Of all recorded outbreaks of the flu, the most severe was the 1918 Spanish flu in which 20 million people were killed worldwide. More recent ones occurred in 2003 and 2005. Outbreaks are characterized by a new flu virus that spreads easily from person to person. Furthermore, the virus is able to quickly travel around the world, causing serious illness and death.
Flu Outbreaks: An Overview
A flu pandemic entails:
- An emergence of a new flu virus (or a flu virus that has not circulated in many years)
- The ability of the new flu virus to spread easily from person to person
- The ability of the new flu virus to quickly travel around the world and cause serious illness and death for millions of people.
The 1918 flu ("Spanish flu") pandemic is the catastrophe against which all modern flus are measured. More than 20 million people were killed worldwide; 500,000 died in the United States alone. So far, the world has not seen a virus that severe since this pandemic.
(Click 1918 Flu for more information about the 1918 flu pandemic.)
In 1957 and 1968, the Asian flu and Hong Kong flu, respectively, invaded the United States. Although hundreds of thousands of people in the United States died, the death toll for each pandemic was not as high as that for the Spanish flu.
In 1976, the United States experienced a swine flu scare. When a new flu virus was first identified at Fort Dix, New Jersey, it was labeled the "killer flu," and health experts were afraid that it would infect people around the world. However, swine flu never left the Fort Dix area. Research on the virus later showed that if it had spread, it would probably have been much less deadly than the Spanish flu.