Home sick from work the other day, I stumbled on this fascinating online exhibit from the National Archives about the 1918 influenza epidemic, which killed an estimated 50 million people—more than any illness in recorded history, and more people than were killed in World War I. About 25 percent of the American population contracted the flu, and in just one year, the average life expectancy of an American decreased by 12 years.

One of the most interesting documents from the exhibit is a list of precautions that people were advised to take to avoid contracting the disease, including:

Avoid close, stuffy, and poorly ventilated rooms—insist upon fresh air, but avoid disagreeable drafts.
Eat simple, nourishing food and drink plenty of water. Avoid constipation.
Secure at least seven hours sleep. Avoid physical fatigue.
Do not sleep or sit around in damp clothing.
Keep the feet dry.

In San Francisco, city officials fought the spread of the disease by championing gauze masks as 99% effective in preventing the flu, using the slogan: "Obey the laws, And wear the gauze. Protect your jaws from septic paws."

Visit the National Archives site for more pictures and documents related to this often forgotten disaster.

National Archives: Influenza Epidemic of 1918
American Experience: Influenza 1918