Right now, we can make roughly 60 million doses domestically of a normal flu vaccine in a normal year, ... But according to recent research, the total amount of antigen required to immunize a person against H5N1 is four times as much as the total amount in a normal flu shot. In a pandemic, nearly everyone would need flu vaccines, but with the current version, we could immunize only 15 million Americans, just over 5% of the country.

Marc Lipsitch