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.
In the two years that this scourge ravaged the earth, a fifth of the world's population was infected. The flu was most deadly for people ages 20 to 40. This pattern of morbidity was unusual for influenza which is usually a killer of the elderly and young children. It infected 28% of all Americans (Tice). An estimated 675,000 Americans died of influenza during the pandemic, ten times as many as in the world war.