What the flu does to your body

Influenza virus causes an infection in the respiratory tract, or nose, throat and lungs. The virus is inhaled or transmitted, usually via your fingers, to the mucous membranes of the mouth, nose or eyes. It then travels down the respiratory tract and binds to epithelial cells lining the lung airways via specific molecules on the cell surface. Once inside the cells, the virus hijacks the protein manufacturing machinery of the cell to generate its own viral proteins and create more viral particles. Once mature viral particles are produced, they are released from the cell and can then go on to invade adjacent cells.

Explanation:

The influenza virus primarily attacks your respiratory tract: your nose, throat, and the tubes that lead to your lungs. So symptoms like a runny nose, a phlegmy cough, and a sore throat all make a lot of sense. ... Though other organs in the body are not the primary target, the virus still has an effect on them.