The federal Centers for Disease Control and Prevention are investigating how a Frederick research institute mistakenly shipped live anthrax bacteria to a California lab where at least five people were exposed to the potentially deadly germs.
The five vaccine researchers at Children's Hospital Oakland Research Institute were placed on antibiotics, and none has shown symptoms of infection, said Bev Mikalonis, a hospital spokeswoman.
Scientists at Southern Research Institute in Frederick intended to send dead anthrax bacteria to their collaborators in Oakland, said Thomas G. Voss, vice president of homeland security and emerging infectious diseases at SRI.
The killed germs were to be injected into mice to produce antibodies against the disease, one step toward developing an improved vaccine.
But when the mice were inoculated over the past two weeks, nearly all died, prompting the researchers to perform tests to determine the cause of death.
When the tests confirmed that the mice had died of anthrax, state and federal health officials were notified and researchers who had contact with the anthrax samples or the mice were placed on the antibiotic Cipro as a precaution, Mikalonis said.
FBI agents from a bioterrorism unit in San Francisco removed the bacteria from the Oakland facility Wednesday.
Bill Carter, a spokesman at FBI headquarters in Washington, said bureau personnel were called in only because of their equipment and expertise. No wrongdoing is suspected, and no criminal investigation is planned, he said.
CDC experts are investigating the incident to determine why the bacteria were not "inactivated" by the standard procedure of immersion in a hot-water bath, Voss said.
CDC officials could not be reached for comment.
Voss said that before the anthrax was shipped, the sample was tested for the presence of live bacteria, but none was detected.
"We're trying to go through the lab notebooks and make sure we know what was done and how it was done," Voss said. "We may need to increase the sensitivity level on our testing."
Voss said there was no danger to Southern Research personnel because they always use protective equipment in handling anthrax and are vaccinated against the disease.
The anthrax was shipped in March from Frederick to Oakland, where it was stored in test tubes. Voss said even killed bacteria are transported in plastic tubes enclosed in a sealed container inside a secure shipping box.
On May 28, the material was injected into 10 mice, all of which were found dead May 31. A second group of 40 mice were inoculated June 4, and all but one were found dead Monday, Mikalonis said.
Only then did the scientist in charge of the project learn that the mice had died and begin an inquiry, she said.
Southern Research Institute, founded in 1942 and based in Birmingham, Ala., is a not-for-profit organization that conducts research under contracts with the government and private companies.
Its infectious disease branch in Frederick employs 70 people, including 20 who work on biodefense and emerging diseases, Voss said.
The Frederick lab is rated at Biosafety Level 3, the second-highest level of security, Voss said.
That is sufficient to work with anthrax, which the lab has used for research on vaccines, antibiotics and germ detection methods since 2001, he said.