H1N1 - Medicago

A pandemic influenza is an influenza virus epidemic that spreads globally and infects a large portion of the world’s population. Unlike regular seasonal flu epidemics, influenza pandemics are rare: there have been about nine in the last three hundred years.

The most notorious one is still the 1918 influenza pandemic (“Spanish Flu”), which was caused by a particularly virulent and contagious H1N1 subtype strain, that spread from 1918 to 1919. The 1918 influenza pandemic was responsible for 20 to 50 million deaths in just a few months, particularly among people aged 20 to 35.