Morales Suárez-Varela, María M.; González Candelas, Fernando; Astray, Jenaro; Alonso, Jordi; Garin, Olatz; Castro, Ady; Galán, Juan Carlos; Baricot, Maretva; Castilla, Jesús; Godoy, Pere; Delgado-Rodríguez, Miguel; Martín, Vicente; Mayoral, José María; Pumarola, Tomás; Quintana, José María; Tamames, Sonia; Llopis González, Agustín; Domínguez, Ángela; CIBERESP Cases; Controls in Pandemic InfluenzaWorking Group, Spain (2014)