Children and young people have less severe covid-19 than adults and death is exceptionally rare, only occurring in children with serious underlying conditions, confirms a study published by The BMJ today.
However, the findings also show that children of Black ethnicity were disproportionately severely affected by covid-19 infection.
Children and young people make up only 1-2% of cases of covid-19 worldwide, and the vast majority of reported infections in children are mild or asymptomatic, with few recorded deaths.
As such, there has been less information on ethnicity, underlying conditions (comorbidities), and outcomes for children with covid-19 than in adults.
To address this knowledge gap, UK researchers in the ISARIC4C consortium analysed data from 651 children and young people (aged less than 19 years) with covid-19 admitted to 138 hospitals in England, Wales, and Scotland between 17 January and 3 July 2020.
The median age of patients in the study was 4.6 years, predominantly male (56%) and of white ethnicity (57%), with most (58%) children having no known comorbidities.
The main outcome measures were admission to critical care (a high dependency unit or intensive care unit), death in hospital, or meeting the World Health Organization definition for multisystem inflammatory syndrome (MIS-C) - a rare condition thought to be linked to covid-19.
Patients were tracked for a minimum of two weeks (to 17 July 2020), during which time 18% (116) children were admitted to critical care. Those aged younger than 1 month, aged 10-14 years, and of black ethnicity were more likely to be admitted to critical care.
Six children (1%) died in hospital, all of whom had profound comorbidity. This is a "strikingly low" fatality rate compared with 27% across all ages (0-106 years) over the same time period, note the authors.
Eleven percent of children met the WHO definition for MIS-C. These children were older (average age 10.7 years) and more likely to be of non-white ethnicity.
These children were also more likely to be admitted to critical care, show symptoms such as fatigue, headache, muscle pain and sore throat, and have a low blood platelet count, but there were no deaths in this group.
This is an observational study, so can't establish cause, and the researchers point to some limitations that may have affected their results.
However, they say this large study not only gives a detailed picture of the clinical characteristics, risk factors, and outcomes of covid-19 in children, it should also help to refine the WHO criteria for multisystem inflammatory syndrome.
As such, they conclude that severe disease is rare and death is exceptionally rare in children admitted to hospital with covid-19, but that ethnicity seems to be a risk factor for more severe illness.
Peer reviewed? Yes
Evidence type: Observational
Subjects: Children admitted to UK hospitals with covid-19