While the world races to control the new strain of H1N1 flu virus, researchers recall a rival to the 1957 Asian flu that killed 2 million people globally.
Scientists are trying to find out whether swine flu will transform and become more deadly as it spreads to the Southern Hemisphere.
The virus has been carried around the world by travelers and acts more like a pandemic strain than a regular seasonal flu, said a study led by Neil Ferguson of the Imperial College London published May 11 in the journal Science.
Seasonal flu epidemics cause 250,000 to 500,000 deaths each year, the World Health Organization estimates. According to the latest updates by the WHO as of May 11, 30 countries have officially reported 4694 cases of influenza H1N1 infection since April 2009.
The swine flu strain and its death toll might rival the severity of the 1957 Asian Flu pandemic that claimed the lives of 2 million people, scientists say.
â€śWhile substantial uncertainty remains, clinical severity appears less than that seen in 1918, but comparable with that seen in 1957,â€ť the Science study authors wrote.
“A ‘moderate’ pandemic characteristic of the 1957 Asian flu could kill 14.2 million people and shave 2 percent from the global economy in the first year,” the World Bank reported in 2008. “Some forecasts have estimated deaths during a ‘severe’ pandemic at as high as 180 million to 260 million,” the report continued.
The Asian Flu of 1957 was a category 2 flu pandemic outbreak of avian influenza that originated in China from a mutation in wild ducks that combined with a pre-existing human strain. It spread to Singapore in February 1957, reached Hong Kong by April, and the US by June.