"Adult humans' immune systems tend to go all-out to finish off the virus in a campaign that nearly always ends in failure. Children have a relatively tolerant

"Adult humans' immune systems tend to go all-out to finish off the virus in a campaign that nearly always ends in failure. Children have a relatively tolerant immune system, which becomes more aggressive in adulthood - chickenpox, for example, is far more severe in adults due to the way the immune system reacts. " This is fascinating. It looks like a kid's immune system is in "learning mode" for a while. Which makes sense, gives it time to get exposure to pathogens and compounds.