1. Pediatric Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
2. Neonatal Intensive Care Unit, Faculty of Medicine, University of Ioannina, 45500 Ioannina, Greece
3. Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milan, Italy
4. Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Medicine and Pharmacy, 400337 Cluj-Napoca, Romania
5. Pediatric Allergy Outpatient Clinic, Department of Pediatrics, “Karamandaneio” Children’s Hospital of Patra, 26331 Patras, Greece
6. 2nd Department of Neonatology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, “Papageorgiou” General Hospital of Thessaloniki, 56403 Thessaloniki, Greece
7. Pediatric Allergy Outpatient Clinic, Department of Pediatrics, Venizeleion General Hospital of Heraklion, 71409 Heraklion, Greece
8. Pediatric Infectious Unit, Department of Pediatrics, University Hospital of Ioannina, 45500 Ioannina, Greece
9. Allergy Unit, 2nd Pediatric Clinic, University of Athens, 11527 Athens, Greece
10. Department of Paediatrics and Child Health, University College Cork, T12 K8AF Cork, Ireland
11. Department of Abilities Human Sciences, Iuliu Hatieganu University of Medicine and Pharmacy, 40012 Cluj-Napoca, Romania