Where is West Nile fever? Lessons learnt from recent human cases in northern Italy Gobbi, F and Napoletano, G and Piovesan, C and Russo, F and Angheben, A and Rossanese, A and Cattelan, A M and Gallo, L and Valsecchi, M and Piazza, A and Venturi, G and Bisoffi, Z, Eurosurveillance, 14, 19143 (2009), https://doi.org/10.2807/ese.14.10.19143-en