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Anthrax Facts

What is anthrax?

  • Anthrax is an acute infectious disease caused by the spore-forming bacterium Bacillus anthracis. 
  • It is primarily a disease of sheep, goats, cattle and swine, but it can also infect humans. 
  • Symptoms of the disease usually occur within 7 days after exposure and will vary depending on how the disease was contracted. 
  • The 3 serious forms of human anthrax are:
    • Cutaneous anthrax is the most common form of the disease and occurs when the bacterium enters a cut or abrasion on the skin after contact with the tissues of animals dying of the disease. The skin infection begins as a raised itchy bump resembling an insect bite that develops into a skin bubble within 1-2 days and then a painless open sore with a black centre.
    • Inhalation anthrax occurs when the spores are inhaled through the nasal passages. Initial symptoms may resemble a common cold. After several days, the symptoms may progress to severe breathing problems and shock.
    • Intestinal anthrax is rare and more difficult to recognize. It is caused by eating contaminated food and results in acute inflammation of the intestinal tract. Symptoms include nausea, loss of appetite, vomiting, and fever followed by abdominal pain, vomiting of blood, and diarrhea.

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Is there a treatment for anthrax?  

  • Giving preventive antibiotics to a person exposed to anthrax may prevent infection. 
  • Early antibiotic treatment (within 24 hours) is essential since any delays lessen the chance for survival. 
  • The decision to offer preventive antibiotics to those persons exposed is dependent upon the level of exposure.
  • An anthrax vaccine may also prevent anthrax disease. 
  • However, Health Canada advises that there is no need to vaccinate anyone who has not been exposed to the disease.

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A person cannot catch anthrax from someone who is infected with the disease. Therefore, there is no need to treat those around someone ill with anthrax (such as family, friends or co-workers) unless they were also exposed to the same source of the infection.

Content for this page was obtained from the Ministry of Health and Long-Term Care fact sheet "Facts About Anthrax" (Oct. 2001)

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