The vaccination of children against COVID-19, and whether those with underlying health conditions should be prioritised, was a major issue for policy-makers, clinicians and the public during the pandemic. The first known national population-level study of SARS-CoV-2 infections and COVID-19 hospitalisations among school age children (5-17 years old) with any of 13 underlying potentially high-risk conditions provided vital insights for policy makers to base decisions.

The challenge

When vaccines first became available, supply was limited so the question had to be addressed of who would benefit most. This initial dilemma was with adults, but the same issues existed for children. One key issue was whether certain groups of children were at higher risk of hospitalisation than others after being infected with SARS-CoV-2.

Addressing this would require a large-scale study that could rapidly provide information to decision-makers about hospitalisation rates among children and young people with a wide range of conditions.

The solution

The solution was a population-level study in Scotland which made use of the anonymised data of 752,867 5-17-year-olds held in the EAVE II linked dataset (which is supported by BREATHE, The HDR UK Hub for Respiratory Health). The research compared COVID-19 related hospitalisation rates among children with and without one of the following 13 risk groups: asthma, blood cancer, cerebral palsy, chronic kidney disease, congenital heart disease, type 1 diabetes, type 2 diabetes, epilepsy, learning disability, fracture, rare pulmonary diseases, severe mental illness, and sickle cell disease.

A paper entitled Risk of COVID-19 hospitalizations among school-aged children in Scotland: A national incident cohort study (published in the Journal of Global Health) details the research and its findings.


The research team found that the rate both of being tested and of COVID-19 hospitalisation was consistently higher within each risk group compared to those without the specific underlying conditions. It also identified that children with underlying health conditions are more likely to be admitted to hospital in general compared to those who did not have the specific health conditions.

Lead author, Dr Ting Shi who is a Chancellor’s Fellow in the University of Edinburgh’s Usher Institute, said:

“The research was important in identifying which underlying health conditions put children at increased risk of COVID-19 hospitalisation and who therefore should be potentially prioritised for COVID-19 vaccination.”

Among the risk groups where the hospitalisation rate related to COVID-19 was highest were those with sickle cell disease, chronic kidney disease, blood cancer and rare pulmonary diseases.

The research led to a follow-up study looking at the risks of COVID-19 hospitalisation in children with well-controlled and poorly-controlled asthma. This contributed directly to a decision by the Joint Committee on Vaccination and Immunisation (JCVI) to prioritise the vaccination of children with poorly controlled asthma.

What the impact committee said:

The committee commented on the high quality of the paper and data, and praised the research for addressing an understudied group, its high impact, international collaboration, data quality, PPIE and commitment to open science.

For further information contact shi@ed.ac.uk.