1. Servicio de Microbiología-IIS Biodonostia; Hospital Universitario Donostia; San Sebastián Spain
2. Biomedical Research Centre Network for Respiratory Diseases (CIBERES); San Sebastián Spain
3. Servicio de Cirugía Infantil; Hospital Universitario Donostia; San Sebastián Spain
4. Servicio de Pediatría; Hospital Universitario Donostia San Sebastián Spain
5. Department of Preventive Medicine and Public Health; Faculty of Medicine; Basque Country University (UPV/EHU); San Sebastián Spain