It found children are eight times more likely to naturally have antibodies that help fight off the infection – despite never having COVID-19.
Scientists from the Francis Crick Institute analysed 300 blood samples collected before the crisis, Sun reported.
It shows children had antibodies against cold bugs that also offer some protection from COVID, which comes from the same family of viruses.
Experts found 43.8 per cent of under-16s had these "cross-reactive" antibodies, compared to just 5.3 per cent of adults.
It may go some way to explaining why youngsters are much less likely to fall seriously ill with COVID.
Lead researcher Kevin Ng, lead author from the Crick, said: “Our results show that children are much more likely to have these cross-reactive antibodies than adults.
“More research is needed to understand why this is, but it could be down to children being more regularly exposed to other coronaviruses.
“These higher levels we observed in children could also help explain why they are less likely to become severely ill with COVID-19.
“There is no evidence yet, however, that these antibodies prevent SARS-CoV-2 infection or spread.”
The findings, published in the journal Science [pls keep], show the cross-reactive cold antibodies do help to neutralise COVID-19.
Now experts are trying to figure out why kids are much more likely to have them than adults.
Just 22 people under the age of 20 have died of COVID in England, out of a total of 34,091 hospital fatalities.
Researcher George Kassiotis, also from the Crick, said antibodies made against other colds can still spot COVID-19.
He added: “This is exciting as understanding the basis for this activity could lead to vaccines that work against a range of coronaviruses, including the common cold strains, as well as SARS-CoV-2 and any future pandemic strains.”