Anthrax is a disease caused by direct exposure to the bacteria Bacillus anthracis. Anthrax bacteria are very resilient and can survive for many years in a form called a spore. These spores occur naturally in the soil and are sometimes eaten by grazing livestock. When an animal ingests the anthrax spores, the spores can multiply and cause infection. Humans may contract the disease if they handle contaminated products, breathe in spores or eat the undercooked meat of a contaminated animal.

Depending on the way it enters the body, anthrax bacteria can cause three different types of diseases:

• Cutaneous (skin) anthrax.
• Inhalation (lung) anthrax.
• Gastrointestinal (digestive tract) or pharyngeal (throat) anthrax.

Anthrax infections are very rare in the United States. However, in 2001, 22 cases of anthrax were reported after packages containing anthrax spores were mailed throughout the eastern United States. Five people died as a result. Despite the recent bioterrorism incidents, the risk of contracting anthrax in the United States is very low.

The people most at risk for infection are those who work with contaminated animal products on an industrial scale where spores may become airborne. People who may come into contact with anthrax as an agent of bioterrorism (e.g., postal workers, military personnel) are also at risk.

The signs and symptoms of anthrax vary depending on what type of anthrax is contracted. However, the most common symptom of all kinds of anthrax is a flu-like illness, which includes a fever with chills and muscle aches. Because of this similarity, cases of anthrax infection can be confused with influenza or the common cold, possibly delaying vital treatment. The primary difference between anthrax infection and the common cold is the lack of nasal congestion or a runny nose in cases of anthrax.

Most cases of anthrax can be successfully treated with a course of antibiotics. However, it is important that people consult with their physician immediately if they may have been exposed to anthrax spores. Anthrax bacteria produce a toxin that cannot be treated by antibiotics. If left untreated, the toxin can overwhelm the body’s defenses and may cause death.