Anthrax is a rare but serious infectious disease caused by the spore-forming bacterium Bacillus anthracis. The bacteria produce spores that can survive in the environment for long periods. Humans can become infected when they come into contact with infected animals, contaminated animal products, or anthrax spores. Anthrax most commonly affects the skin, but it can also affect the lungs or digestive system. The type of illness that develops depends largely on how the bacteria enter the body. Anthrax can be life-threatening if it is not treated promptly. However, early diagnosis and appropriate antibiotic treatment can significantly improve the chances of recovery.
Cutaneous anthrax is the most common form of anthrax. It occurs when anthrax spores enter the body through a cut, scrape, or other break in the skin. It usually begins as a small, itchy bump that may resemble an insect bite. The area can gradually develop into a painless skin sore with a characteristic black center, called an eschar. Swelling may develop around the affected area. Cutaneous anthrax is generally less dangerous than other forms when treated promptly, but the infection can spread into the bloodstream if left untreated.
Inhalation anthrax occurs when a person breathes in anthrax spores. It is also called pulmonary anthrax. Early symptoms may resemble those of a common respiratory infection, including fever, fatigue, cough, muscle aches, and chest discomfort. The illness can then progress rapidly and cause severe breathing difficulties and other serious complications. Inhalation anthrax is uncommon but is considered one of the most serious forms of the disease.
Gastrointestinal anthrax occurs when a person consumes food or meat contaminated with Bacillus anthracis spores. Symptoms may include abdominal pain, nausea, vomiting, fever, loss of appetite, and severe diarrhea, which may sometimes be bloody. The infection can become severe and may spread to the bloodstream. A less common form, oropharyngeal anthrax, can affect the mouth and throat and may cause a sore throat and swelling in the neck.
Anthrax is caused by infection with Bacillus anthracis. The bacterium produces microscopic spores that can remain dormant in soil and other environments for many years. Infection can occur when a person:
Comes into contact with infected animals
Handles contaminated animal hides, wool, hair, or other animal products
Gets anthrax spores into a cut or wound in the skin
Inhales anthrax spores
Consumes contaminated or inadequately cooked meat or other food
Anthrax is not usually spread from person to person through ordinary casual contact. Person-to-person transmission is considered extremely uncommon.
Anthrax can be difficult to diagnose because its early symptoms may resemble other infections. A doctor may consider anthrax when there is a history of exposure to potentially infected animals, animal products, contaminated materials, or an area where anthrax is known to occur. Depending on the suspected form of anthrax, diagnostic testing may include:
Examination of a skin lesion
Testing of a sample from a skin lesion
Blood tests and blood cultures
Respiratory samples
Imaging studies such as a chest X-ray or CT scan when inhalation anthrax is suspected
Testing of other appropriate clinical samples
Because anthrax can progress rapidly, treatment may need to begin before laboratory confirmation when the clinical suspicion is high.
Anthrax is treated with antibiotics. Treatment depends on the type and severity of infection and the patient’s overall condition. Antibiotics that may be used include certain medicines from the fluoroquinolone, tetracycline, or beta-lactam groups, depending on the clinical situation and susceptibility of the organism. People with severe anthrax may require:
Hospitalization
Intravenous antibiotics
Supportive care
Respiratory support
Treatment for complications
Additional therapies in selected severe cases
Treatment should be prescribed and monitored by a qualified healthcare professional. Do not self-medicate with antibiotics if anthrax is suspected.
Preventing exposure to anthrax spores is an important part of reducing the risk of infection. Helpful precautions include:
Avoid contact with animals suspected of having anthrax.
Do not handle or consume meat from animals that died unexpectedly or are suspected to have been infected.
Use appropriate protective equipment when handling potentially contaminated animal products.
Follow workplace safety procedures when working with livestock, animal hides, wool, or laboratory materials.
Seek medical advice after a known or suspected exposure.
Follow local public-health guidance during an anthrax outbreak.
A vaccine against anthrax is available for certain people who have an increased occupational or exposure risk. Vaccination recommendations vary by country and individual circumstances.
Seek urgent medical attention if you develop symptoms that could be consistent with anthrax after a possible exposure to infected animals, contaminated animal products, or anthrax spores. Immediate medical evaluation is especially important if you develop:
A rapidly developing skin lesion with significant swelling
Fever after a known or suspected anthrax exposure
Difficulty breathing or severe cough
Bloody diarrhea
Severe abdominal pain
Swelling of the neck or throat
Severe weakness or confusion
Anthrax can progress quickly, so early medical evaluation and treatment are important.
Anthrax is generally not spread easily from person to person. Most human infections occur after exposure to anthrax spores from infected animals, contaminated animal products, or other contaminated materials.
Yes. Anthrax can be treated with appropriate antibiotics, particularly when treatment is started early. Severe infections may require hospitalization and intensive supportive care.
Yes. Cutaneous anthrax is the most common form. It typically causes an itchy bump that can develop into a characteristic ulcer with a black center and surrounding swelling.
Yes. Eating meat from an animal infected with anthrax can result in gastrointestinal or oropharyngeal anthrax. Meat from animals suspected of having anthrax should not be consumed.
Person-to-person transmission is very uncommon. Anthrax is primarily acquired through environmental or animal-related exposure to Bacillus anthracis spores.
Medical Disclaimer: This article is intended for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. If you have symptoms of anthrax or believe you have been exposed to Bacillus anthracis, seek urgent medical attention and follow the advice of your healthcare professional or local public-health authorities.
