Purpose
During fall 2021, children’s hospitals in Germany faced a surge in RSV-related
hospitalizations, whereas during fall/winter 2022–2023, RSV and
influenza infections both led to increased inpatient admissions. Our
study prospectively assessed severe acute respiratory infections, their
causative pathogens, and the resulting disease burden on German
children's hospitals for the fall/winter 2023–2024 season.

Methods
From October 3, 2023 through April 16, 2024, children hospitalized with ARI
as a primary diagnosis were monitored via a national survey established
by the German Society for Pediatric Infectious Diseases (DGPI). Weekly
data was collected on total hospital admissions, ARI-related admissions
by pathogen (SARS-CoV-2, RSV, influenza, other), ICU admissions with ARI
as a primary diagnosis, and respiratory support.

Results
Overall, 23% of German children's hospitals (77/334 centers) submitted 1234
survey reports. ARI-related hospital admissions surged starting in
November 2023 and peaked in late December 2023 (53.4% of all
admissions), in parallel with a peak in the average number of
newly-admitted patients (aNA) with RSV (2.5 aNA). In comparison to the
2022/2023 season, fewer newborns and infants were admitted for ARI
(4.7%, p < 0.001/1.9%, p = 0.05) and fewer required ICU treatment
(5.3%, p = 0.02/5.6%, p = 0.001 respectively). In 74.9% of ICU patients,
ventilation support was required—9.1% less than in the previous season.

Conclusion
The clinical burden on pediatric hospitals and ICUs is strongly influenced
by the changing, annually circulating pathogens and affected age group.
Therefore, a continuous, systematic, dynamic collection of ARI data is
critical for assessing the ARI-related morbidity and the associated
burden on health care systems.