"Nurse wearing a mask as protection against influenza. September 13, 1918."
The influenza epidemic of 1918 first emerged without warning in late spring of 1918, and was known as the “three-day fever.” Few deaths were reported and victims recovered after a few days. When the disease surfaced again that fall, it was far more severe. One fifth of the world’s population was attacked by this deadly virus. Within months, it had killed more people than any other illness in recorded history.