Anthrax | |
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Other names | Anthrax disease |
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A skin lesion caused by anthrax; the characteristic black eschar | |
Specialty | Infectious disease |
Symptoms | Skin form: small blister with surrounding swelling Inhalational form: fever, chest pain, shortness of breath Intestinal form: nausea, vomiting, diarrhea, abdominal pain Injection form: fever, abscess [1] |
Usual onset | 1 day to 2 months post contact [1] |
Causes | Bacillus anthracis [2] |
Risk factors | Working with animals, travelers, postal workers, military personnel [3] |
Diagnostic method | Based on antibodies or toxin in the blood, microbial culture [4] |
Prevention | Anthrax vaccination, antibiotics [3] [5] |
Treatment | Antibiotics, antitoxin [6] |
Prognosis | 20–80% die without treatment [5] [7] |
Frequency | >2,000 cases per year [8] |
Anthrax is an infection caused by the bacterium Bacillus anthracis. [2] It can occur in four forms: skin, lungs, intestinal, and injection. [9] Symptom onset occurs between one day to over two months after the infection is contracted. [1] The skin form presents with a small blister with surrounding swelling that often turns into a painless ulcer with a black center. [1] The inhalation form presents with fever, chest pain, and shortness of breath. [1] The intestinal form presents with diarrhea which may contain blood, abdominal pains, nausea, and vomiting. [1] The injection form presents with fever and an abscess at the site of drug injection. [1]
Anthrax is spread by contact with the bacterium's spores, which often appear in infectious animal products. [10] Contact is by breathing, eating, or through an area of broken skin. [10] It does not typically spread directly between people. [10] Risk factors include people who work with animals or animal products, travelers, postal workers, and military personnel. [3] Diagnosis can be confirmed by finding antibodies or the toxin in the blood or by culture of a sample from the infected site. [4]
Anthrax vaccination is recommended for people who are at high risk of infection. [3] Immunizing animals against anthrax is recommended in areas where previous infections have occurred. [10] A two-months' course of antibiotics such as ciprofloxacin, levofloxacin, and doxycycline after exposure can also prevent infection. [5] If infection occurs, treatment is with antibiotics and possibly antitoxin. [6] The type and number of antibiotics used depends on the type of infection. [5] Antitoxin is recommended for those with widespread infection. [5]
Although a rare disease, human anthrax, when it does occur, is most common in Africa and central and southern Asia. [11] It also occurs more regularly in Southern Europe than elsewhere on the continent, and is uncommon in Northern Europe and North America. [12] Globally, at least 2,000 cases occur a year with about two cases a year in the United States. [8] [13] Skin infections represent more than 95% of cases. [7] Without treatment, the risk of death from skin anthrax is 24%. [5] For intestinal infection, the risk of death is 25 to 75%, while respiratory anthrax has a mortality of 50 to 80%, even with treatment. [5] [7] Until the 20th century, anthrax infections killed hundreds of thousands of people and animals each year. [14] Anthrax has been developed as a weapon by a number of countries. [7] In plant-eating animals, infection occurs when they eat or breathe in the spores while grazing. [11] Animals may become infected by eating infected animals. [11]