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.
Measles affects about 20 million people a year, primarily in the developing areas of Africa and Asia. It causes the most vaccine-preventable deaths of any disease. It resulted in about 73,000 deaths in 2014, down from 545,000 deaths in 1990. In 1980, the disease was estimated to have caused 2.6 million deaths per year.