Peer-reviewed article
Long COVID in children in Australia and the potential impact of vaccination.
Valentina Costantino, Adriana Notaras, Chandini Raina MacIntyre ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study estimates the burden of Long COVID in Australian children aged 6 months to 11 years during 2021-2023 using seroprevalence data and modelling. The youngest children (6 months-4 years) had higher rates of Long COVID symptoms (0.8%) compared to older children (0.3%), though older children had higher infection rates. Vaccination could reduce Long COVID prevalence, but the actual impact depends heavily on vaccine coverage levels and whether vaccine effectiveness wanes over time.
Key points
- By end of 2022, seroprevalence was 85.6% in children aged 5-11 years and 77.9% in children aged 6 months-4 years
- Approximately 0.8% of the youngest children experienced Long COVID compared with 0.3% of children aged 5-11 years
- Actual vaccination coverage of 40% in the 5-11 age group averted only 9% of infections and reduced Long COVID prevalence by 13%
- If coverage reached 94% (comparable to adults aged 70+), infections could be reduced by 32-55% and Long COVID prevalence by 34%
- Assuming vaccine effectiveness waning of 12% per month, reductions in Long COVID prevalence would be limited to 2-4% regardless of coverage
Limitations
This is a modelling study based on assumptions about vaccine effectiveness and coverage scenarios rather than direct measurement of vaccination outcomes in children. The findings are sensitive to assumptions about vaccine effectiveness waning, and real-world effectiveness may differ from the scenarios tested.
Abstract
Long COVID (LC) or Post-COVID condition (PCC) is a serious illness that can result in chronic conditions in all ages, including children. We used SARS-CoV-2 infection-induced data to find monthly seroprevalence in 6 months to 11 year olds in 2021-2022 to estimate the proportion experiencing PCC. A non-dynamic model using age-specific PCC rates, in accordance with the WHO definition of LC and the National Academies of Sciences, Engineering, and Medicine (NASEM) definition of PCC, was applied to estimate the burden of LC in children during 2021-2023 and to evaluate the impact of vaccination under different coverage and vaccine effectiveness (VE) scenarios. By the end of 2022, seroprevalence was higher among children aged 5-11 years (85.6%) than among those aged 6 months-4 years (77.9%). However, a higher proportion of the youngest age experienced LC (approximately 0.8%), compared with children aged 5-11 year (approximately 0.3%). The low vaccination coverage achieved in the 5-11 age group (40%) averted approximately 9% of infections and reduced LC prevalence by 13% at the end of 2022 under the assumption of no waning VE. If children aged 6 months-4 years age group, who were ineligible for routine vaccination, had been vaccinated at the same uptake level, infections and LC prevalence could have been reduced by approximately 5% and 10%, respectively. Achieving coverage comparable to that of adults aged 70 years and older (94%) would have resulted in substantially larger reductions in infections (∼ 32%-55%) and LC prevalence (∼34%) in both paediatric age groups. However, assuming VE waning 12% per month, the reduction in seroprevalence and LC prevalence are limited to 2-4%, depending on coverage. These findings suggest that vaccination can reduce LC burden in children, which should be considered in vaccine policy.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
Problem
Long COVID (chronic post-COVID condition) in children, which affects development and wellbeing
- Intervention
- SARS-CoV-2 vaccination at different coverage levels and with varying assumptions about vaccine effectiveness waning
- Population
- Australian children aged 6 months to 11 years
Key finding
At actual 40% vaccination coverage in 5-11 age group, Long COVID prevalence reduced by 13%