What is the difference between a cold and the flu?
The flu and the common cold are both respiratory illnesses but they are caused by different viruses.  Because these two types of illnesses have similar flu-like symptoms, it can be difficult to tell the difference between them based on symptoms alone.  In general, the flu is worse than the common cold, and symptoms such as fever, body aches, extreme tiredness, and dry cough are more common and intense.  Colds are usually milder than the flu.  People with colds are more likely to have a runny or stuffy nose.