Bacillus Anthracis and Biological Warfare Essay

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Bacillus Anthracis and Biological Warfare

Bacillus anthracis is a rod-shaped, nonmotile, aerobic, gram-positive bacterium that can be transmitted from herbivoric animals to humans (Figure 1). Before an animal’s death, its orifices exude blood containing huge quantities of the bacterium. Anthrax forms extremely resilient spores upon exposure to atmospheric conditions. Because of this spore-producing ability, even after the animal host dies the germs can sporulate again, persisting in the soil for up to several decades (1). No cases of human-to-human transmission have been reported for this zoonosis. Historically, human cases have been either industrial, as with woolsorter’s, or agricultural (2).

Anthrax can be transmitted via 3
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Indeed, most recent outbreaks have occurred in southeastern Asia and Africa where anthrax is endemic, often in isolated villages, and therefore have been difficult to investigate.

Pulmonary anthrax (woolsorter’s disease) results from spore inhalation and like gastric anthrax, is very rare, but inhalation remains the primary infection route for weaponized anthrax, due to its nearly uniform fatality (Table 1). Pulmonary anthrax is approximately 90% fatal, and the US Department of Defense estimates that the human LD50 is between 8,000 and 10,000 spores (5). Some estimates, however, project that the minimum infectious dose could be as high as 80,000 spores (2). As shown in Table 2, early symptoms include malaise, myalgias, fatigue, occasional retronasal pressure, nonproductive cough, and a low-grade fever, and are followed by an acute phase; the acute phase involves respiratory distress, shock, and death (Table 3; 3). Because the early symptoms so closely resemble viral infections or the common cold, anthrax diagnosis proves difficult. While acute phase symptoms are more readily diagnosable, the disease’s advanced progression often makes treatments ineffective at this point (5). Moreover, in the US, there were only 11 reported cases of inhalational anthrax between 1945 and 1994, and so few health physicians have clinical experience with the disease (6). In
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