Human Infections
The past, present, and future interactions of anthrax with human life

           Humans almost invariably contract anthrax is through contact with infected animals.  There are also a few occupations that pose a threat of anthrax contraction, but those careers require vaccinations against the disease.  Thus far into research, there have been no documented cases of human-to-human passing of the disease.  There are three forms of the disease that can be seen in humans: cutaneous anthrax, inhalational anthrax, and gastrointestinal anthrax.

           The cutaneous form accounts for more than 95% of all cases, and is contracted through contact of an infected animal with an open sore of any type.  Signs of cutaneous anthrax are often difficult to spot and this form of anthrax infection is usually painless, but within three to five days, a small pimple (also known as a papule) forms.  Two to three days after appearance of the papule, the center becomes a black, dry scab.  Two to six weeks after the original infection, the scab disappears, whether or not proper treatment has been administered.  The only lingering side effect that proves the infection ever existed is minor scarring that sometimes occurs.  Throughout history, this form has been proven deadly in 20% of all cases, and this is the deadliest form of anthrax.  Reinfection after an original cutaneous infection is extremely rare, and if it does occur, it is much less severe than the original infection. 

           Inhalational anthrax occurs when a large number of anthrax spores are inhaled.  First observed among English mill workers in the 2oth century, this form was quickly given the nickname “Wool-Sorters Disease.”  The first warning sign of this form of anthrax is high fever and chest pain.  Unlike what most people would assume, inhalational anthrax does not cause sporulation in the lungs.  Instead the spores cause an infection in the mediastinal lymph nodes ( which can be found behind the chest bone in the central compartment of the thoracic cavity ).  The toxins that are released cause bleeding in and destruction of the structures in the middle of the chest.  Formerly, inhalational anthrax was thought to be 100% fatal, but recent studies conducted by the Army suggest that as long as antibiotic treatment is started within twenty-four hours of infection, a successful treatment is possible. 

           Gastrointestinal anthrax is extremely rare, and as a result, not very much is known concerning it.  The most common cause of gastrointestinal anthrax is through eating undercooked meat containing Bacillus anthracis spores.  Early symptoms of infection include abdominal pain, nausea, vomiting, bloody stools, loss of appetite, and toxemia; all of which could potentially lead to septicemia, shock, and possible death unless the infection is treated with antibiotics.  In the past fifty years, there have been no reported cases of this form of anthrax in the United States.  Unfortunately, in world-wide cases, gastrointestinal anthrax results in death 25 to 60 percent of the time. 

           Because the rate of human infection is so low, most of the research concerning anthrax today concerns the possibility of use of anthrax in biochemical warfare and because of the possibility of bioterrorist threats.  Throughout history, there have been a few cases of human outbreaks caused by infections other than that of ones obtained through contact with infected animals.  The only occurrence of bioterrorist attacks in the United States occurred in 2001, when anthrax spores were concealed and sent in pieces of mail.  While the attack was meant more as a form of creating fear than as a way to kill a large number of people, it did cause the death of five people out of the twenty-two who were infected.  Some obtained cutaneous anthrax, while others still contracted inhalational anthrax.  Prior to this attack, there had only been eighteen reported cases of inhalational anthrax in the United States in the past one-hundred years — the most recent in 1976.

           Today, several countries are in the process of developing or are believed to have developed a biological warfare program that includes the use of anthrax as a possible chemical weapon.  These countries are the former Soviet Union, Iraq, Japan, South Africa, and the United States.  The main problem concerning the possibility of anthrax as a bioterrorist weapon is that its spores are colorless, odorless, and extremely small. Because of all three of these factors, making an “aerosol” form of the bacteria is a very real possibility.  The only point to the positive is that in order to be made into an effective weapon, a very large quantity of it would have to be manufactured.