Common cold: A contagious viral upper respiratory tract infection. The common cold can be caused by many different types of viruses, and the body can never build up resistance to all of them. For this reason, colds are a frequent and recurring problem. Going out into cold weather has no effect on causing a cold. Antibiotics do not cure or shorten the duration of the illness.
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Cold and Flu Resources
Last Editorial Review: 5/13/2016