Ken Alibek explains (in Biohazard) that he was asked how long it would take to “arm” an SS-18 missile with anthrax:
The giant SS-18 missiles, which could carry ten five-hundred-kiloton warheads apiece over a range of six thousand miles, had never been considered before as delivery vehicles for a biological attack.
When the Soviet biological warfare program began in the 1920s, our scientists attached crop sprayers to low-flying planes and hoped that a contrary wind wouldn’t blow the germs the wrong way. After World War II, bombers armed with explosives were added to the arsenal. The Cold War fueled the development of ever more destructive armaments, and by the 1970s we had managed to harness single-warhead intercontinental ballistic missiles for use in the delivery of biological agents. Multiple-warhead missiles represented more of a challenge. Few of the agents we had weaponized could be prepared in sufficient quantities to fill hundreds of warheads simultaneously.
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Through a series of tests, I’d found a way to create a more potent anthrax weapon, so that fewer spores would be needed in an attack. The new technique allowed us to load more missiles with anthrax without straining our labs’ resources.
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At least four hundred kilograms of anthrax, prepared in dry form for use as an aerosol, would be required for ten warheads.
Our seed stock for anthrax production was kept inside refrigerated storerooms at three production facilities in Penza, Kurgan, and Stepnogorsk. The seed stock would have to be put through a delicate fermenting process to breed the billions of spores required. The process was complicated—and it took time. A single twenty-ton fermenter working at full capacity could produce enough spores to fill one missile in one or two days. With additives, we could probably boost the output to five hundred or six hundred kilograms a day.
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The colonels looked pleased. Two weeks was not a problem. No one expected to go to war overnight.
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Anthrax takes one to five days to incubate in the body. Victims often won’t know that an anthrax attack has taken place until after they begin to feel the first symptoms. Even then, the nature of the illness will not at first be clear. The earliest signs of trouble—a slight nasal stuffiness, twinges of pain in the joints, fatigue, and a dry, persistent cough—resemble the onset of a cold or flu. To most people, the symptoms will seem too inconsequential to warrant a visit to the doctor.
In this first stage, pulmonary anthrax can be treated with antibiotics. But it would take a highly alert public health system to recognize the evidence of an anthrax attack.
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The first symptoms are followed several days later by the anthrax “eclipse,” a period in which the initial discomfort seems to fade, concealing the approaching danger. Proliferating bacteria will have begun to engulf the lymph nodes, local headquarters of the body’s disease protection system. Within a matter of hours the bacteria will have taken over the entire lymphatic system. From there, they enter the bloodstream, continuing to multiply at a furious pace. Soon they begin to release a toxin that attacks all organs but is particularly damaging to the lungs, filling them with liquid and gradually cutting off their supply of oxygen.
Within twenty-four hours of this toxin’s release, a victim’s skin will begin to turn a faint bluish color. At this stage, every breath becomes more painful than the last. A choking fit and convulsions follow. The end usually comes suddenly: some victims of pulmonary anthrax have been known to die in the middle of a conversation. The disease is fatal in over 90 percent of untreated cases.
A hundred kilograms of anthrax spores would, in optimal atmospheric conditions, kill up to three million people in any of the densely populated metropolitan areas of the United States. A single SS-18 could wipe out the population of a city as large as New York.