Asian Flu
The Asian Flu of 1956-1958 was a category 2 flu pandemic that originated in China and quickly spread as far as the US. Here, around 69,800 people died though worldwide estimates vary significantly.
Some sources claim that the Asian Flu killed 1 million people, other sources say the numbers are closer to 4 million. But overall, the World Health Organization reports that the outbreak caused the deaths of around 2 million people.
Some experts believe that the virus originated from a mutation in wild ducks which later combined with pre-existing human strains. A vaccine was developed in 1957, though smaller outbreaks were later confirmed due to an antigenic shift into H3N2.
