Before January 22, 2020, only one pediatric case of COVID-19 was reported in mainland China1,2. However, a retrospective surveillance study3 identified six children who had been hospitalized for COVID-19 in one of three central Wuhan hospitals between January 7th and January 15th. Given that Wuhan has over 395 other hospitals, there may have been far more severe pediatric cases than reported.
There were six and 43 children out of 336 who tested positive for COVID-19 and influenza, respectively among all pediatric admissions during the 9-day period3. By using this ratio in a detailed analysis of influenza surveillance data and COVID-19 epidemic dynamics (see Appendix), we estimate that there were 313 [95% CI: 171-520] children hospitalized for COVID-19 in Wuhan during January 7-15, 2020 (Figure). Under an epidemic doubling time of 7.31 days4, we estimate that there were 1105 [95% CI: 592, 1829] cumulative pediatric COVID-19 hospitalizations prior to the January 23rd lockdown, which far surpasses the 425 confirmed cases reported across all age groups, none of which were children under age 151.
Figure. Estimated COVID-19 pediatric hospitalizations (under age 17) in the 13 districts of Wuhan from January 7 to January 15, 2020.
A retrospective study identified five hospitalized pediatric cases of COVID-19 from four central districts of Wuhan3 and one from the neighboring Huanshi district3. We estimate that there were a total of 313 [95% CI: 171-520] severe (hospitalized) cases of COVID-19 in children during that nine-day period across the 13 central districts of Wuhan. Across districts our estimates range from four [95% CI: 0-9] in suburban Hannan to 38 [95% CI: 19-68] in central Hongshan as indicated by shading (Table S1).
Children are strikingly absent from COVID-19 reports and limited data suggest that pediatric infections are overwhelmingly mild5. Thus, our estimates for hundreds of severe pediatric cases likely translates to thousands or even tens of thousands of mildly infected children, suggesting that the force of infection from children may be grossly underestimated and the infection fatality rate overestimated from confirmed case counts alone. This highlights the urgent need for more robust surveillance to gauge the true extent and severity of COVID-19 in all ages.
Supplementary Material
Acknowledgments
We acknowledge grant support from NIH (U01 GM087719).
Role of the funding source
The funders had no role in the design, analysis, write-up or decision to submit for publication.
Footnotes
Declaration of interests
We declare no competing interests.
Ethics committee approval
Not applicable.
References
- 1.Li Q, Guan X, Wu P, et al. Early Transmission Dynamics in Wuhan, China, of Novel Coronavirus-Infected Pneumonia. NEngl JMed 2020; published online Jan 29. DOI: 10.1056/NEJMoa2001316 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Chan JF- W, Yuan S, Kok K- H, et al. A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster. Lancet 2020; 395: 514–23. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Liu W, Zhang Q, Chen J, et al. Detection of Covid-19 in Children in Early January 2020 in Wuhan, China. N Engl J Med 2020; published online March 12. DOI: 10.1056/NEJMc2003717 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Du Zhanwei, Wang Lin, Cauchemez Simon, et al. Risk for Transportation of 2019 Novel Coronavirus Disease from Wuhan to Other Cities in China. Emerging Infectious Disease journal 2020; 26 DOI: 10.3201/eid2605.200146 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Tang A, Xu W, Shen M, et al. A retrospective study of the clinical characteristics of COVID-19 infection in 26 children. Infectious Diseases (except HIV/AIDS). 2020; published online March 10. DOI: 10.1101/2020.03.08.20029710 [DOI] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.