J Korean Med Sci.  2022 May;37(17):e124. 10.3346/jkms.2022.37.e124.

Short Term Impact of Coronavirus Disease 2019 Vaccination in Children in Korea

• Lee H
• Choi EH
• Park YJ
• Choe YJ

• KMID: 2529700
• DOI: http://doi.org/10.3346/jkms.2022.37.e124

Abstract

Background
The epidemiology of coronavirus disease 2019 (COVID-19) has changed continuously throughout the pandemic.
Methods
We analyzed changes in the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection according to the age group in South Korea from February 2020 to December 2021.
Results
Since the COVID-19 pandemic, the incidence among adults aged ≥ 18 years was higher than all the other age groups in 2020; however, a shift toward younger ages occurred in June 2021. In addition, we found significant changes in epidemiology after the introduction of SARS-CoV-2 vaccines in adults aged ≥ 18 and children 12–17 years. Until recently, children were not regarded as the drive for the pandemic; however, children aged 5–11 and 0–4 years had the highest incidence among all the age groups.
Conclusion
Therefore, policies for clinical support for an increase in COVID-19 cases among young children and age-specific preventive measures are needed.

Keyword

COVID-19; Child; Adolescent; Korea; Vaccine

Figure

• 

  Fig. 1 Timeline of confirmed COVID-19 incidences by (A) age-specific weekly incidence, and (B) monthly age-adjusted incidence rate ratio in children by age group, in comparison to adults, South Korea January 2020–December 2021.COVID-19 = coronavirus disease 2019, SARS-CoV-2 = severe acute respiratory syndrome coronavirus 2.aThe 7-day moving average of new cases (current day + 6 preceding days/7) was calculated to smooth the expected variation in daily case counts.

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