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.