So weit ja:
The findings suggest that as schools reopen, communities will see clusters of infection take root that include children of all ages, several experts cautioned.
“I fear that there has been this sense that kids just won’t get infected or don’t get infected in the same way as adults and that, therefore, they’re almost like a bubbled population,” said Michael Osterholm, an infectious diseases expert at the University of Minnesota.
Ebenso wichtig:
The first person in a household to develop symptoms is not necessarily the first to have been infected, and the researchers acknowledged this limitation. Children are also less likely than adults to show symptoms, so the study may have underestimated the number of children who set off the chain of transmission within their households.
Und weiter zu den Kids unter 10:
Children under 10 were roughly half as likely as adults to spread the virus to others, consistent with other studies. That may be because children generally exhale less air — and therefore less virus-laden air — or because they exhale that air closer to the ground, making it less likely that adults would breathe it in.
Even so, the number of new infections seeded by children may rise when schools reopen, the study authors cautioned. “Young children may show higher attack rates when the school closure ends, contributing to community transmission of Covid-19,” they wrote. Other studies have also suggested that the large number of contacts for schoolchildren, who interact with dozens of others for a good part of the day, may cancel out their smaller risk of infecting others.
The researchers traced the contacts only of children who felt ill, so it’s still unclear how efficiently asymptomatic children spread the virus, said Caitlin Rivers, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health.
Aus dem Grund sowas „(kleine) Kinder infizieren wesentlich weniger“ mit Vorsicht zu genießen.
Wobei sich solche Sache ein klein wenig überheblich lesen 
Several studies from Europe and Asia have suggested that young children are less likely to get infected and to spread the virus. But most of those studies were small and flawed, said Dr. Ashish Jha, director of the Harvard Global Health Institute.
The new study “is very carefully done, it’s systematic and looks at a very large population,” Dr. Jha said. “It’s one of the best studies we’ve had to date on this issue.”
Und Herr hatte ich mal gesehen, der die Maske nur halb auf hatte und als er die Bahn verlassen hatte, über das ganze Gesicht zog. Hinter das System bin ich nicht ganz gestiegen.