RT Journal Article SR Electronic(1) A1 Cilla, G A1 Basterretxea, M A1 Artieda, J A1 Vicente, D A1 PĂ©rez-Trallero, E YR T1 JF VO OP UL https://www.eurosurveillance.org/content/10.2807/esm.09.05.00468-es