And sure you will eventually acquire another cold virus, since there exist over 300 different runny nose infections. But you will never ever acquire the exact same cold virus that you had previously because you have established resistance to that particular virus.Adults have actually already had a great deal of the runny nose infections. Adults have acquired resistance to the viruses they have suffered from. Therefore there are not as many runny nose viruses around for grownups to catch. That is why adults just get a few runny noses annually and youngsters may get 10-12 colds annually.