West Nile fever, how to defend against the virus – Chronicle

Milan, July 27, 2018 – The West Nile virus, variant 2 spreads. Italy ranks first in Europe with the highest number of reported incidents (ten cases in Veneto since the beginning of summer). Transmitted by mosquitoes, the West Nile virus goes back over the river Po and its tributaries, according to a study from the University of Milan. This new African disease gets its name (West Nile) from the Uganda District where the virus was first isolated. Men, horses and other mammals can be accidentally infected by mosquitoes come into contact with the blood of birds carrying the infection which represent the reservoir of the virus. Human infection is asymptomatic in 80% of cases, but can cause fever and in one case in 150 causes inflammation (meningoencephalitis) often unfortunately lethal mainly in subjects

In Europe it was known that West Nile was isolated in animals and in sporadic human cases, in 1996 triggered an epidemic in Romania for which variant 1 of the virus was responsible . Then the scenario changes. In 2004, for the first time outside of Africa, a variant of the same virus appears, called WNV-2, isolated from wild birds caught in Hungary. Variant 2 spreads rapidly to the southeast in the Balkan peninsula and around to the eastern Mediterranean : eight years ago, it causes a serious epidemic ] in the north of Greece . Subsequently it also enters Italy

For the prevention of the transmission of the infectious agent, in Italy there exists since 2008 a surveillance plan which provides for the systematic search for the virus, between June and October , in samples of mosquitoes and sentinel animals (birds and horses). After entering Hungary in 2004, it is badumed that the 2 West Nile variant reached Italy ten years ago. From the Adriatic, the virus would have crept into the Po Valley along the most important Italian river axis: to the east, reaching the Po delta and the Veneto and the Penetrating west in Lombardy and Piedmont . During the last season, the epidemic seems to be moved south, along the main tributaries of the Po, frequent stop of migratory birds, potential reservoirs of infection. The origin and means of spread of the West Nile Virus outbreak in Europe were developed by a study of the team of Gianguglielmo Zehender, Professor at the Laboratory of Infectious Diseases of the University of Milan in collaboration with the Universities of Padua and Pavia, and the Zooprofilattici Institutes of Lombardy, Emilia-Romagna and Veneto