Influenza (the “flu”) is a seasonal respiratory illness caused by flu viruses. The viruses can cause mild to severe illness sometimes resulting in death. It is important to note that the flu is different from a common cold or seasonal allergies. Generally, the onset of the flu is sudden and symptoms include fever (usually high), headache, chills, sore throat, runny or stuffy nose, dry cough, severe exhaustion, muscle aches and stomach symptoms, such as nausea, vomiting and diarrhea