The flu is a respiratory illness caused by the influenza virus. Some symptoms of the flu include coughing, sneezing, fever, body aches, congestion, and fatigue. Read more about the flu (and how to prevent it) here:
Dr. Joseph Mercola is one of the most influential physicians online today, and also one of the most controversial. We spoke with the doctor about his website, medical advice, and his response to critics on some hot-button issues.