Background: Long COVID remains incompletely understood in children and adolescents with scant Australian data available. We aimed to assess the impacts of the 2021 Delta variant of SARS-CoV-2 outbreak on symptoms and functioning 12 weeks post-acute infection in a cohort of children and adolescents. Methods: The parents (or next of kin) of 11864 children and adolescents from a population catchment who had mandatory contact with Sydney Childrens Hospital Network facilities during acute SARS-CoV-2 infection (confirmed by PCR) were contacted by email or text message. Findings: 1731 (17.7%) responded to an online survey assessing symptoms, functional impairment. 203 of the responders (11.7%) gave answers that were consistent with continued symptoms and/or functional impairment and were flagged for clinical review. Of the 169 subsequently clinically reviewed, many had already recovered (n=63, 37.3%) or had a pre-existing condition exacerbated by COVID-19 (18, 10.7%); 64 (37.9%) were diagnosed with a Post COVID Condition (PCC). Of these, a minority we considered to have features compatible with the United Kingdom consensus cases definition for Long COVID (n=21). Interpretation: During an outbreak of the Delta variant of SARS-CoV-2 an online questionnaire with subsequent clinical review revealed self-reported non-recovery at 12 weeks in a minority of cases, with a spectrum of features. Long COVID comprised only a subset of cases with self-reported non-recover, is infrequent in children and adolescents, but still comprises a likely significant burden that warrants attention.

The authors have declared no competing interest.

New South Wales Health COVID-19 Emergency Response Priority Research Funding

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The study received ethical approval from the Sydney Local health District (Royal Prince Alfred Hospital Zone) Human Research Ethics Committee (HREC ID: 2021/ETH11819 & X21-0370).

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All data produced in the present study are available upon reasonable request to the authors