Background: Few paediatric cases of COVID-19 have been reported and we know little about the epidemiology in children. We have synthesised what is known globally about SARS-CoV-2 in children, including infection rate, clinical presentation, clinical outcomes and transmission dynamics. We discuss in the context of data relating to two other novel coronaviruses (SARS-CoV and MERS-CoV) in paediatric populations that were also reviewed. We aim to inform clinical and public health measures relating to children affected by the COVID-19 pandemic. Methods: We undertook a rapid systematic review and narrative synthesis of all literature relating to SARs-CoV-2 in paediatric populations. The search terms also included SARS-CoV and MERS-CoV, to inform the discussion. We searched three databases and hand searched the COVID-19 resource centres of eleven major journals and publishers for all studies addressing the research questions. English abstracts of Chinese language papers were included. Data were extracted and narrative syntheses conducted. Findings: 24 studies relating to COVID-19 were included in the review. The quality of the literature is generally poor, and the majority is from China. Children appear to be less affected by the COVID-19 outbreak than adults by observed rate of cases in large epidemiological studies. Limited data on attack rate indicate that children are just as susceptible to infection. Data on clinical outcomes are scarce but include several reports of asymptomatic infection and a milder course of disease in young children. Radiological abnormalities are noted in both groups. Severe cases are not reported in detail and there has been one reported death. There is one reported case of transmission from a child to an adult and no further data relating to transmission from children. Interpretation: There is an emerging discrepancy between observed case rate of COVID-19 (lower) and infection rate of SARS-CoV-2 (higher) in children in China. Children may be asymptomatic or too mildly infected to draw medical attention, be tested and counted in observed cases of COVID-19. Household configuration in China (as a legacy of the ‘one-child’ policy) may mean the Chinese experience of paediatric case rates will not prove to be typical. There are inadequate data on transmissibility of SARS-CoV-2 from children. To our knowledge this is the most comprehensive review of evidence on paediatric COVID-19 to date. It highlights gaps in knowledge that demonstrate the importance of evidence generation in paediatric populations, equivalent to that in adults, as part of the current pandemic response. Funding Statement: Oliver Mytton’s salary is funded through an NIHR Academic Clinical Lecturer award. Edward Mullin’s salary is funded through an NIHR Academic Clinical Lecturer award.Declaration of Interest: Dr. Mullins reports other from Department for Health and Social Care, during the conduct of the study. All remaining authors declare no conflict of interest.Ethics Approval Statement: This study utilized PRISMA.