The common cold is a mild illness caused by a virus. More than 200 different viruses are known to cause it. Symptoms usually begin two to three days after infection and include sore throat, coughing, runny nose, and fever. Currently, there is no cure for the common cold other than time. Treatment options include bed rest, drinking lots of fluids, and taking medicine that relieves your symptoms.
Sneezing, runny nose, scratchy throat -- everyone knows the first signs of a cold, probably the most common illness known to exist. Although the common cold is usually mild, with symptoms lasting one to two weeks, it is a leading cause of doctor visits and missed days from school and work.
According to the Centers for Disease Control and Prevention (CDC), 22 million school days are lost annually in the United States due to the common cold. In the course of a year, people in the United States suffer 1 billion colds, according to some estimates.
Children have about six to ten colds a year. One important reason why they are so common in children is because they are often in close contact with each other in daycare centers and schools. In families with children in school, the number of colds per child can be as high as 12 a year.
Adults average about two to four colds a year, although the range varies widely. Women, especially those age 20 to 30, have more colds than men, possibly because of their closer contact with children. On average, people older than 60 have fewer than one cold a year.
The common cold is caused by a virus. More than 200 different viruses are known to cause the common cold. Some viruses, such as rhinoviruses, seldom produce serious illnesses. Other viruses, such as parainfluenza and respiratory syncytial virus, produce only mild infections in adults, but can cause severe lower respiratory infections in young children.
(Click Causes of Common Cold for more information.)