Anthrax is a serious infectious disease caused by spores of the bacterium, Bacillus anthracis (B. anthracis). The B. anthracis spores are resistant to destruction and are easily spread in the air. In some countries, anthrax is naturally present in the soil, which can infect grazing animals that ingest the spores. Goats, sheep and cattle are examples of animals that may become infected. People can become infected with anthrax when spores get into the body. This can occur through the skin or by inhalation. Although it is rare, people may get anthrax disease through natural exposures, such as contact with infected animals or contaminated animal products. In the United States, human cases of anthrax are rare. Anthrax is considered one of the more likely agents to be used in a biological attack.
The most common form of anthrax infection in humans is through the skin (cutaneous). This can happen when a person has a cut and handles infected animals or contaminated animal products like wool, hides, or hair. Although rarely reported in the United States, eating undercooked or raw meat from an infected animal is another form of anthrax infection (gastrointestinal) in which the anthrax spores can affect the upper gastrointestinal tract (throat and esophagus), stomach, and intestines. Breathing anthrax spores can cause inhalation anthrax. People may breathe in the spores when working with infected animals or contaminated animal products through workplace exposure such as wool mills and slaughterhouses. The death rates from anthrax infection without treatment vary, depending on the type of exposure, and are approximately 20% for cutaneous anthrax, over 50% for gastrointestinal anthrax; and inhalation anthrax is almost always fatal. All types of anthrax infection can be treated with certain antibiotics.
FDA has approved two vaccines, BioThrax and Cyfendus, to prevent disease in persons 18 through 65 years of age following suspected or confirmed Bacillus anthracis exposure, when administered in conjunction with recommended antibacterial drugs. BioThrax is also approved for pre-exposure prophylaxis of disease in persons 18 through 65 years of age who are at high risk of exposure.
The vaccines have been purchased by the federal government and are stored in the Strategic National Stockpile (SNS) to be used for post-exposure prophylaxis with antibiotics in the event of a terrorist attack with anthrax. Likewise, because of biological warfare threats, the military has an active vaccination program against anthrax for personnel going to specific arenas around the world.
FDA has approved Anthrasil, an Anthrax Immune Globulin Intravenous (Human) for the treatment of inhalational anthrax in adult and pediatric patients in combination with appropriate antibacterial drugs.