Pediatric infectious disease experts reviewed recent studies of COVID-19 transmission in children and discussed the question: “should schools reopen?”
As more is learned about COVID-19 and the SARS-CoV-2 virus, it appears that children are less affected than adults and experience milder illness. However, there is still a concern that children with few or no symptoms could transmit the infection to others. Several recent studies have looked at patterns of SARS-CoV-2 transmission in children. In a recent issue of Pediatrics, infectious disease experts considered the findings and the public health implications for safely reopening of schools in the fall term.
Children are relatively spared by COVID-19
Pediatric infectious disease experts at University of Vermont’s Larner College of Medicine reviewed several recent studies on COVID-19 transmission between children and others.
A study from the University of Geneva, Switzerland (published in the same issue of Pediatrics) identified Swiss patients under 16 years old with confirmed SARS-CoV-2 infections between March and April 2020. Among over 4,300 patients, 40 were under 16 years. Most children had mild illness, with only seven hospitalized and none requiring ICU admission or SARS-CoV-2 specific therapies. All children had completely recovered by day 7 after diagnosis. Investigation of family contacts and timing of COVID-19 symptoms within the households of the infected children, found that in only three households (8%) was the child the initial case within the family. This suggested that children acquired SARS-CoV-2 from adults rather than transmitting it.
Two studies from China also looked at COVID-19 transmission within households of infected children. A contact tracing study from Quingdao found that of 68 children admitted to hospital with COVID-19, 96% were contacts of previously infected adults. A study in Wuhan, reported that of 10 children hospitalized with COVID-19 only one case showed possible child-to-adult transmission.
Outside the household setting, a report from France described a child with SARS-CoV-2 infection who had contact with over 80 classmates in three schools. None of these contacts became infected with the SARS-CoV-2 virus, whilst transmission of other respiratory infections in the schools, such as influenza, was common. In an Australian study, nine students and nine staff across 15 schools exposed 735 pupils and 128 staff to COVID-19. There were only two reported secondary infections, one case of adult-to-child transmission and in the other case a student was possibly infected by two classmates. There were no cases child-to-adult transmission in this study.
School-aged children are not drivers of SARS-CoV-2 transmission
The evidence and experience collected so far suggests that schools may not be as important in community transmission of SARS-Cov-2 infection as previously thought. “The key takeaway is that children are not driving the pandemic,” said Dr. William Raszka, co-author of the commentary “… children are less likely to become infected and seem less infectious”
It is still unclear why children seem less likely to transmit SARS-CoV-2 infection, since a German study showed that they carry a similar viral load to adults. It may be related to their milder symptoms – such as less frequent cough – meaning that they release fewer infectious particles
Dr. Raszka and co-author Dr. Benjamin Lee added that mathematical modelling further supports the evidence that children are not significant transmitters of SARS-CoV-2. The models show that community-wide social distancing and widespread wearing of face masks are better strategies for limiting SARS-CoV-2 spread than closing schools. In addition, school reopenings in many Western European countries and in Japan have not led to a rise in community transmissions.
The authors conclude that the current evidence provides a strong argument for developing public health strategies that allow schools to reopen safely and remain open even during periods of COVID-19 spread. “By doing so, we could minimize the potentially profound adverse social, developmental, and health costs that our children will continue to suffer until an effective treatment or vaccine can be developed and distributed,” say the authors.
Written by Julie McShane MA MB BS
References
1. Posfay-Barbe KM, Wagner N, Gauthrey M, et al. COVID-19 in children and the dynamics of infection in families. Pediatrics Published online July 10, 2020. DOI: https://doi.org/10.1542/peds.2020-1576
2. Lee B, Raszka WV. COVID-19 transmission and children: the child is not to blame. Pediatrics Published online July 10, 2020. DOI: https://doi.org/10.1542/peds.2020-004879
3. University of Vermont, Press release 10 Jul 2020. Commentary in pediatrics: children don’t transmit COVID-19, schools should reopen in fall. https://www.eurkalert.org/pub.releases/2020-07/uov-cip070720.php
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