The Spanish influenza was responsible for an estimated 50 million casualties worldwide, more than 2 ½ times the death toll of the first World War. It killed approximately 675,000 Americans alone. It killed indiscriminately; rich, poor, white, black, from all corners of the globe, it showed mercy no one, including the young and strong who seemed to suffer the most. Almost nowhere was spared a visit from the Spanish Lady.

Nothing was unaffected by the flu. Many small businesses failed due to restrictions on public gatherings and illness. Insurance companies saw an enormous jump in life insurance claims, with one company reporting a 745% rise.  In one year, the life expectancy of Americans dropped twelve years due to the increased mortality. Schools, churches, pool halls, and other places of public gathering were shuttered. In some larger cities, such as Philadelphia, they ran out of coffins. Then undertakers.  Then gravediggers. Hundreds of people were buried in mass graves, and bodies were often left on porches, in unused rooms, or literally shoved into the corners of houses because there was no place to put them and no one healthy enough to do anything about it. Doctors and nurses, expected to care for the sick, got sick themselves. The nursing shortage was so bad in places that people would advertise for skilled nursing help, offering exorbitant salaries. Families frequently had two or more members sick at the same time; a few families were entirely wiped out due to illness, often leaving an orphaned child behind.

Perhaps because of its appearance at the end of World War I, and the heavy censorship of time, the influenza of 1918 left little trace in human memory and is often referred to as "the forgotten epidemic." The flu was fast moving; the war, which lasted far longer, caused greater and more lasting changes in the societies of the time. Alfred Crosby, a historian of the Spanish flu, wrote that "the disease moved too fast, arrived, flourished and was gone before…before many people had time to fully realize just how great was the danger."