What is the black death?
The black death is an vector-borne infectious disease that is caused by the bacterium Yersinia pestis. It is characterized by fevers, vomiting, chills, diarrhea, and the formation of black boils (called "buboes") in the armpits, neck, and groin areas. These boils appear black in color because of the dried blood which fills them from the victim's internal bleeding; this is where the disease gets its name. Occasionally some black death victims have the bacterium spread to the lungs, causing them to fill with bloody liquid (not unlike tuberculosis). This derivation of the disease is called pneumonic plague, as opposed to the bubonic plague wherein the lungs are not affected. There is also a version called septicemic plague, which is characterized by bleeding into the skin (which creates black patches) and other organs, as well as by bite-like bumps that are generally red and sometimes white in the middle. People who die from this form of plague often die on the same day symptoms first appear. The black death works similarly to the HIV/AIDS virus- it takes control of white blood cells and uses them as fuel for replication.