1. Department of Epidemiology and Public Health, Yale University School of Medicine, LEPH 606, 60 College Street, New Haven, Connecticut 06510
2. UMR INRA/INSA de Lyon Biologie Fonctionnelle, Insectes et Interactions (BF2I), INSA de Lyon, 20 Avenue Albert Einstein, 69621 Villeurbanne Cedex, France