An influenza pandemic in 1918 killed tens of millions of people worldwide, including 800,000 Americans — a greater death toll than all the casualties of World War I.
Scientists now worry that "bird flu," which has emerged in developing countries in Southeast Asia, could mutate and soon cause another flu pandemic.
Recently, researchers in the U.S. announced they had succeeded in developing a treatment for the virus. But if an outbreak were to occur today, supplies of the drug would be grossly insufficient.
According to the World Health Organization, even if the company with the patent were to produce at full capacity for the next 10 years and stockpile the drug, there would only be enough for 20 percent of the world's population.
There is currently much debate over the possibility of licensing the manufacturing of the drug to other companies to accelerate production. But, given the complexity of the manufacturing process, it could still take years before there's enough to go around.