1. Department of Paediatrics and Neonatology, Hospital Universitario Fundación Alcorcón, 28922 Madrid, Spain
2. Paediatric Emergency Department, Hospital Universitario La Paz, 28046 Madrid, Spain
3. Department of Paediatrics, Tropical and Infectious Diseases, Hospital Universitario La Paz, 28046 Madrid, Spain
4. IdiPAZ Research Institute, Translational Research Network for Paediatric Infectious Diseases (RITIP), 28029 Madrid, Spain
5. Centre for Biomedical Research in Infectious Diseases (CIBERINFEC), 28029 Madrid, Spain
6. Department of Paediatrics, Autonomous University of Madrid, 28029 Madrid, Spain