Pentagon officials say kits containing live anthrax were sent to 51 labs in 17 states and Washington, D.C., and 3 foreign countries -- far more than originally reported. The officials stressed they do not believe the public is in danger from the live spores.
The Pentagon is among the locations that received a shipment of anthrax from a batch that was later found to contain live spores of the deadly bacteria, defense officials told NBC News.
The samples were sent to the Pentagon's police force, which planned to use them in testing and calibrating detection equipment for incoming mail. They were drawn from a batch of anthrax that had been irradiated at the U.S. Army's Dugway Proving Ground in Utah, a method that is supposed to kill any live spores.
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But that process apparently did not completely work; when Dugway retested that batch recently, it was found to contain live spores.
There's no indication that the Pentagon samples contained live spores, and no one in the Pentagon has shown signs of anthrax infection, the defense officials said.
Meanwhile, U.S. officials told NBC News Tuesday that the Centers for Disease Control is expected to order the suspension of all anthrax shipments from any qualified agency until it can be determined why irradiation of several batches of anthrax failed to kill live anthrax spores.
"It's a complete mystery" according to one official who said the CDC wants to suspend all shipments from government and private research labs "as a precaution."
The news followed revelations that three government research labs in Canada received anthrax samples from a 2005 batch of anthrax that recently tested positive for some live spores.
Dugway and the Centers for Disease control are in the process of examining anthrax samples that were sent to government and private research labs in 12 states, to South Korea, Australia and Canada.
Defense officials pointed out that even though several original batches of anthrax at Dugway have tested positive for live anthrax spores, only one private research lab in Maryland has received a sample that has so far tested positive for the live bacteria.
The officials added that no one has come down with an anthrax infection.