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Last Updated

13 Dec 2002

Source: Washington Post, October 26, 2001.

U.S. Says Anthrax Germ In Mail Is 'Ames' Strain

Microbe Is of Type Commonly Used in Research

By Rick Weiss and Dan Eggen, Washington Post Staff Writers

Office of Homeland Security Director Tom Ridge said yesterday that the bacterial spores that caused anthrax outbreaks in Florida, New York and Washington belong to the so-called Ames strain -- a subtype of the anthrax bacterium that is commonly used in universities around the world and was a focus of studies by the U.S. military.

Ridge's comments marked the first time that a government official has specified the strain of bacteria that has been sent in letters to Senate Majority Leader Thomas A. Daschle (D-S.D.) and news organizations.

Officials also confirmed that the spores sent to Daschle in a letter opened in his office Oct. 15 were very small, highly concentrated and of high quality.

But they would not answer questions about news reports yesterday that the spores had been treated with a chemical additive to enhance their volatility and make them more likely to cause serious disease. They said ongoing tests could take some time to complete.

Experts have said those tests could narrow the search for the perpetrators of the bio-terrorism attacks.

"We are trying very hard to characterize anything that would be associated with this sample and we're continuing to do that research," Maj. Gen. John Parker of the U.S. Army Medical Research and Materiel Command told reporters at a midday news conference. "And I won't have the absolute answers until all of those investigations are in."

The Washington Post reported yesterday that the spores in the Daschle letter had been treated with a chemical additive using technology so sophisticated that it almost certainly came from the United States, Iraq or the former Soviet Union. A government official with direct knowledge of the investigation has said that the totality of the evidence so far suggests it is unlikely the spores were originally produced in the former Soviet Union or Iraq.

The letter to Daschle is believed responsible for five inhalational anthrax infections -- two of them fatal (case 14 and case 15) -- in the Washington area, though authorities have not ruled out the possibility that there are other undetected letters carrying anthrax microbes.

Ridge said the spores inside the letter sent to Daschle had "some different characteristics" when compared to the spores found in letters sent to NBC News in New York and the New York Post. The letters to the media organizations were postmarked Sept. 18 in Trenton, N.J. The Daschle letter was postmarked Oct. 9 in the same location.

"It is highly concentrated," said Ridge. "It is pure and the spores are smaller. Therefore they're more dangerous, because they can be more easily absorbed in a person's respiratory system." By contrast, the contents of the New York Post letter were clumpy, he said.

It was not immediately clear whether those differences were significant or whether the New York Post sample had simply become sticky from having become damp while in transit.

In other regards, the spores found in all three letters -- as well as those suspected to have caused the Oct. 5 death of a tabloid newspaper photo editor (case 5) in Boca Raton, Fla. -- are indistinguishable, Ridge repeated yesterday. Specifically, he revealed yesterday, they belong to the Ames strain.

That strain was first isolated in Ames, Iowa, and sent in 1980 to Army researchers, who have since distributed it to various academic laboratories.

The strain has spread by other routes to countless research labs around the world, making its identification relatively useless as a tool for tracking the perpetrators, experts have said.

Also yesterday, officials said that investigators in New Jersey have been disappointed to find no evidence of anthrax along the West Trenton postal route of mail carrier Teresa Heller (case 4), whose positive test for the cutaneous form of disease had been seen as a possible lead in the case.

More than 20 tests conducted at the West Trenton post office and in mailboxes and bins along her route turned up negative, FBI officials said, leading them to focus their inquiries on a distribution center in Hamilton Township that feeds into West Trenton.

That facility processed at least three letters containing anthrax spores, and 13 sites out of 23 tested in the building showed signs of anthrax bacteria.