title: Letters to the Editors.
authors.affiliation: Department of Pediatrics, Hospital Donostia, San Sebastian, Spain (Pérez-Yarza) Department of Pediatrics, Hospital Vall d’Hebron, Barcelona, Spain (Moreno) Técnicas Avanzadas de Investigación en Servicios de Salud (TAISS), Madrid, España (Lázaro) Division of Infectious Diseases, Department of Pediatrics, University of Texas Southwestern Medical Center and Children’s Medical Center Dallas, Dallas, TX (Ramilo, Mejías).
authors.forename: Eduardo G
authors.initials: EG
authors.lastname: Pérez-Yarza
authors.forename: Antonio
authors.initials: A
authors.lastname: Moreno
authors.forename: Pablo
authors.initials: P
authors.lastname: Lázaro
authors.forename: Octavio
authors.initials: O
authors.lastname: Ramilo
authors.forename: Asunción
authors.initials: A
authors.lastname: Mejías