Anthrax

Anthrax is a life-threatening infectious disease that normally affects animals, especially ruminants (such as goats, cattle, sheep, and horses). Anthrax can be transmitted to humans by contact with infected animals or their products. In recent years, anthrax has received a great deal of attention as it has become clear that the infection can also be spread by a bioterrorist attack or by biological warfare. Anthrax does not spread from person to person.

The agent of anthrax is a bacterium called Bacillus anthracis. While other investigators discovered the anthrax bacillus, it was a German physician and scientist, Dr. Robert Koch, who proved that the anthrax bacterium was the cause of a disease that affected farm animals in his community. Under the microscope, the bacteria look like large rods. However, in the soil, where they live, anthrax organisms exist in a dormant form called spores. These spores are very hardy and difficult to destroy. The spores have been known to survive in the soil for as long as 48 years.

Anthrax can infect humans in three ways. The most common is infection through the skin, which causes an ugly sore that usually goes away without treatment. Humans and animals can ingest anthrax from carcasses of dead animals that have been contaminated with anthrax. Ingestion of anthrax can cause serious, sometimes fatal disease. The most deadly form is inhalation anthrax. If the spores of anthrax are inhaled, they migrate to lymph glands in the chest where they proliferate, spread, and produce toxins that often cause death.

Source: MedicineNet.com
http://www.medicinenet.com/anthrax/article.htm