1. Department of Pulmonology Franciscus Gasthuis & Vlietland Rotterdam The Netherlands
2. Department of Pulmonology Erasmus Medical Center Rotterdam The Netherlands
3. Department of Pediatric Allergy and Pneumonology Medical University of Warsaw Warsaw Poland
4. Immunology Unit University of Verona and General Hospital Borgo Roma Hospital Verona Italy
5. Università Cattolica del Sacro Cuore Rome Italy
6. Faculty of Medicine University of Belgrade University Children's Hospital Belgrade Serbia
7. Faculty of Medicine and Surgery Respiratory Medicine Catholic University of the Sacred Heart Milan Italy
8. Department of Cardiovascular and Thoracic Sciences Università Cattolica del Sacro Cuore Fondazione Policlinico Universitario A. Gemelli ‐ IRCCS Rome Italy
9. National Heart and Lung Institute Royal Brompton Hospital & Imperial College London London UK
10. Department of Ear‐Nose‐Throat Surgery General Hospital of Nafplio Nafplio Greece
11. General Practice Gezondheidscentrum Berkel en Rodenrijs Berkel en Rodenrijs The Netherlands
12. Asthma‐Allergiezentrum Leverkusen Leverkusen Germany
13. Department of Medicine School of Microbiology APC Microbiome Ireland National University of Ireland Cork Ireland
14. Department of Clinical and Experimental Sciences Respiratory Medicine Unit University of Brescia ASST Spedali Civili di Brescia Brescia Italy
15. Internal Medicine Department Durres Regional Hospital Durres Albania
16. Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Zürich Switzerland
17. Institute of Pathophysiology and Allergy Research Center of Pathophysiology Infectiology and Immunology Medical University of Vienna Vienna Austria
18. Department of Pediatrics Franciscus Gasthuis & Vlietland Rotterdam The Netherlands