The Plague


“The bodies of the sick were covered with black pustules…

The symptoms of immediate death.”

Procopius in Constantinople, writing history for the emperor in 541


1(A drawing of plague victims showing the characteristic lesions, buboes,


            Yersinia pestis is the agent of the plague.  There are three distinct syndromes of infection with this organism and each syndrome exhibits unique signs and symptoms.  The three syndromes are bubonic, pneumonic, and septicemic.  They may occur individually or in combination with one another (Bean 425).


Figure 2

          Bubonic Plague is the most common form of plague, but is the least toxic, with a mortality of 50-60%.  This form of plague is caused by a flea bite, and takes its name from the buboes it causes.  Symptoms appear suddenly, usually within 2-5 days of exposure to the bacteria and include:

·         Sudden onset of high fever

·         Smooth, painful swelling of lymph glands, called buboes.  The groin is the most commonly affected area, but swelling may also occur in the armpits or neck.  The areas also become hemorrhagic and discolored.

·         Chills and sweats                                                                                                                                     

·         Severe headache along with other signs of CNS (central nervous system) and psychological dysfunction including delirium, insomnia and stupor.  These changes probably give rise to the strange movements that victims often show which have been described as a danse macabre.

·         Seizures



Pneumonic Plague is rarer than the bubonic variety, but it is more dangerous and deadly.  This form of plague kills over 95% of its victims (Schremmer 2).  The pneumonic plague differs from the other two types in that it is the only form that can be spread from person to person through secretions or droplet exposure.  Symptoms of this plague also occur suddenly, usually 2-3 days after exposure and include:

·         Severe cough

·         Frothy, bloody sputum

·         Difficulty breathing

·         Neurologic and psychologic dysfunction as in bubonic plague

·         Deeply darkened and black skin from hemorrhage and poor circulation, especially of extremities

Buboe caused by Bubonic Plague


Septicemic Plague is the rarest of the three types and like the bubonic plague, it is transmitted by fleas.  Its distinguishing feature is that it can cause death within a day of infection.  It is a blood infection that causes:

·         Fever

·         Nausea, vomiting, diarrhea, and abdominal pain

·         Low blood pressure and shock

·         Blood clotting problems

·         Deeply darkened and black skin from hemorrhage and poor circulation, especially of extremities

·         Failure of several or all organ systems



Necrosis typical of the Black Death.





 Necrosis of the foot tissue.





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