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How Anthrax Is Weaponized…

2 minute read
Alice Park

Making anthrax bacteria into a biological weapon requires milling the spores into particles small enough to ensure that they remain suspended in the air for long periods of time

1 DRY THE SPORES If they are grown on a culture medium, anthrax spores need to be dried. Because they are so durable, they can be freeze dried, heat dried or spray dried

2 MILL THE SPORES Once the spores are dry, they are ground down to the smallest possible particle size, anywhere from one micron (one spore) to 20 microns. The process adds electrostatic charges to the particles, which makes them clump together

3 NEUTRALIZE THE SPORES Chemicals such as bentonite or silica are added to remove the electrostatic charge and allow the tiny particles to float in the air


In order to cause disease, at least 8,000 to 10,000 spores need to lodge deep in the lungs, in the tiniest air sacs known as alveoli. The warm, moist environment, and possibly the concentration of carbon dioxide in the lungs, stimulates the bacterium to emerge from its protective spore. As each bacterium reproduces, it releases toxins, which eventually spread throughout the body and destroy tissue and organs


1 TOXINS RELEASED Anthrax bacteria emit three different toxins, all of which eventually combine

2 TOXINS ATTACH TO CELL One of the toxins, called protective antigen, attaches to a receptor found on most cells. When seven of them find their mark, they latch together, forming a ring with a hole in its center. Then one of the other toxins–either a killing toxin or a swelling toxin–plugs the hole

3 TOXINS ENTER CELL The entire complex, encased in a bubble, drops into the cell and starts ejecting its lethal cargo

4 TOXINS DESTROY CELL The killing and swelling toxins put the immune system into overdrive, revving up the body’s defensive system to the point at which it starts destroying tissue


–CIPRO and other antibiotics kill bacteria by interfering with an enzyme that the bugs need to create their DNA

–ANTITOXINS do not yet exist against anthrax, but scientists are working on compounds that would soak up the toxins before they could bind to cells


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