A team from King’s College London (KCL) has found that fewer than one in 20 children with symptomatic COVID-19 experienced symptoms lasting longer than four weeks. Nearly all children have fully recovered by eight weeks.

The new study, published in Lancet Child and Adolescent Health, saw researchers at KCL look at daily health reports logged in the ZOE COVID Symptom Study app between March 2020 and February 2021 by parents or carers on behalf of more than 250,000 children aged 5-17.

1,734 children were found to have a clear start and end point to their symptoms and a positive COVID-19 PCR test, enabling the researchers to determine their duration of illness with some allowance for symptoms reoccurring.

On average, the illness lasted for five days in younger children (five to 11 years old) and seven days in older children aged 12 to 17. Fewer than one in 20 (4.4%) experienced symptoms for four weeks or more, while only one in fifty (1.8%) had symptoms lasting more than eight weeks.

The team previously analysed data from adults using the ZOE COVID Symptom Study, showing that around one in seven adults experienced COVID-19 symptoms lasting four weeks, while one in 20 were ill for eight weeks or longer.

“We know from other studies that many children who catch coronavirus don’t show any symptoms at all; and it will be reassuring for families to know that those children who do fall ill with COVID-19 are unlikely to suffer prolonged effects,”said senior author Emma Duncan, professor of clinical endocrinology from KCL’s School of Life Course Sciences.

"However, our research confirms that a small number do have a long illness duration with COVID-19, though these children too usually recover with time,” she added.