Diagnosing the Flu
It is difficult to diagnose the flu. Symptoms such as fever, body aches, fatigue, cough, and sometimes a sore throat and runny nose are similar to the common cold and other illnesses.
A special test given by your doctor is the best way to diagnose the flu. These tests may include swabbing the throat and nose with an absorbent material that is then sent to a laboratory for analysis. This type of test is used in the first three to four days of your illness.
However, flu tests are not 100 percent accurate. Your doctor can best determine if you need to be tested for flu.