Federal health officials say they are investigating the accidental shipment of live anthrax bacteria to labs in nine states. The Centers for Disease Control and Prevention confirms that it's investigating the accidental shipments.
No one's been sickened by the bacteria, which can cause potentially deadly illness although it's easily treated with antibiotics if caught soon enough.
"CDC is investigating the possible inadvertent transfer of a select agent from the U. S. Department of Defense (DOD) to labs in nine states. At this time we do not suspect any risk to the general public," CDC said in a statement sent to NBC News.
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Department of Defense spokesman Col. Steven H. Warren told NBC News the shipments were mistakenly sent out from the U.S. Army's Dugway Proving Ground in Utah.
"The DoD lab was working as part of a DoD effort to develop a field-based test to identify biological threats in the environment," Warren said. "Out of an abundance of caution, DoD has stopped the shipment of this material from its labs pending completion of the investigation."
CDC says the anthrax was being used to develop a test in case someone used the bacteria as part of a bioterror attack.
"The lab was working as part of a DOD effort to develop a new diagnostic test to identify biological threats. Although an inactivated agent was expected, the lab reported they were able to grow live Bacillus anthracis," CDC said.
Live anthrax is supposed to be handled in a biosafety level 3(BSL-3) lab -- one that is equipped to protect workers from the bacteria and from the spores it produces.
"CDC is working in conjunction with state and federal partners to conduct an investigation with all the labs that received samples from the DOD. The ongoing investigation includes determining if the labs also received other live samples, epidemiologic consultation, worker safety review, laboratory analysis, and handling of laboratory waste. "
It's the second mistaken shipment of live anthrax in a year. Last June, CDC said more than 80people may have been exposed to live anthrax when a CDC lab sent it by mistake. Lab workers thought they had inactivated the bacteria.
CDC lab procedures were overhauled after the mishap.
In 2004, a Maryland lab accidentally sent a batch of live anthrax to a children's hospital in California.
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And in 2001, five people died including two postal workers infected after anthrax spores puffed out of anthrax-filled letters as they were processed. The anthrax-laced letters made another 17 people sick. They were sent deliberately in a case that still hasn't been fully resolved.
"All samples involved in the investigation will be securely transferred to CDC or Laboratory Response Network laboratories for further testing. CDC has sent officials from the CDC Federal Select Agent Program to the DOD labs to conduct onsite investigations."
Anthrax can infect people in three ways -- on the skin, in the digestive system or in the lungs. All three types can be dangerous but inhaled anthrax is the most deadly because once it starts causing symptoms it is often too late for antibiotics to help. And the inhaled spores can lurk in the lungs for months before they activate, so someone exposed to the spores may not know what their symptoms mean.