In 2001, soon after the terrorist attacks of September 11th, 2001(9/11), letters containing anthrax began appearing in the United States (U.S.) mail, becoming the worst biological attacks in the U.S. history. One of the anthrax letters said “ARE YOU AFRAID?” “Yes is still the answer, but of whom?” said Gary Matsumoto, an investigativejournalist in New York City4. The anthrax attack (amerithrax) was one of the largest and most complex cases in the history of law enforcement; the investigation consisted of 30 full-time investigators from the FBI and the U.S. postal services; it expended hundreds of thousands of investigator work hours and lasted until 2010.1 When this case was about to be solved, Ivins, the primary suspect, tookhis own life before the charges could be filed. This paper outlines not only the anthrax attack in 2001, but also the investigation process and the evidence that linked the primary suspect, Bruce Ivins, to the crime.
THE SCIENCE BEHIND THE ANTHRAX
Bacillus anthracis is a Gram-positive, spore-forming, rod-shaped bacterium that causes the anthrax disease. This bacterium can grow in environments withor without oxygen; it just needs carbon and nitrogen sources. Tiny spores of this highly infectious bacterium can survive drought, bitter cold and other harsh conditions for decades, and still infect an animal or human host. Anthrax does not spread directly from one infected animal or person to another; it is spread by spores. These spores can be transported by clothing or shoes as well as thebody of an animal that had active anthrax at the time of death is also a source of anthrax spores.2
Bacillus anthracis spores can cause three kinds of infections: inhalation, cutaneous, and gastrointestinal anthrax. From all of those mentioned above, inhalation anthrax has the highest mortality rate: 90%. One can get inhalation anthrax when breathing in spores from infected animal products andalso if it is used as a biological weapon. Initially its symptoms are like a normal cold, but after several days, these symptoms may get from worse to severe and often fatal breathing problems. Cutaneous anthrax is the most common way of infection. In fact, 95% of anthrax infections are cutaneous anthrax. The infection occurs when the bacteria enter the skin through cut or abrasions, mostly whentouching infected animals. This skin infection begins as an itchy bump, and then turns into a painless ulcer with a black necrotic area in the center. Death is rare if appropriate treatment is received. The last type of infection, gastrointestinal anthrax occurs when consuming infected meat and some of the symptoms include: severe stomach pain, vomiting blood and severe diarrhea. This form of anthraxis the rarest form and usually results in fatality rates of 25% to 60% depending on the time of detection.3
Weaponizing anthrax is one of the most effective ways to cause a biological attack due to its mortality rate and its ability to spread. The anthrax powder that was found in the letters was the Ames strain, according to the Federal Bureau of Investigation (FBI) scientists. The spores foundin the letters to the senators Daschle and Leahy were more pure and concentrated than the ones sent to the media. The Ames strain, one of the most virulent strains ever discovered, was isolated from a cow in Texas in 1981, and then shipped to The United States Army Medical Research Institute for infectious diseases (USAMRIID), where it was maintained thereafter5. The Journal of the AmericanMedical Association described the senate anthrax powder as “high spore concentration, uniform particle size, and low electrostatic charge, treated to reduce clumping”. After the initial analysis, the most important characteristic of the spore for the scientists was the remarkable conversion into aerosol. The spores were so concentrated that FBI scientists believed at first that it contained an...