There are four common routes of anthrax infection, each with different signs and symptoms. In most cases, symptoms develop within seven days of exposure to the bacteria. The one exception is inhalation anthrax, which may take weeks after exposure before symptoms appear.

Cutaneous anthrax

A cutaneous anthrax infection enters your body through a cut or other sore on your skin. It's by far the most common route the disease takes. It's also the mildest — with appropriate treatment, cutaneous anthrax is seldom fatal. Signs and symptoms of cutaneous anthrax include:

  • A raised, itchy bump resembling an insect bite that quickly develops into a painless sore with a black center
  • Swelling in the sore and nearby lymph glands

Gastrointestinal anthrax

This form of anthrax infection begins by eating undercooked meat from an infected animal. Signs and symptoms include:

  • Nausea
  • Vomiting
  • Abdominal pain
  • Headache
  • Loss of appetite
  • Fever
  • Severe, bloody diarrhea in the later stages of the disease
  • Sore throat and difficulty swallowing
  • Swollen neck

Inhalation (pulmonary) anthrax

Inhalation anthrax develops when you breathe in anthrax spores. It's the most deadly way to contract the disease, and even with treatment it is often fatal. Initial signs and symptoms of inhalation anthrax include:

  • Flu-like symptoms, such as sore throat, mild fever, fatigue and muscle aches, which may last a few hours or days
  • Mild chest discomfort
  • Shortness of breath
  • Nausea
  • Coughing up blood
  • Painful swallowing

As the disease progresses, you may experience:

  • High fever
  • Trouble breathing
  • Shock
  • Meningitis — a potentially life-threatening inflammation of the brain and spinal cord

Injection anthrax

This is the most recently identified route of anthrax infection. It's contracted through injecting illegal drugs and has been reported only in Europe so far. Initial signs and symptoms of injection anthrax include:

  • Redness at the area of injection (without an area that changes to black)
  • Significant swelling

As the disease progresses, you may experience:

  • Shock
  • Multiple organ failure
  • Meningitis

When to see a doctor

Many common illnesses start with symptoms that resemble the flu. The chances that your sore throat and aching muscles are due to anthrax are extremely small.

If you think you may have been exposed — for example, if you work in an environment where anthrax is likely to occur — see a doctor immediately for evaluation and care. If you develop signs and symptoms of the disorder after exposure to animals or animal products in parts of the world where anthrax is common, seek prompt medical attention. Early diagnosis and treatment are crucial.

Jun. 10, 2014

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