The Spanish flu swept across the world in three waves between 1918 and 1919 and killed up to three times the amount of people that died in World War One. It tended to stay in a location for up to 12 weeks and then would suddenly disappear, almost as quickly as it had arrived, only to return several months later.
The Spanish flu reached Australia in 1919; it was held at bay partly by strict maritime quarantines implemented by the government. The virus began in Victoria, moved to New South Wales and then to the rest of Australia. By the end of 1919 (when the Australian population was a little more than five million), approximately 10,000 Australians, mostly young adults between the ages of 15 and 35, had died of influenza.