In 1918, the Spanish flu pandemic hit the
world and became one of the worst
pandemics in history.
Approximately 20 to 40 percent of the worldwide population became ill and estimates for the number of people who died during that pandemic range from 20 million to 50 million. In America, the flu killed more than 600,000 Americans--more than all the combat deaths of the 20th century combined.
There were other influenza pandemics in the 20th century:
During the Asian Flu, the virus H2N2 started in China in February 1957, by June 1957 it spread to U.S. and caused 70,000 deaths in U.S.
During the Hong Kong Flu the virus H3N2 started in Hong Kong in early 1968. Later in the year, it spread to the U.S. and caused 34,000 deaths.
