But with the abundant smallpox stocks, comes a new dilemma: how best to use it. The government, which owns all the available smallpox vaccine, is sticking by its plan to wait to deploy the vaccine until it's necessary.
In a strategy known as "ring containment" the Centers for Disease Control plans to vaccinate in a circle around an infected person -- vaccinating everyone they come into contact with, then people those people come into contact with and so on.
Anthony Fauci of the National Institute of Allergy and Infectious Diseases said, "It has worked in containing outbreaks, so the track record of this is good."
But Bill Bicknell at the Boston University School of Public Health disagrees. "I think it is a flawed strategy that is not in the public health."
Bicknell and others are advocating a voluntary vaccination program -- letting people choose for themselves before a biological attack.
"That decreases the weapon's value," Bicknell said. "And it protects the population far better and makes any attack easier to handle."
But large scale vaccinations could mean large scale problems.
The smallpox vaccine is highly toxic and could be especially dangerous to people with HIV and immune system disorders.
Fauci estimates that one to two people per million will have a serious enough reaction to the vaccine that they could die from it.
Critics of the government plan say it's an easy risks versus benefits scenario: take the risks now, or wait to take the same risks under pressure.