Also called the Seasonal Flu, the 'flu' is short for influenza. It is a viral infection which attacks the respiratory system. Some of its symptoms are coughing, sneezing, headache and fever. It is spread through contact with the virus particles directly from someone else, from contaminated surfaces and objects and from breathing in respiratory droplets in the air that contain virus particles just after someone infected coughs or sneezes. Avoid touching your nose, eyes or mouth after touching a person with the flu or surfaces they have recently touched so you don't introduce the virus to your tissues.