The common cold is a viral infection of your upper respiratory tract — your nose and throat. A common cold is usually harmless, although it may not feel that way at the time. If it's not a runny nose, sore throat and cough, it's the watery eyes, sneezing and congestion — or maybe all of the above. In fact, because any one of more than 100 viruses can cause a common cold, signs and symptoms tend to vary greatly.

Preschool children are at greatest risk of frequent colds, but even healthy adults can expect to have a few colds each year.

Most people recover from a common cold in about a week or two. If symptoms don't improve, see your doctor.

Apr. 17, 2013