1 Vol.:(0123456789) Scientific Reports | (2024) 14:47 | https://doi.org/10.1038/s41598-023-49210-1 www.nature.com/scientificreports Epidemiology of 7375 children and adolescents hospitalized with COVID‑19 in Germany, reported via a prospective, nationwide surveillance study in 2020–2022 Maren Doenhardt 1,205* , Markus Hufnagel 2,205 , Natalie Diffloth 1 , Johannes Hübner 3 , René Mauer 4 , Dominik T. Schneider 5 , Arne Simon 6 , Tobias Tenenbaum 7 , Andreas Trotter 8 , Jakob Armann 1 , Reinhard Berner 1 & The DGPI COVID‑19 working group * By means of a nationwide, prospective, multicenter, observational cohort registry collecting data on 7375 patients with laboratory‑confirmed SARS‑CoV‑2 admitted to children’s hospitals in Germany, March 2020–November 2022, our study assessed the clinical features of children and adolescents hospitalized due to SARS‑CoV‑2, evaluated which of these patients might be at highest risk for severe COVID‑19, and identified underlying risk factors. Outcomes tracked included: symptomatic infection, case fatality, sequelae at discharge and severe disease. Among reported cases, median age was one year, with 42% being infants. Half were admitted for reasons other than SARS‑CoV‑2. In 27%, preexisting comorbidities were present, most frequently obesity, neurological/neuromuscular disorders, premature birth, and respiratory, cardiovascular or gastrointestinal diseases. 3.0% of cases were admitted to ICU, but ICU admission rates varied as different SARS‑CoV‑2 variants gained prevalence. Main risk factors linked to ICU admission due to COVID‑19 were: patient age (> 12 and 1–4 years old), obesity, neurological/neuromuscular diseases, Trisomy 21 or other genetic syndromes, and coinfections at time of hospitalization. With Omicron, the group at highest risk shifted to 1–4‑year‑olds. For both health care providers and the general public, understanding risk factors for severe disease is critical to informing decisions about risk‑reduction measures, including vaccination and masking guidelines. Abbreviations CI Confidence interval COVID-19 Coronavirus disease 2019 CPAP Continuous positive airway pressure OPEN 1 Department of Pediatrics, University Hospital and Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany. 2 Division of Pediatric Infectious Diseases and Rheumatology, Department of Pediatrics and Adolescent Medicine, University Medical Center, Medical Faculty, University of Freiburg, Freiburg, Germany. 3 Division of Pediatric Infectious Diseases, Hauner Children’s Hospital, Ludwig-Maximilians- Universität München, Munich, Germany. 4 Institute for Medical Informatics and Biometry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany. 5 Clinic of Pediatrics, Municipal Hospital Dortmund, University Witten, Herdecke, Germany. 6 Pediatric Oncology and Hematology, Children’s Hospital Medical Center, University Clinics, Saarland, Germany. 7 Clinic for Child and Adolescent Medicine, Sana Klinikum Lichtenberg, Academic Teaching Hospital, Charité-Universitätsmedizin Berlin, Berlin, Germany. 8 Children’s Hospital and Center for Perinatal Medicine, Teaching Hospital of the University of Freiburg, Singen, Germany. 205 These authors contributed equally: Maren Doenhardt and Markus Hufnagel. * A list of authors and their affiliations appears at the end of the paper. * email: maren.doenhardt@tu-dresden.de