CDC Defends Smallpox Retention

The U.S. Centers for Disease Control and Prevention is defending its retention of smallpox stocks, the Atlanta Journal-Constitution reported today (see GSN, Jan. 21).

The United States and Russia are the only countries known to possess live strains of the highly virulent variola virus that was declared eradicated from nature in 1980. The two superpowers have justified their continued retention of the potential bioterrorism material on the grounds that further study is needed for the production of improved vaccines and other countermeasures.

"More work has to be done on the vaccine," CDC spokesman David Daigle said. "We want to make a better vaccine without side effects, and we have much more work to be done (with developing) antivirals."

Last week, the executive body of the World Health Organization supported retaining the smallpox cultures. The full World Health Assembly in May could make a final decision on whether to establish a cutoff date for the smallpox strains to be destroyed.

A significant number of countries want to see the material eliminated, according to the newspaper.

"I think there is probably quite a bit of geopolitical posturing in this," said Inger Damon, who heads the CDC Poxvirus and Rabies Branch.

No more than than 10 scientists at the federal public health agency have access to the Atlanta-based organization's 451 smallpox specimens, which are surrounded by tighter safeguards than those employed for dangerous pathogens such as anthrax, Damon said. Safeguards for the smallpox virus are on par with those used to protect cultures of the Ebola and Marburg viruses.

Washington and Moscow have argued they should be allowed to keep their smallpox strains as it is not definitively known that all other states have destroyed theirs -- thus not closing the door on an inadvertent or deliberate release of the disease or its acquisition by terrorists for a biological weapons attack.

"(Handing over the virus) was a voluntary effort," Damon said. "There was no extensive checking of freezers and checking of vials."

Other nations, particularly developing states, contend that these fears are overstated and that the real danger lies in the accidental release of a U.S. or Russian variola specimen.

"The logic of deterrence doesn't hold in this area," said biological weapons expert Jonathan Tucker, who in a recent article offered a strategy for resolving the impasse (see GSN, Jan. 13). "If we were attacked with smallpox, we wouldn't retaliate with smallpox. That would be morally repugnant."

"At some point, the U.S. has to show more flexibility," Tucker said.

Observers including Tucker believe the United States has developed enough medical countermeasures to fend off an outbreak of the virus. However, a 2010 study by a WHO advisory panel concluded that smallpox strains were still necessary for the development of antiviral medicines in addition to a safer vaccine (see GSN, Jan. 18).

One-time CDC chief Jeffrey Koplan said he thought it unlikely the United States would agree to eliminate its variola cultures, regardless of whether the World Health Assembly votes this spring to establish a deadline for such a project.

"The overriding factor is that politically it would be difficult for any administration to order the destruction of the virus while the Soviet Union still kept it in their fridge," Koplan said (Katie Leslie, Atlanta Journal-Constitution/Apria Healthcare, Jan. 24).

January 24, 2011

The U.S. Centers for Disease Control and Prevention is defending its retention of smallpox stocks, the Atlanta Journal-Constitution reported today (see GSN, Jan. 21).