And definitely you will eventually get one more cold virus, since there remain over 300 different runny nose viruses. Yet you will never get the very same cold infection that you had before due to the fact that you have created immunity to that cold virus.

Adults have previously had a great deal of the cold viruses. Grownups have acquired immunity to the ones they have suffered from. So there are not numerous cold viruses existing for parents to become infected with. That is why adults only succumb to a couple of runny noses per year and kids may get a dozen colds each year.
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