Abstract
BACKGROUND: Long COVID describes the persistence or recurrence of symptoms beyond the acute phase of SARS-CoV-2 infection and is increasingly recognized in children and adolescents. Despite its prevalence, understanding of symptom patterns and the influence of vaccination on disease trajectory in pediatric populations remains limited. METHODS: We conducted a retrospective study of patients aged 0-21 years evaluated at the Long COVID Clinic at Children's Hospital Los Angeles between August 2021 and November 2023. Patients were included if they reported persistent or new symptoms ≥4 weeks after SARS-CoV-2 infection. RESULTS: A total of 123 patients were enrolled. The mean age was 13.1 years, and 51% were male. Symptom onset occurred a mean of 5 weeks after infection. At presentation, 56% of patients reported symptoms lasting 0-24 weeks, 28% for 25-52 weeks, and 16% for >52 weeks. Fatigue (93%) and headache (70%) were the most prevalent symptoms in both younger (<12 years) and older (>12 years) cohorts. Female patients more frequently reported brain fog, dizziness, palpitations, and postural orthostatic tachycardia syndrome. Overall symptom burden decreased significantly over time (p < 0.001). Vaccination status at baseline was not associated with difference in symptom duration on initial presentation (p = 0.4). However, among those vaccinated after developing long COVID, 41% reported subjective improvement in the following weeks. CONCLUSION: Pediatric long COVID is marked by prolonged, multisystem symptoms. Vaccination may offer symptomatic benefit for some patients, though larger prospective studies are necessary to better define its role.