November 2025
Risk of long COVID in children doubles after second infection, finds study
By Melanie Hinze
New research, published in The Lancet Infectious Diseases, suggests the risk of long COVID in children might be twice as high in those who are infected with SARS-CoV-2 for a second time.
The retrospective cohort study used data from electronic health records of more than 460,000 children and adolescents from 40 paediatric hospitals across the USA from January 2022 to October 2023 – a period that was dominated by the Omicron variant.
All participants had documented SARS-CoV-2 infection, the mean age was 8.17 years, 50.2% were male and almost 60,000 children (12.5%) were identified as having a second infection episode.
The incidence of post-acute sequelae of SARS-CoV-2 infection (PASC) was 903.7 per million people per six months in the first infection group compared with 1883.7 per million people per six months in the group who had a second infection.
The researchers found that reinfection was not only associated with a significantly increased risk of PASC diagnosis (relative risk, 2.08), but also with conditions potentially related to PASC. These included myocarditis, changes in taste and smell, thrombophlebitis and thromboembolism, heart disease, acute kidney injury, chest pain, fatigue and malaise, headache, postural orthostatic tachycardia syndrome or dyskjautonomia, cognitive impairment, skin conditions, and respiratory and cardiovascular symptoms.
The increased risk was seen across many different groups, regardless of their vaccination status, severity of first illness, age, gender, race or ethnicity, or if they were living with overweight or obesity.
‘These findings emphasise the ongoing risk of PASC with reinfection, regardless of severity, and suggest that the risk of PASC might be cumulative with each successive infection,’ the researchers wrote.
Professor Peter Sly, Director of the Children’s Health and Environment Program, NHMRC Leadership Fellow and Emeritus Paediatric Respiratory Physician at the University of Queensland, Brisbane, said that the main message from this research was to make sure that children kept up with their recommended vaccinations.
‘We’ve seen all over Australia this year, real drop-offs in vaccination rates and increases in [infectious diseases such as] flu and measles that are purely related to a lack of vaccination,’ he said.
Professor Sly told Medicine Today that these other viral infections were a much bigger threat to our children in Australia than COVID-19.
‘However, this article highlights that if a child has had one COVID infection, they’re more likely to get long COVID syndrome if they go on to have a second COVID infection’, he added.
Professor Sly recommended that clinicians follow the current guidelines, which at present do not recommend COVID-19 vaccination for healthy infants, children or adolescents. However, primary vaccine doses are recommended for infants, children and adolescents with medical conditions that increase the risk of severe COVID-19 illness, and for those who are severely immunocompromised.