A U.S. scientist has advised against eliminating the world's last known stocks of smallpox, just weeks before nations are set to reconsider destruction.
"The research agenda with live [smallpox] virus is not yet finished," Inger Damon, who oversees studies of the agent at the Centers for Disease Control and Prevention in Atlanta, said in a newly published article co-authored with two other scientists.
Damon, who heads the agency's Poxvirus and Rabies Branch, and her colleagues argue that related agents cannot always substitute for live smallpox virus in lab experiments to quickly detect and contain the historical scourge, should it re-emerge.
A global eradication campaign wiped out smallpox from nature in the 1970s. However, the United States and other countries have spent decades developing new vaccines and drugs in case the agent is released from a secret stockpile, or assembled from scratch using emerging technologies.
In an interview with Global Security Newswire, Damon advised that state participants in the World Health Assembly -- the top deliberative body of the World Health Organization -- again delay setting any deadline for destroying the final known supplies of smallpox virus. The remaining caches are held at CDC headquarters and at a state laboratory in Russia.
"We can't predict what the results of the next … experiments are going to be," she said by telephone on Wednesday. "If we could do that, we could give a distinct and a definitive [destruction] timeline."
Her article -- written jointly with Clarissa Damaso of Brazil's Federal University of Rio de Janeiro and Grant McFadden of the University of Florida -- makes the case that further research with live virus is "vital" to developing safer vaccines, fully licensed drugs, and faster detection strategies.
Speaking to GSN, Damon said the article does not indicate what position the Obama administration will take at the World Health Assembly's May 19-24 meeting.
She expressed hope, though, that her piece "will be important in informing the official U.S. stance."
Russia and the United States successfully pushed in 2011 to delay any consideration of a destruction deadline until this year. That extended a series of postponements ever since a WHO advisory committee in 1990 recommended destroying the remaining virus.
Advisers to the global health agency reached general agreement in September that live virus stocks "need no longer be retained for further essential research." Its conclusions were echoed two months later by an independent panel of experts convened to examine recent developments in smallpox studies.
Speaking to GSN on Tuesday, epidemiologist Donald Henderson argued in favor of destroying the remaining virus stocks. He recommended focusing on ensuring adequate international supplies of older, less expensive vaccine instead of pursuing further research with live virus.
"We've had a couple of stabs at trying to develop these products as called for by the [United States] way back when, and it hasn't worked," said Henderson, who headed the World Health Organization's global smallpox eradication program in the 1960s and 1970s.
"If it comes to a majority vote in the World Health Assembly, which it's almost come to several times, I think the overwhelming desire will be to destroy," Henderson said.
Henderson and Isao Arita, another former leader of the WHO smallpox eradication effort, wrote in an April journal article that "logic dictates an early date" for the agent's destruction.
Retaining the stockpiles indefinitely, Henderson told GSN, could contribute to international suspicion that Washington and Moscow want the virus as a "deterrent" that they may choose to weaponize.
The virus originated early in human history, and is believed to have killed 300 million people between 1900 and its elimination from the environment.