Influenza (flu) – Symptoms and causes
OverviewFlu, also called influenza, is an infection of the nose, throat and lungs, which are part of the respiratory system....
OverviewFlu, also called influenza, is an infection of the nose, throat and lungs, which are part of the respiratory system....
Key factsThere are around a billion cases of seasonal influenza annually, including 3–5 million cases of severe illness.It causes 290 000 to...