Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Methodol. Jan 20, 2021; 11(1): 1-14
Published online Jan 20, 2021. doi: 10.5662/wjm.v11.i1.1
Epidemiological burden of parents being the index cases of COVID-19 infected children
Sumanta Saha, Sujata Saha
Sumanta Saha, National Institute of Epidemiology, Ayapakkam, Chennai, Tamil Nadu 600077, India
Sujata Saha, Department of Mathematics, Mankar College, Mankar 713144, India
Author contributions: Sumanta Saha prepared the concept and design, performed the data analysis, and drafted the manuscript; Sujata Saha hard edited the manuscript; both authors contributed to the study selection and risk of bias assessment and agree with the content of the final version of the manuscript.
Conflict-of-interest statement: The authors do not have any conflict of interest to declare.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Sumanta Saha, MPH, DNB, MBBS, Doctor, National Institute of Epidemiology, Ayapakkam, Chennai, Tamil Nadu 600077, India.
Received: December 3, 2020
Peer-review started: December 3, 2020
First decision: December 11, 2020
Revised: December 17, 2020
Accepted: December 27, 2020
Article in press: December 27, 2020
Published online: January 20, 2021

In the ongoing coronavirus disease 2019 (COVID-19) pandemic, when children remain home-confined secondary to the closure of schools, little is known of the burden of the parents being their index case.


To determine the prevalence of parents being the index case of COVID-19 infected children.


A database search in PubMed and Scopus ensued to recruit studies reporting the index case information of COVID-19 infected individuals aged ≤ 18. The reviewed articles' quality evaluation included the use of the National Heart, Lung, and Blood Institute's tool. A random-effect meta-analysis ensued to determine the prevalence of the parent being and not-being the index case. Heterogeneity was assessed by I2 and Chi2 statistics. The publication bias was evaluated by funnel plots and Egger’s test.


Overall, this review included 13 eligible studies sourcing data from 622 children of 33 nations. Study designs were heterogeneous and primarily included descriptive reports (38.4%). The prevalence of parent being the index case was 54% (95%CI: 0.29-0.79; I2: 62.3%, Chi2 P < 0.001). In > 70% of children, their index-case parent was symptomatic due to COVID-19 at the time of infection transmitting. Studies for which a risk of bias assessment was possible were of fair quality.


There is a substantial global burden of parents being the index case of COVID-19 infected children, and frequently these parents are symptomatic. Therefore, from a public health perspective, early detection of these parents is crucial.

Keywords: COVID-19 pandemic, COVID-19, Index case epidemiology, Patient zero epidemiology, Pediatrics

Core Tip: During the ongoing coronavirus disease 2019 (COVID-19) pandemic situation, while schools remain closed and children primarily stay at home, the prevalence of parent to child COVID-19 transmissibility remains unknown. Therefore, this meta-analysis chiefly quantifies this epidemiological burden. Globally, this burden was substantial (about 54%) and was highest in Asia. The majority of these parents (> 70%) were symptomatic. This study highlights the public health importance of early detection of COVID-19 infected parent index cases to decrease transmission to their wards.