Plague is a class of dangerous infectious disease mainly caused by the gram-negative, rod-shaped coccobacillus called Yersinia pestis. This bacterium is mainly found in animals like rodents or rats and then it is transmitted through the insects that feed on the blood of these animals. This disease is called by several names: Black Plague – as the black rats are the carrier of this dangerous disease.

It is an old infectious disease that prevailed from the medieval times in the 13th century that took millions of life in Europe. Hence It got the name as ‘Black Death’. This is a deadly contagious disease which spreads from person to person through the air or by any other means of contact. This disease is still in existence in some of the countries like South America, Africa, and many other countries.


The above figure shows a clear picture of how the disease transmits from the bacteria present in the rodent to the human beings.

Types of Plague

There are three kinds of plague:

  • Bubonic plague causes an infection in the lymph nodes of the body. The lymph nodes swell and cause a serious pain. It is transmitted through the fleas that contain the bacteria.
  • Pneumonic plague is a contagious disease that causes infection in the lungs. It is mainly transmitted from one person to another. In this condition, the patient develops several disorders such as chest pain, cough and etc.
  • Septicemic plague- The infection of blood leads to Septicemic plague. This is a condition where the bacteria, almost kills the cells of blood in the human body causing death.

Causes of Plague

Plague is caused by various means of contacts resulting in widespread of the disease.

  • It is caused by means of sneezing.
  • It is even caused by direct physical contact with the infected person.
  • By touching the soil or any surface that is contaminated.
  • Consumption of contaminated foods or water.
  • Bite from the insects which have previously fed on infected animals like a rat, squirrel, rodents, etc.

Symptoms of Plague

Listed below are the few serious symptoms of Plague.

  • Severe fever.
  • Frequent headaches.
  • Muscle and joint pains.
  • Feeling of sickness.
  • Seizures.
  • Breathing problems.
  • A severe cough with pain in the chest region
  • Diarrhea
  • Nausea sensation
  • Vomiting sensation
  • Pain in the abdomen region and etc
  • Swelling in the joints

The necessary treatments for this disease require effective use of antibiotics regularly as this is a deadly kind of disease and good precautionary measures need to be applied to stop the spreading of this disease.

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