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//(Bacillus anthracis)//
 * ANTHRAX**

[|Todar's Online Textbook of Bacteriology] || Anthrax is a disease caused by the bacteria Bacillus anthracis. Currently, it carries a Category A classification by the Center for Disease Control (CDC) as it is a disease that poses one of the greatest possible threats for a bad effect on public health. It has the ability to spread to humans generally by way of contact with infected animals, or when artificially cultured can be used as a bio weapon in terrorist attacks as in 2001. Anthrax is unable to spread from person to person such as with other bacterial infections. Thanks to the advancements of modern medicine and antibiotics, the survivability of an anthrax infection has increased greatly.
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 * = Gram-stained Bacillus anthracis. Take note of the endospores within and around the bacteria.

Bacillus anthracis is a prokaryotic, Gram-positive, rod-shaped bacteria capable of producing long-lasting endospores. This was the first bacterium Robert Koch cultured and shown to be pathogenic in 1876. When this was cultured and studied, Koch found it would not survive long without a host and would produce endospores under such conditions. These spores have been found to be some of the most resistant of the known classified bacteria today. They are capable of lasting decades and survive in extreme environments where many others would not. It is through these endospores that bacillus anthracis bacteria is able to infect living organisms.

The spores primarily are found dormant in soil where wild or domesticated animals would pick them up. Humans usually contract anthrax through exposure to spores found on or in these infected animals. Regardless, once the spores have found their way to invade the host, they germinate and begin to grow. As the colonies continue to multiply, the released anthrax toxin they produce builds up resulting in a buildup of the various symptoms and potentially leading to their death.

Anthrax Infection

[|CDC Anthrax: Images: Cutaneous Anthrax] ||
 * < [[image:http://www.bt.cdc.gov/agent/anthrax/anthrax-images/images/20-child.jpg width="298" height="288"]] ||
 * = Several examples of a cutaneous infection

There are three types of infection for anthrax (cutaneous, inhalation, and gastrointestinal) based on the entrance process of the endospores into the host. The CDC states that symptoms from the infection usually appear in the host within 7 days, the one contradiction is inhalation anthrax which can incubate anywhere from 7 days up to 42 days for the early symptoms.

Cutaneous anthrax is the most common form of an anthrax infection in humans. Also, it is the most survivable of the three types of infection, and is rarely fatal. Infection occurs when spores of bacillus anthracis enter broken skin or find their way into mucous membranes. The spores will germinate, causing the bacteria to grow and create a sore that eventually could become a necrotic ulcer as the infection progresses. Even with this type of infection residing mainly on the skin, it is possible for the bacteria to spread into the blood stream, which can reduce the chance of survival significantly.

The least common of the three types of anthrax infection, a gastrointestinal anthrax infection usually results from the consumption of undercooked contaminated meat. The CDC lists the mortality rate in the range of 25% to 60% depending on when the infected host seeks treatment. Symptoms of the infection can include: abdominal pain, diarrhea, mouth sores, vomiting (could contain blood), fever, and bloody diarrhea.

Inhalation anthrax (also known as Woolsorters' disease) is the most lethal form of an anthrax infection one could obtain. Spores are inhaled and then colonize the lungs resulting early on with cold or flu-like symptoms. As it progresses, other symptoms such as cough, chest discomfort, shortness of breath, tiredness and muscle aches could likely arise. Due to these indistinct early symptoms, many who are infected don't seek aid until the infection has spread too far. Historically it was seen that an inhalation infection of anthrax had a 92% mortality rate. More recently however, the mortality rate has been seen to be closer to 45% if the infected were to seek out treatment in the early stages of infection.

