Epidemiology of 7375 children and adolescents hospitalized with COVID-19 in Germany, reported via a prospective, nationwide surveillance study in 2020-2022

Abstract

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.

Figure 1

(A) Pediatric hospitals in Germany submitting cases of patients hospitalized with COVID-19 to the registry, January 1, 2020–November 30, 2022 (n = 198; DGPI COVID-19 working group). (B) Pediatric cases on general wards and intensive care units, as reported to the COVID-19 Survey, January 1, 2020–November 30, 2022. The relative predominance of different SARS-CoV-2 variants of concern (VOC) in Germany since the beginning of the COVID-19 pandemic has been determined according to VOC data provided by the Robert Koch-Institute (RKI). According to calendar week (CW), these phases were: Wildtype (CW 1, 2020–CW 8, 2021); Alpha VOC (CW 9–24, 2021); Delta VOC (CW 25–51, 2021; Omicron BA.1 VOC (CW 52, 2021–CW 8, 2022); Omicron BA.2 VOC (CW 9–22, 2022); and Omicron BA.4/BA.5 VOC (CW 23–48, 2022).

Figure 2

(A) Distribution of SARS-CoV-2 variants according to patient age. Pediatric cases reported from January 1, 2020–November 30, 2022. The relative predominance of different SARS-CoV-2 variants of concern (VOC) in Germany since the beginning of the COVID-19 pandemic has been determined according to VOC data provided by the Robert Koch-Institute (RKI). (B) Diagnosis of syndromic conditions among pediatric COVID-19 patients by age. Pediatric cases reported from January 1, 2020–November 30, 2022. *Upper respiratory tract infections included ear, nose and throat infections, as well as pseudocroup. **Lower respiratory tract infections included bronchitis/bronchiolitis, pneumonia and Pediatric Acute Respiratory Syndrome (pARDS).

Figure 3

(A) Therapy provided in connection with infection from different SARS-CoV-2 variants. Pediatric cases reported from January 1, 2020–November 30, 2022. The relative predominance of different SARS-CoV-2 variants of concern (VOC) in Germany since the beginning of the COVID-19 pandemic has been determined according to VOC data provided by the Robert Koch-Institute (RKI). (B) COVID-19 therapy provided, by age group. Pediatric cases reported from January 1, 2020–November 30, 2022.

Figure 4

Risk factors for ICU admission; Comparison of three subsets: all patients (CW 1, 2020 to CW 48, 2022), pre-Omicron (CW 1, 2020 to CW 51, 2021) and Omicron (CW 52, 2021 to CW 48, 2022). Only symptomatic patients were included (N = 6512 out of 7375 total). To test a two-sided hypothesis, variables were analyzed in a fully-adjusted Poisson regression model with a 95% confidence interval (CI) and significance level of 0.05.