3Family Medicine Group of Pianiga, Venice, Italy consisting of the following medical practitioners: C. Barolo, C. Garzotto, I. Matiello and P. Marcato, Italy, E-mail: vincenzo.baldo@unipd.it
*Corresponding Author:
Professor Vincenzo Baldo, Department of Environmental Medicine and Public Health, Institute of Hygiene,, University of Padua, Via Loredan 18, 35131 Padua, Italy, Fax: +39 049 827 5392 Email: