COVID-19 produced more symptoms and complications than seasonal influenza in children, while death was rare among them, revealed a large new study.

Early in the pandemic, opinions around the impact of COVID-19 on children and adolescents ranged from it being no more than the common flu to fear of its potential impact on lesser-developed immune systems. To understand, researchers from IDIAP Jordi Gol in Barcelona compared the real-world observational data of more than 242,000 children and adolescents diagnosed with COVID-19, including nearly 10,000 hospitalised youths, to more than 2,000,000 diagnosed with influenza across five countries (France, Germany, South Korea, Spain, and the US) to provide a clearer picture of COVID's impact.

The study, published online in the journal Pediatrics, showed that asthma and obesity were the most common comorbidities. There was also a higher prevalence of rare conditions, including congenital malformations, neurodevelopmental disorders, and heart disease, among those hospitalised with COVID-19. Paediatric patients with COVID-19 also showed higher rates of symptoms such as laboured breathing, loss of smell and gastrointestinal symptoms than those with influenza.

The most common 30-day complications for hospitalised youths with COVID-19 were hypoxemia and pneumonia, both of which occurred at a higher rate than hospitalised influenza paediatric patients. "This study addressed critical questions that were weighing down on both the healthcare community and the general population how was COVID-19 impacting our youngest population", said study lead Talita Duarte-Salles, an epidemiologist at IDIAP Jordi Gol in Barcelona.

"While some last year claimed that COVID-19 was no different than the flu, the real-world evidence we generated through open science showed something quite different. It was a relief to see that fatality was rare, but clearly, both complications and symptoms showed the COVID-19 was no flu in children and adolescents", Duarte-Salles added.