Paediatric infection hospital admissions in England before, during and after the COVID-19 pandemic

The COVID-19 pandemic and associated non-pharmaceutical interventions (NPIs: containment measures/"lockdown") reduced transmission of other infections. We quantified changes in hospital admission rates for respiratory and gastrointestinal infections amongst young children in England during and after implementation of NPIs, compared to pre-pandemic, and variations by sociodemographic and clinical characteristics. Children aged <5 years at any time between 1 January 2017 and 31 January 2022 were followed from birth or 1 January 2017, until their 5th birthday, death or 31 January 2022, in a birth cohort based on Hospital Episode Statistics data. Quarterly emergency admission rates for respiratory and gastrointestinal infections from April-June 2020 onwards were compared to corresponding quarters in 2017-19 using Poisson regression models, with and without interaction terms for time period and sociodemographic/clinical characteristics. Admission rates for respiratory and gastrointestinal infections were lower in April-June 2020 compared to this quarter pre-pandemic (incidence rate ratio (99% CI) 0.17 (0.17-0.18) for respiratory; 0.29 (0.28-0.31) for gastrointestinal). Rates remained below pre-pandemic levels until April-June 2021 (respiratory infections) and July-September 2021 (gastrointestinal infections), subsequently increasing above the corresponding pre-pandemic quarters. Changes in rates did not differ by sociodemographic/clinical characteristics. These results can inform public health planning for future pandemics and their aftermath.