Children’s hospitalisations due to COVID-19 were found to be higher than previously reported, although severe acute illness with COVID-19 remained rare in children, and the vast majority recovered quickly.

The nationwide study of more than 12 million health records of children and adolescents suggests that those from deprived backgrounds and from ethnic minorities were more likely to be hospitalised during the pandemic. Researchers say that the findings could inform public health policies for future outbreaks, including decisions around vaccinations.

Researchers led by University College London (UCL) and Great Ormond Street Hospital for Children NHS Foundation Trust (GOSH) on behalf of the BHF Data Science Centre COVID Consortium, analysed de-identified health records from July 2020 to February 2022. Data was accessed safely through NHS England’s Trusted Research Environment for England, a secure data platform for approved researchers.

Of just over 12 million children who live in England, 3.2 million had a first recorded infection with SARS-CoV-2 – the virus that causes COVID-19 – between July 2020 and February 2022.

Amongst these 3.2 million children and young people infected, just over 29000 (0.9%) were admitted to hospital. The study found that the reason for hospital admission was the virus itself, or the virus was a contributor, in the majority (just over 70%) of the children and adolescents who were admitted to hospital.

The types of hospital admission in these children and adolescents were 9875 (33.8%) caused by SARS-CoV-2 infection; 5330 (18.2%) suspected to be caused by SARS-CoV-2 infection; 4000 (13.7%) contributed to by SARS-CoV-2 infection; and 1790 (6.1%) due to PIMS -Ts – a serious multi-system inflammatory condition that can occur after a mild infection.

The remaining 7855 hospital stays (26.9%) were incidental to SARS-CoV-2 infection; and in a very small number, (just over 1%) the child or young person was infected with SARS-CoV-2 in hospital.

Almost half of the children and adolescents hospitalised had no known underlying medical condition. Boys, children under the age of 5 years, and those from ethnic minorities or areas of high deprivation, were more likely to end up in hospital.

Although most children and adolescents recovered quickly, as shown by the hospital stays of just a few days, 1,710 needed either high dependency or critical care. In the study period, 70 children died with COVID-19 listed as a contributor or a cause, and of these, 55 were deaths amongst the hospitalised children in the study.

The study is published in The BMJ and was supported by the BHF Data Science Centre at Health Data Research UK (HDR UK). It was funded by the Data and Connectivity National Core Study, led by HDR UK in partnership with the Office of National Statistics.

Senior author, Professor Katherine Brown, Consultant in Paediatric Cardiac Intensive Care at GOSH and Professor at the Institute of Cardiovascular Science at UCL, said: “We wanted to understand the extent of hospital admissions related to the virus SARS-CoV-2 in children and young people. After talking to parents and doctors, we included not only admissions due to COVID-19, but also admissions where the infection was strongly suspected as contributing to illness.

While these findings should not alarm parents, the study data are an indication that COVID-19 may have been more serious for some groups of children, especially those from ethnic minorities and deprived areas.”

The parent of a child who received critical care for COVID-linked paediatric inflammatory multi-system syndrome (PIMS-Ts), said: “It was reassuring as a parent to read about the vital research conducted. We are very grateful for research related to PIM- Ts and COVID-19 in children since this has enabled medical science to deliver life-saving health care.”

Read the paper here