PT - JOURNAL ARTICLE AU - Luis García-Marcos AU - M. Innes Asher AU - Neil Pearce AU - Eamon Ellwood AU - Karen Bissell AU - Chen-Yuan Chiang AU - Asma El Sony AU - Philippa Ellwood AU - Guy B. Marks AU - Kevin Mortimer AU - A. Elena Martínez-Torres AU - Eva Morales AU - Virginia Perez-Fernandez AU - Steven Robertson AU - Charlotte E. Rutter AU - Richard J. Silverwood AU - David P. Strachan AU - The Global Asthma Network Phase I Study Group TI - The burden of asthma, hay fever and eczema in children in 25 countries: GAN Phase I study AID - 10.1183/13993003.02866-2021 DP - 2022 Jan 01 TA - European Respiratory Journal PG - 2102866 4099 - http://erj.ersjournals.com/content/early/2022/01/27/13993003.02866-2021.short 4100 - http://erj.ersjournals.com/content/early/2022/01/27/13993003.02866-2021.full AB - There have been no worldwide standardised surveys of prevalence and severity of asthma, rhinoconjunctivitis and eczema in school children for 15 years. The present study aims to provide this information.Following the exact International Study of Asthma and Allergies in Childhood (ISAAC) methodology (cross-sectional questionnaire-based survey) the Global Asthma Network (GAN) Phase I was carried out between 2015 and 2020 in many centres worldwide.The study included 157 784 adolescents (13–14 years of age) in 63 centres, in 25 countries; and 101 777 children (6–7 years of age) in 44 centres, in 16 countries. The current prevalence of symptoms, respectively, was: 11.0% and 9.1% for asthma; 13.3% and 7.7% for rhinoconjunctivitis; and 6.4% and 5.9% for eczema. For asthma ever, hay fever ever and eczema ever prevalence was 10.5% and 7.6%; 15.2% and 11.1%; and 10.6% and 13.4%. Centres in countries with low- or lower-middle- gross national income (LICs or L-MICs) had significantly lower prevalence of the three disease symptoms and diagnoses (except for hay fever). In children, the prevalence of asthma and rhinoconjunctivitis symptoms were higher in males, while the reverse occurred among adolescents. For eczema, while the prevalence among female adolescents was double that of males, there was no sex difference among children. Centre accounted for a non-negligible variability of all disease symptoms (10% to 20%).The burden of asthma, rhinoconjunctivitis and eczema vary widely among the limited number of countries studied. Although symptom prevalence is lower in LICs and L-MICs, it represents a considerable burden everywhere studied.FootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.Conflict of interest: Dr. Rutter declares UK Medical Research Council funding for PhD as part of MRCLID DTP with LSHTM and St Georges, grant number MR/N013638/1, in connection with the present manuscript.Conflict of interest: Dr. García-Marcos has nothing to disclose.Conflict of interest: Dr. Innes Asher has nothing to disclose.Conflict of interest: Dr. Pearce has nothing to disclose.Conflict of interest: Dr. Ellwood has nothing to disclose.Conflict of interest: Dr. Bissell has nothing to disclose.Conflict of interest: Dr. Chiang has nothing to disclose.Conflict of interest: Dr. El Sony has nothing to disclose.Conflict of interest: Dr. Ellwood has nothing to disclose.Conflict of interest: Dr. Marks has nothing to disclose.Conflict of interest: Dr. Mortimer has nothing to disclose.Conflict of interest: Dr. Martínez-Torres has nothing to disclose.Conflict of interest: Dr. Morales has nothing to disclose.Conflict of interest: Dr. Perez-Fernandez has nothing to disclose.Conflict of interest: Dr. Robertson has nothing to disclose.Conflict of interest: Dr. Silverwood has nothing to disclose.Conflict of interest: Dr. Strachan has nothing to disclose.