Bacillus anthracis is the agent of anthrax—a common disease of livestock and, occasionally, of humans—and the only obligate pathogen within the genus Bacillus. This disease can be classified as a zoonosis, causing infected animals to transmit the disease to humans.
Four forms of human anthrax disease are recognized based on their portal of entry:
Cutaneous, the most common form (95%), causes a localized, inflammatory, black, necrotic lesion (eschar). Most often the sore will appear on the face, neck, arms, or hands. Development can occur within 1-7 days after exposure.
Inhalation, a rare but highly fatal form, is characterized by flu like symptoms, chest discomfort, diaphoresis, and body aches. Development occurs usually a week after exposure, but can take up to two months.
Gastrointestinal, a rare but also fatal (causes death to 25%) type, results from ingestion of spores. Symptoms include: fever and chills, swelling of neck, painful swallowing, hoarseness, nausea and vomiting (especially bloody vomiting), diarrhea, flushing and red eyes, and swelling of abdomen. Symptoms can develop within 1-7 days
Injection, symptoms are similar to those of cutaneous anthrax, but injection anthrax can spread throughout the body faster and can be harder to recognize and treat compared to cutaneous anthrax.. Symptoms include, fever, chills, a group of small bumps or blisters that may itch, appearing where the drug was injected. A painless sore with a black center that appears after the blisters or bumps. Swelling around the sore. Abscesses deep under the skin or in the muscle where the drug was injected.