Influenza (flu) is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness. Serious outcomes of flu infection can result in hospitalization or death.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. But the flu is so much more than that.

A common viral infection that can be deadly, especially in high-risk groups.The flu attacks the lungs, nose and throat. Young children, older adults, pregnant women and people with chronic disease or weak immune systems are at high risk.Structurally, the influenza virus is spherical in shape. It is covered in an envelope made of a lipid bilayer with spikes of glycoproteins called haemagglutinin and neuraminidase. These proteins enable the virus to effectively bind with a host cell.

Symptoms include fever, chills, muscle aches, cough, congestion, runny nose, headaches and fatigue.

Flu is primarily treated with rest and fluid intake to allow the body to fight the infection on its own. Paracetamol may help cure the symptoms but NSAIDs should be avoided. An annual vaccine can help prevent the flu and limit its complications.