Possibly have you ever suffered through acute rhinitis? Possibly did you heal from the problem? Obviously you survived it! You won't cure an acute rhinitis directly, but your body typically develops immunity to a particular cold infection within several weeks. That is called treated by your own immune response!

Parents have already had a lot of the cold infections. Adults have actually created immunity to the colds they have had. So there are not quite as many cold viruses remaining for parents to catch. That is why adults just succumb to a few runny noses each year whereas youngsters succumb to a dozen colds annually.
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