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. 2023 Oct;34(10):e14037.
doi: 10.1111/pai.14037.

COVID-19 vaccine effectiveness in children by age groups. A population-based study in Galicia, Spain

Narmeen Mallah  1   2   3   4 , Jacobo Pardo-Seco  1   2   3 , Sonia Ares-Gómez  1   2   3 , Luis-Ricardo López-Pérez  5 , Juan-Manuel González-Pérez  5 , Benigno Rosón  5 , María-Teresa Otero-Barrós  6 , Carmen Durán-Parrondo  6 , Victoria Nartallo-Penas  6 , Susana Mirás-Carballal  6 , Carmen Rodríguez-Tenreiro-Sánchez  1   2   3 , Irene Rivero-Calle  1   2   3   7 , Alberto Gómez-Carballa  1   2   3 , Antonio Salas  1   2   3   8   9 , Federico Martinón-Torres  1   2   3   7
Affiliations

COVID-19 vaccine effectiveness in children by age groups. A population-based study in Galicia, Spain

Narmeen Mallah et al. Pediatr Allergy Immunol. 2023 Oct.

Abstract

Background: Studies on vaccine effectiveness (VE) against COVID-19 in the pediatric population are outgoing. We aimed to quantify VE against SARS-CoV-2 in two pediatric age groups, 5-11 and 12-17-year-old, while considering vaccine type, SARS-CoV-2 variant, and duration of protection.

Methods: A population-based test-negative control study was undertaken in Galicia, Spain. Children 5-11-year-old received the Comirnaty® (Pfizer, US) vaccine, while those aged 12-17-year-old received the Comirnaty® (Pfizer, US) or SpikeVax® (ModernaTX, Inc) vaccine. Participants were categorized into unvaccinated (0 doses or one dose with <14 days since vaccination), partially vaccinated (only one dose with ≥14 days, or two doses with <14 days after the second dose administration), and fully vaccinated (two doses with ≥14 days after the second injection). Adjusted odds ratios (OR) and their 95% confidence intervals (CI) were estimated using multiple logistic regression models. VE was calculated as (1-OR) * 100. Stratified and sensitivity analyses were performed.

Results: In the fully vaccinated 5-11-year-old children, VE against the Omicron variant was 44.1% (95% CI: 38.2%-49.4%). In the fully vaccinated 12-17-year-old individuals, VE was 83.4% (95% CI: 81.2%-85.3%) against Delta and 74.8% (95% CI: 58.5%-84.9%) against Omicron. Comirnaty® and SpikeVax® vaccines showed a similar magnitude of VE against Delta [Comirnaty® VE: 81.9% (95% CI: 79.3%-84.1%) and SpikeVax® VE: 85.3% (95% CI: 81.9%-88.1%)]. Comirnaty® (Pfizer, US; VE: 79.7%; 95% CI: 50.7%-92.4%) showed a slightly higher magnitude of protection against Omicron than SpikeVax® (ModernaTX, Inc), yet with an overlapping CI (VE: 74.3%; 95% CI: 56.6%-84.9%). VE was maintained in all age subgroups in both pediatric populations, but it declined over time.

Conclusions: In Galicia, mRNA VE was moderate against SARS-CoV-2 infections in the 5-11-year-old populations, but high in older children. VE declined over time, suggesting a potential need for booster dose schedules.

Keywords: COVID-19; Comirnaty® (Pfizer, US); Delta; Omicron; SARS-CoV-2; Spain; SpikeVax® (ModernaTX, Inc); mRNA vaccine; vaccine effectiveness.

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References

REFERENCES

    1. World Health Organization. WHO coronavirus (COVID-19) dashboard. 2023. https://covid19.who.int/. Accessed May 23, 2023.
    1. Spanish Ministry of Health. Informe n° 177. Situación de COVID-19 en España. [Report no. 177. COVID-19 situation in Spain]. 2023. https://www.sanidad.gob.es/profesionales/saludPublica/ccayes/alertasActu.... Accessed May 23, 2023.
    1. World Health Organization. Confirmed and probable COVID-19 cases by age. 2023. https://app.powerbi.com/view?r=eyJrIjoiYWRiZWVkNWUtNmM0Ni00MDAwLTljYWMtN.... Accessed May 23, 2023.
    1. World Health Organization. Interim statement on COVID-19 vaccination for children. 2022. https://www.who.int/news/item/11-08-2022-interim-statement-on-covid-19-v.... Accessed May 23, 2023.
    1. World Health Organization. COVID-19 disease in children and adolescents: scientific brief. 2021. https://www.who.int/publications/i/item/WHO-2019-nCoV-Sci_Brief-Children.... Accessed May 23, 2023.

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