Anthrax, a disease of cattle and sheep can also kill humans. The external form of the disease, which sometimes strikes people who handle infected fleeces, causes unpleasant sores. The key to triggering the second form is to create and disperse spore-containing particles of exactly the right size, between one and five micrometers, to ensure that they are retained in the lungs. The spores cross the epithelial lining of the lungs and travel to the lymph nodes, where they germinate, multiply, and then spread to other tissues, releasing toxins as they go. The first symptoms include vomiting, fever, a choking cough, and labored breathing.
Antibiotics can usually cure the earlier stages of the disease.
Without antibiotics, death from hemorrhage, respiratory failure, or toxic shock would follow within a few days. But, only if the particles were no bigger than five microns, or one-twentieth the diameter of a human hair. Otherwise the spores would not be absorbed in the lungs. An accident in 1979 at a Soviet biological warfare plant in Sverdlovsk, now called Ekaterinburg, released a tiny bit of anthrax. There is a licensed human Anthrax vaccine that consists of a series of six doses with yearly boosters.