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Anthrax Likely Came from U.S. Military Strain http://www.cosmiverse.com/science10250101.html October 25, 2001 8:00 CDT The bacteria in the recent anthrax attacks throughout America are either a strain created by the U.S. to make anthrax weapons in the 1960s, or very close to it. It is not a strain created by Iraq or the former Soviet Union, mass-produced for weapons. This news comes in response to charges over this past week that the sophistication of the anthrax suggests it was created with the backing of some government, such as Iraq. But bioweapons specialists say that neither the strain nor the physical form of the anthrax is particularly sophisticated. Tom Ridge, President Bush's Homeland Security advisor, stated last week that the anthrax sent to Florida, NBC, and Senator Tom Daschle were all the same strain. An FBI spokesman in Florida also confirmed that this was the Ames strain. However, some confusion has mounted over what exactly 'Ames' means. The scientists studying the anthrax are comparing its DNA with a library of strains collected from all over the world. The standard Ames strain is the one used by the U.S. when it produced anthrax weapons, which ended in 1969. To be identified as Ames in the studies going on now, the anthrax must either be the American military strain or one that's very similar. Ames is a good choice for terrorists, as it is likelier than other anthrax strains to cause disease in animals immunized with the standard U.S. anthrax vaccine. The vaccine is now being given to U.S. troops. The Ames strain has proven virulence and is not traceable to one particular country, says Ken Alibek, former deputy head of the Soviet bioweapons program. Alibek says the Soviets did not mass-produce Ames. Iraq used the Vollum strain, which has been identified in samples from its Al Hakam bacterial fermentation plant. The anthrax that was mass-produced for weapons in the US was destroyed after 1969, but samples remained in the U.S. and elsewhere. "The South African collection had hundreds of different strains," said Alibek. Wouter Basson, former head of the South African bioweapons program, reportedly visited Libya after the fall of the apartheid government in 1994. The size of the anthrax particles used in the attacks was reportedly milled down to a few micrometers, making it optimal for inhalation. This has been cited as evidence of state involvement. But "you can use readily available equipment to do this," says Alibek. "It isn't rocket science." The anthrax attacks have resulted in relatively few inhalation cases so far, which indicates that the spores were not blended with anti-caking chemicals to promote airborne spread, which Alibek says is the real secret of making anthrax a weapon. He suspects that the attackers don't have much material to work with. Paul Keim's team at Northern Arizona University in Flagstaff has led the way on the genetic analysis of anthrax bacilli. Team member Kimothy Smith says they have found that some DNA regions mutate frequently, as often as once in every 1000 cell divisions. By comparing the amount of mutation, says Smith, "you can say with a high degree of confidence how many bacterial generations separate an unknown strain from closely related reference strains". This helps pinpoint the exact strain the unknown anthrax came from. It also works for counting the number of cell divisions the bacilli have been through since they parted ways with the most closely related strain. A small batch of anthrax will have gone through many fewer cell divisions than a big batch. Therefore, the analysis could show whether the anthrax came from a 50-liter fermenter or the huge vats of a state-sponsored bioweapons facility. Source: New Scientist -------------------------------------------------------------- To unsubscribe send an email to: [EMAIL PROTECTED] with UNSUBSCRIBE COLEXT as the BODY of the message. Un archivo de colext puede encontrarse en: http://www.mail-archive.com/colext@talklist.com/ cortesia de Anibal Monsalve Salazar
