TUESDAY, Oct. 7, 2025 (HealthDay News) -- Children and adolescents are twice as likely to experience long COVID after being infected for the second time, according to a study published online Sept. 30 in The Lancet Infectious Diseases.Bingyu Zhang, from the University of Pennsylvania in Philadelphia, and colleagues conducted a retrospective cohort study to assess the risk for post-acute sequelae of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection (PASC) diagnosis in children and adolescents after a SARS-CoV-2 reinfection during the omicron period. The analysis included patients younger than 21 years at enrollment in the Researching COVID to Enhance Recovery initiative, occurring in 40 U.S. children's hospitals and health institutions (465,717 children and adolescents with a first infection and 58,417 with a second infection from Jan. 1, 2022, to Oct. 13, 2023).The researchers found that the incident rate of PASC diagnosis was 903.7 per million people per six months in the first infection group and 1,883.7 in the second infection group. There was a significant association between reinfection and increased risk for an overall PASC diagnosis (relative risk [RR], 2.08) and a range of symptoms and conditions potentially related to PASC (RR range, 1.15 to 3.60), including myocarditis, changes in taste and smell, thrombophlebitis and thromboembolism, heart disease, acute kidney injury, fluid and electrolyte disturbance, generalized pain, arrhythmias, abnormal liver enzymes, chest pain, fatigue and malaise, headache, musculoskeletal pain, abdominal pain, mental ill health, postural orthostatic tachycardia syndrome or dysautonomia, cognitive impairment, skin conditions, fever and chills, respiratory signs and symptoms, and cardiovascular signs and symptoms."The results of this study further support one of the strongest reasons I give patients, families and physicians about getting vaccinated: More vaccines should lead to fewer infections, which should lead to less long COVID," coauthor Ravi Jhaveri, M.D., from the Northwestern University Feinberg School of Medicine in Chicago, said in a statement.One author disclosed ties to the pharmaceutical industry.Abstract/Full Text.Sign up for our weekly HealthDay newsletter