Long COVID in Children and Adolescents: Mechanisms, Symptoms, and Long-Term Impact on Health-A Comprehensive Review

Long COVID, also known as post-acute sequelae of SARS-CoV-2 infection (PASC), is increasingly recognized as a condition affecting not only adults but also children and adolescents. While children often experience milder acute COVID-19 symptoms compared to adults, some develop persistent physical, psychological, and neurological symptoms lasting for weeks or months after initial infection. The most commonly reported symptoms include debilitating fatigue, respiratory issues, headaches, muscle pain, gastrointestinal disturbances, and cognitive difficulties, which significantly impact daily activities, schooling, and social interactions. Additionally, many children with long COVID experience psychological symptoms, such as anxiety, depression, mood swings, and irritability, likely exacerbated by prolonged illness and lifestyle disruptions. Risk factors for long COVID in children include pre-existing health conditions such as asthma, obesity, and neurological disorders, with adolescents and females seemingly more affected. Hypothesized mechanisms underlying long COVID include chronic immune dysregulation, persistent viral particles stimulating inflammation, autonomic nervous system dysfunction, and mitochondrial impairment, which may collectively contribute to the variety of observed symptoms. Long-term outcomes remain uncertain; however, long COVID can lead to school absenteeism, social withdrawal, and psychological distress, potentially affecting cognitive development. Severe cases may develop chronic conditions such as postural orthostatic tachycardia syndrome (POTS) and reduced exercise tolerance. This review synthesizes the existing literature on long COVID in children, examining its prevalence, symptomatology, risk factors, and potential mechanisms, with an emphasis on the need for further clinical studies. While existing research largely relies on surveys and self-reported data, clinical assessments are essential to accurately characterize long COVID in pediatric populations and to guide effective management strategies.