICHE

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"In alcune stagioni – ha detto Capelli - c'è stata una circolazione minore, in altre il virus si è diffuso di più: per esempio nel 2018, quando si sono registrati circa 200 casi nell'uomo solo in Veneto"

L’inizio precoce della stagione calda potrebbe ora far temere un’annata con numeri di casi particolarmente elevati

LOUISVILLE, KY - AUGUST 25: Culex pipiens, a common mosquito species, is seen through the microscope of Matthew Vanderpool, environmental health specialist and entomologist for the Louisville Metro Department of Public Health and Wellness on August 25, 2021 in Louisville, Kentucky. Vanderpool specializes in mosquito control, a public health process that involves placing traps to collect specimen, identifying various mosquito species, and testing the samples for mosquito-borne diseases. Lab technologists test for Saint Louis encephalitis, West Nile virus, La Crosse encephalitis, and Eastern equine encephalitis.(Photo by Jon Cherry/Getty Images)

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Non è però così facile fare previsioni, dice Capelli. Che sottolinea come nel 2018 l’estate fu preceduta da un inverno e da una primavera piovosi, creando condizioni ideali per il proliferare delle zanzare

LOUISVILLE, KY - AUGUST 25: Matthew Vanderpool, environmental health specialist and entomologist for the Louisville Metro Department of Public Health and Wellness, is fed upon by a female mosquito on August 25, 2021 in Louisville, Kentucky. Vanderpool specializes in mosquito control, a public health process that involves placing traps to collect specimen, identifying various mosquito species, and testing the samples for mosquito-borne diseases. Lab technologists test for Saint Louis encephalitis, West Nile virus, La Crosse encephalitis, and Eastern equine encephalitis.(Photo by Jon Cherry/Getty Images)

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Quest’anno la pioggia è caduta poco sull’Italia. "La scarsità d'acqua potrebbe contenere la crescita del numero di zanzare", ha specificato Capelli

LOUISVILLE, KY - AUGUST 25: Mosquitos are seen clinging to the netting in a gravid mosquito trap placed by the Louisville Metro Department of Health and Wellness on August 25, 2021 in Louisville, Kentucky. This trap is part of the Health Departments efforts in mosquito control, a public health process that involves placing traps to collect specimen, identifying various mosquito species, and testing the samples for mosquito-borne diseases. Lab technologists test for Saint Louis encephalitis, West Nile virus, La Crosse encephalitis, and Eastern equine encephalitis.(Photo by Jon Cherry/Getty Images)

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In ogni caso, l’invito alla cittadinanza che vive nelle zone interessate dal fenomeno è quello di proteggersi, per esempio con l'uso di repellenti. La zanzara si muove poi soprattutto di notte: "Il rischio si ha dal tramonto all'alba", sottolinea Capelli