By any chance have you a while ago endured a cold virus? Likely did you heal from it? Of course you did! You can't cure a runny nose itself, but your body generally establishes resistance to any cold virus within a few weeks. That is called being healed by your very own immune system!

Parents have previously had a lot of the runny nose infections. Grownups have actually established immunity to the viruses they have suffered from. So there are not lots of cold infections existing for adults to become infected with. That is why parents just succumb to a few runny noses each year and kids acquire a dozen colds per year.
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