A year-long study led by Southampton researchers has shown children with a weakened immune system are not more likely to become seriously ill with COVID-19.
The ImmunoCOVID19 study, led by Dr Hans de Graaf, sent weekly COVID-19 questionnaires to ‘immunocompromised’ children or their parents between March 2020 and March 2021.
The children all had a weakened immune system, either due to a health condition or the medication they were taking, such as chemotherapy drugs to treat cancer.
The results, published in The Journal of Infection, found these children are not at greater risk of severe disease after catching COVID-19 compared to children in the general UK population.
In total 1,527 families from 46 hospitals took part, completing a weekly online survey that included questions on COVID-19 symptoms and PCR test results.
No COVID-19 cases were reported until September 2020. A total of 38 children had positive PCR test results between then and March 2021. Four of these children were hospitalised, but did not require intensive care, and none of the children died.
Those who tested positive tended to be older, with symptoms of a fever, cough, and sore throat. This matched the national trend for children who are not immunocompromised.
Signs of COVID-19 immunity
In the last two months, the researchers also looked for the presence of antibodies to COVID-19 – a sign of developing immunity to the disease – in the blood of 452 unvaccinated children.
People who are immunocompromised are less likely to have COVID-19 antibodies after infection, meaning their body’s immune system is unprepared the next time it encounters the virus.
Of the 18 children who had a positive COVID-19 test result, half were found to have antibodies. They also detected antibodies in 7.4% of children with no record of having had COVID-19.
Dr Hans de Graaf, consultant in paediatric rheumatology and clinical research fellow at University Hospital Southampton, said: “These results provide some much-needed reassurance for immunocompromised children and their parents, who we found experienced high levels of anxiety in relation to COVID-19.
“I hope our study gives them the evidence they sought, and they can take comfort from our finding that they are at no higher risk than any other child in the UK.”
This research was led by researchers at the NIHR Southampton Clinical Research Facility and NIHR Southampton Biomedical Research Centre, with contributions from researchers at the University of Nottingham and Wolfson Centre for Global Virus Research.