Treatment and Vaccination

[|Navy.mil] || With an infection of anthrax, early diagnosis and treatment can be critical to the well being and survival of the patient. If the patient was recently exposed, then a mixture of antibiotics and the anthrax vaccine would be used. Infected patients showing symptoms will usually be placed on large doses of antibiotics such as penicillin and doxycycline to attempt to eliminate the infection within the host. If the infected individual is able to overcome their infection, studies have shown that in some cases minor immunity will be granted to that particular strain of anthrax they had been infected with.
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 * = Chief Personnelman Richard L. Billips receiving an injection of the anthrax vaccination

The earliest vaccine created for use against anthrax was by William Smith Greenfield in 1880. Louis Pasteur would be credited with production of the first vaccine for use with livestock in 1881 using Greenfield's technique. The method involved keeping a subculture of the strain at tempatures around 42-45 C would prevent sporulation and reduced the bacteria's virulence. Currently, the main vaccine used in the US for anthrax is Anthrax Vaccine Adsorbed (AVA//)//. It is given in 5 injections across 18 months, with boosters yearly. This vaccine is limited to armed forces and those with high risk of exposure to anthrax, making it unavailable to the general public. The vaccine has obtained some controversy due some evidence of risky side effects and deaths of individuals who had received it. In a published peer-reviewed report covering the vaccine, the National Academy of Sciences found no compelling evidence to suggest there was any increased risk with use of the vaccine over others.

Bioterrorism

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Due to its high lethality and the ease of spreading spores, many have worried about the use of Anthrax as a biological weapon for warfare or terrorism. The disease has had a long history with biological weapon research for many nations over the years. Some of these experiments have led to expanded effectiveness of the disease's virulence and occasional accidental release such as with what occurred in Sverdlovsk, Russia in April of 1979 causing the deaths of nearly 100 people.

A week after the September 11th attacks in 2001, envelopes containing a small amounts of anthrax spores were sent to the offices of various media outlets and the Senate resulting in 22 confirmed infections of anthrax. 11 of those people would contract the inhalation variant of the disease, and 5 would die from that infection. The investigation that followed would take over 8 years before the FBI would declare a culprit and even then there were concerns the investigation's end led to the wrong prosecution.

Resources

Holty, J. E., D. M. Bravata, H. Liu, R. A. Olshen, K. M. McDonald, and D. K. Owens. (2006, Feb 21) Systematic Review: A Century of Inhalational Anthrax Cases from 1900 to 2005. //Ann Intern Med//, Retrieved April 28, 2012, from https://www.ncbi.nlm.nih.gov/pubmed/16490913

Kayabas U, Karahocagil MK, Ozkurt Z, Metan G, Parlak E, Bayindir Y, Kalkan A, Akdeniz H, Parlak M, Simpson AJ, Doganay M. (2012, Feb10) Naturally occurring cutaneous anthrax: antibiotic treatment and outcome. //Chemotherapy//. Retrieved April 28, 2012, from https://www.ncbi.nlm.nih.gov/pubmed/22343361

Artenstein AW, Opal SM.(2012, April) Novel approaches to the treatment of systemic anthrax. //Clin Infect Dis//. Retrieved April 29, 2012, from https://www.ncbi.nlm.nih.gov/pubmed/22438345

Shachtman, Noah (2011, March 24) Anthrax Redux: Did the Feds Nab the Wrong Guy? //Wired//. Retrieved April 19, 2012 http://www.wired.com/magazine/2011/03/ff_anthrax_fbi/all/1

Bergman, Nicholas H. (Eds.). (2001). //Bacillus anthracis and anthrax//. New Jersey: John Wiley & Sons, Inc.

Todar, Kenneth (2012). //Todar's Online Textbook of Bacteriology//. Retrieved April 26, 2012 from textbookofbacteriology.net/

Meselson M, Guillemin J, Hugh-Jones M, //et al.// (November 1994). "The Sverdlovsk anthrax outbreak of 1979". //Science// **266**(5188). Retrieved April 29, 2012 from http://www.sciencemag.org/content/266/5188/1202

Centers for Disease Control and Prevention (2003, July 31). //Anthrax: What You Need To Know.// Retrieved April 10, 2012, from http://www.bt.cdc.gov/agent/anthrax/needtoknow.asp

Centers for Disease Control and Prevention (2003, July 31). //Q&A: Gastrointestinal (GI) Anthrax.// Retrieved April 10, 2012, from http://www.bt.cdc.gov/agent/anthrax/gi/

University of Wisconsin-Madison. (2001). //Anthrax//. Retrieved April 23, 2012 from http://www.news.wisc.edu/anthrax/