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.
Typhoid fever was the major killer in the Spanish-American war of 1898 as well. Due to vaccinations and advances in public sanitation, the incidence of typhoid fever in developed countries plummeted to approximately 5 cases per one million people per year. Nevertheless, outbreaks caused by other Salmonella serovars are commonly observed.