CASE CLOSED … what really happened in the 2001 anthrax attacks?

* In 2006, Bruce Ivins’ was having Ames irradiated at 4 Mega Rads

Posted by DXer on June 24, 2015

Screen shot 2015-06-24 at 6.26.28 AM

3 Responses to “* In 2006, Bruce Ivins’ was having Ames irradiated at 4 Mega Rads”

  1. DXer said

    Stupid question: was the strain accidentally sent the Sterne strain? naturally missing its X02 virulence plasmid?

    “What is the Sterne strain (34F2) of Bacillus anthracis?


    The Sterne strain, discovered in the 1930s, has naturally lost its pXO2 plasmid, and consequently its ability to produce a capsule. Compared with normal wild type strains which produce both the toxin and the capsule, the Sterne strain is relatively avirulent, however immunization using the Sterne strain is able to stimulate a protective immune response.

    The Sterne strain is currently the predominant strain used for immunization of domesticated animals against anthrax worldwide, and has been used for this purpose for many decades. It is administered to livestock in a dose containing up to10 million viable spores. The Sterne strain has an excellent safety record, and has been used safely worldwide by laboratory staff involved in its preparation and by hundreds of thousands of veterinarians.

    Can the Sterne strain cause infections in people?

    No human disease due to anthrax caused by the Sterne strain has been reported.

    Theoretically, there are two mechanisms by which the Sterne strain may cause anthrax. First, the toxin alone might be sufficient to cause illness if mechanical protective mechanisms such as skin and mucous membranes are bypassed. In mice, the attenuated strains possess a low degree of virulence, due to toxin production.1-3 The toxin causes occasional losses observed among animals receiving a full dose of vaccine. For this reason, live vaccines have never been considered suitable for human use in the United States.4

    Second, the Sterne strain might regain pXO2 and revert to capsule production, resulting in wild-type virulence. No reversion to virulence has been seen in the Sterne strain since its discovery in 1937.

    What laboratory activities might result in an exposure to the Sterne strain?

    Routine manipulation of the strain in a microbiology laboratory is not likely to result in exposure. Risks to personnel handling this organism are no greater than those posed by other category 2 organisms and activities. Using proper laboratory precautions reduces the risk of percutaneous exposure. Good laboratory practices include the use of appropriate PPE (i.e., gloves, gowns, or laboratory coats) and the use of a biosafety cabinet for procedures with the potential to produce aerosols.5 Eye and face protection (i.e., goggles, masks, or face shields) should be used when splashes or sprays are possible outside of the biosafety cabinet.6

    It is probably not possible for humans to acquire a Sterne strain infection by the respiratory or oral route.7 However, in the event of an accident during routine manipulation, there is a slight risk of infection. In a worst case accident scenario, the risk exists when spores make contact with a preexisting wound, or if an injury results in a contaminated wound. Worst case accident scenarios are estimated to result in 3×10-3 chance of percutaneous infection. With the addition of precautions such as good laboratory practices, appropriate glove use, and training for immediate first aid action, the estimated probability of percutaneous infection drops to 3×10-10. Additionally, the chance of an infection becoming severe or fatal can be reduced to less than 10-14 with the use of antimicrobial agents when necessary.7”

    • DXer said

      Eminent authority, Richard Ebright advises me this morning:

      “At the CDC press conference, it was stated that the first DPG batch identified as viable was Ames and that other DPG batches pending testing included both Ames and other virulent strains.”

      Perhaps some of the other strains were Sterne.

  2. DXer said


    Bruce Ivins experienced repeated irradiation failures with virulent Ames anthrax
    Posted by Lew Weinstein on June 13, 2015

    Bruce Ivins at USAMRIID found it amazing that 6 million rads wasn’t killing the spores
    Posted by Lew Weinstein on June 13, 2015

    Anthrax, Al Qaeda and Ayman Zawahiri: The Infiltration of US Biodefense

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