A new report has suggested that interferons can prevent children from contracting the coronavirus.
Immunologist Professor Luke O'Neill says children's immune systems begin to attack the virus as soon as it enters their body.
He told Pat Kenny younger children have better responses.
"We know that children don't get sick, they get very mild disease, they're usually asymptomatic - and the big question is why."
He said it is very hard to detect viruses in children using PCR tests: "The fact that you can't pick up viruses means they have suburb immune systems, they absolutely serilise themselves from this virus.
"And the most sensitive of all PCR tests cannot pick the virus up: so that confirms that what children have is a spectacular immune system against the virus".
He said a recent study examined three infected children in a household, and found that the virus could not be detected.
"All they ever found was anti-bodies - so in other words as soon as the virus was in their body their immune system kicked in, made anti-bodies and eliminated the virus almost instantaneously".
Testing in adults
Children make interferons - a very important part of the innate immune system.
However these start to fade around the time of adolescence.
Prof O'Neill said: "Anybody under 40 probably has them to some extent - it fades as you get older".
"It's still pretty strong in your 20s, and we know this because young people are broadly speaking protected.
"But kids have a supercharged way to do this".
He said while some children do have symptoms, the virus still cannot be detected.
"There's a very severe thing in children called Multisystem Inflammatory Syndrome... it's a bit like that.
"Even they, you can't detect much virus in them."
"They're having an autoimmune reaction actually... for some reason those kids kick off an autoimmune response.
"But it's a tiny, tiny minority - the vast majority of children are perfectly fine".
These interferons are now being tested in adults.
"If kids can make loads of the interferons, which is the key weapon they're using against the virus, you could now give that to adults.
"And there was a big trial about a month ago of inhaled interferon having an effect, limiting the virus.
"We now know that maybe we can deploy in adults what kids have naturally".