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Meta-Analysis
. 2021 Jan 22;39(4):667-677.
doi: 10.1016/j.vaccine.2020.11.078. Epub 2020 Dec 5.

Epidemiology of COVID-19 infection in young children under five years: A systematic review and meta-analysis

Mejbah Uddin Bhuiyan  1 , Eunice Stiboy  2 , Md Zakiul Hassan  3 , Mei Chan  4 , Md Saiful Islam  5 , Najmul Haider  6 , Adam Jaffe  7 , Nusrat Homaira  7
Affiliations
Meta-Analysis

Epidemiology of COVID-19 infection in young children under five years: A systematic review and meta-analysis

Mejbah Uddin Bhuiyan et al. Vaccine. .

Abstract

Introduction: Emerging evidence suggests young children are at greater risk of COVID-19 infection than initially predicted. However, a comprehensive understanding of epidemiology of COVID-19 infection in young children under five years, the most at-risk age-group for respiratory infections, remain unclear. We conducted a systematic review and meta-analysis of epidemiological and clinical characteristics of COVID-19 infection in children under five years.

Method: Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses , we searched several electronic databases (Pubmed, EMBASE, Web of Science, and Scopus) with no language restriction for published epidemiological studies and case-reports reporting laboratory-confirmed COVID-19 infection in children under five years until June 4, 2020. We assessed pooled prevalence for key demographics and clinical characteristics using Freeman-Tukey double arcsine random-effects model for studies except case-reports. We evaluated risk of bias separately for case-reports and other studies.

Results: We identified 1,964 articles, of which, 65 articles were eligible for systematic review that represented 1,214 children younger than five years with laboratory-confirmed COVID-19 infection. The pooled estimates showed that 50% young COVID-19 cases were infants (95% CI: 36% - 63%, 27 studies); 53% were male (95% CI: 41% - 65%, 24 studies); 43% were asymptomatic (95% CI: 15% - 73%, 9 studies) and 7% (95% CI: 0% - 30%, 5 studies) had severe disease that required intensive-care-unit admission. Of 139 newborns from COVID-19 infected mothers, five (3.6%) were COVID-19 positive. There was only one death recorded.

Discussion: This systematic review reports the largest number of children younger than five years with COVID-19 infection till date. Our meta-analysis shows nearly half of young COVID-19 cases were asymptomatic and half were infants, highlighting the need for ongoing surveillance to better understand the epidemiology, clinical pattern, and transmission of COVID-19 to develop effective preventive strategies against COVID-19 disease in young paediatric population.

Keywords: COVID-19; COVID-19 newborns; Children younger than five years.

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Conflict of interest statement

Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Fig. 1
Fig. 1
Flow diagram for study screening for the systematic review and meta-analysis
Fig. 2
Fig. 2
Risk of bias assessment for case-reports and case-studies included in the review
Fig. 3
Fig. 3
Risk of bias assessment for observational studies included in the review (excluding case-reports and case- studies)
Fig. 4
Fig. 4
Forest plot of proportion of all COVID-19 positive children (aged < 5 years) who were aged less than one year from 31 studies included in meta-analysis
See this image and copyright information in PMC

References

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