Perchance have you a while ago been down with a common cold? Maybe did you heal from the problem? Certainly you did! You cannot treat an acute rhinitis itself, but your immune system normally establishes resistance to any cold virus within several weeks. We call that healed by your personal immune response!

Adults have previously had a lot of the runny nose viruses. Grownups have established resistance to the ones they have had. Therefore there are not quite as many runny nose infections remaining for adults to acquire. That is why grownups just acquire a few runny noses each year and kids may get a dozen runny noses each year.
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