By chance have you once endured a cold virus? Probably did you heal from the problem? Certainly you recovered! You can't cure a common cold directly, yet your immune system usually creates resistance to a particular cold infection within a few weeks. That is called healed by your personal immune response!

Grownups have in the past had a great deal of the cold viruses. Grownups have created resistance to the colds they have had. So there are not numerous runny nose infections around for grownups to catch. That is why adults just get a couple of colds per year and youngsters usually get a dozen colds per year.
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