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Facts About Plague

What is plague?

  • Plague is a bacterial infection of rats, ground squirrels, prairie dogs and other rodents on every continent except Australia and Antarctica.
  • There are two kinds of plague infection, bubonic (boo-bahn-ick) and pneumonic (new-mahn-ick).

How is plague spread?

  • Bubonic plague is spread through bites from plague-infected fleas or insects.
  • Typically, human populations become infected after a large number of rats have died from plague, which forces the movement of the flea population from its natural rat reservoir to humans.
  • Bubonic plague is NOT transmitted from person to person.
  • Pneumonic plague is classified as primary or secondary.
  • Primary pneumonic plague is spread through having close contact with a person or animal infected with pneumonic plague.
  • Typically, it is spread from person to person or animal to person, primarily from the mouth and throat droplets or aerosols from the infected person.
  • Pneumonic plague IS transmitted from person to person.
  • Secondary pneumonic plague occurs when the bacteria spread to the lungs through the blood in a person with bubonic plague.

What are the symptoms of plague?

  • Patients develop symptoms of bubonic plague 1-8 days after being bitten by an infected flea.
  • Symptoms present as a sudden onset of fever, chills, weakness, and a swollen or tender lymph node called a bubo, which usually develops within one day.
  • Buboes typically are found in the groin, armpits, or neck regions and can be very painful.
  • Occasionally some people infected with bubonic plague will develop blood infections.
  • Patients typically develop symptoms of pneumonic plague 1-4 days after infection.
  • Symptoms of pneumonic plague include severe pneumonia, chest pain, difficulty breathing, cough and coughing up blood.

How do you know if you have plague?

A physician’s complete and thorough physical examination and laboratory testing are needed to confirm whether or not you have bubonic or pneumonic plague.

How is plague treated?

  • Bubonic and pneumonic plague can be treated with antibiotics.
  • Pneumonic plague can be more serious, and may require advanced supportive medical care and isolation as it IS spread from person to person.

How can you prevent plague?

  • Currently there is no vaccine available to the general public.
  • You can minimize your risk for infection of bubonic plague through good rodent control efforts and limiting your exposure to rodents and wild animals.
  • While pneumonic plague is extremely rare, you can limit your risk of exposure by limiting your contact with infected persons and washing your hands frequently.