A: The main cause of rapid population growth is when there are more births than there are deaths, which is referred to as a natural increase. Other causes of ... Full Answer >
Spanish flu (1918-1919). The influenza pandemic of 1918-1919 killed more people than the World War I, at somewhere between 20 and 40 million people. It has been cited as the most devastating epidemic in recorded world history. Known as Spanish Flu or La Grippe the influenza of 1918-1920 was a global disaster.
The increased deaths aren't necessarily because the strain of flu virus is stronger, but rather because so many more people get sick during a pandemic, such as: 1  1889 Russian Flu Pandemic: About 1 million flu deaths. 2  1918 Spanish Flu Pandemic: Over 40 to 50 million flu deaths, including about 675,000 in the United States. The flu infected over half of the world's population by the end of the pandemic. 1957 Asian Flu Pandemic: Over 1 million flu deaths, including about 69,800 in the United States