Overview
The disease can range from mild to severe, with symptoms including fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. Influenza may progress to pneumonia, acute respiratory distress syndrome, meningitis, encephalitis, and worsening of pre-existing health problems. The Centers for Disease Control and Prevention (CDC) recommends that everyone over the age of 6 months receive an influenza vaccine every year. The World Health Organization (WHO) and the CDC work closely together to monitor influenza outbreaks and provide guidance on prevention and treatment.