What is the Flu?
Influenza is a common, infectious respiratory disease that begins in your nose and throat. Human influenza, or the flu, is a respiratory infection caused by the influenza virus. Strains circulate every year, making people sick. Influenza typically starts with a headache, chills, and cough, followed rapidly by fever, loss of appetite, muscle aches and fatigue, running nose, sneezing, watery eyes, and throat irritation. Nausea, vomiting, and diarrhea may also occur.
(Adapted from PHAC)