Is It a Cold?
Many people confuse the terms "cold" and "flu" because the illnesses share some of the same features. Both are caused by viruses that infect the respiratory tract, mainly in the winter season, and both can cause symptoms such as coughing and sore throat.
Unlike flu, colds typically don't cause fever. A cold is a minor viral infection of the nose and throat and can occur in any season. More than 200 different viruses are known to cause the symptoms of the common cold. Some, such as the rhinoviruses (over 110 distinct varieties), seldom produce serious illnesses. Others, such as parainfluenza and respiratory syncytial virus, produce mild infections in adults but can precipitate severe lower respiratory infections in young children.