The Plague

Since the reign of Emperor Justinian in 542 A.D., man has one unwelcome organism
along for the ride, Yersinia pestis. This is the bacterium more commonly know as
the Black Death, the plague. Plague is divided into three biotypes, each
associated with one of three major pandemics occurring in history. Each of these
biotypes are then divided into three distinct types, classified by method of

The most widely know is bubonic, an infection of plague that resides in the
lymph nodes, causing them to swell. The Black Death of the 14th century was
mainly of this type. Bubonic plague is commonly spread through fleas that have
made a meal from an infected Rattus rattus. In the American and Canadian west,
from Texas and Oklahoma in the east to the Pacific Ocean in the west, it is most
often transmitted from species of squirrels. The last occurrence of
transmissions from rats to people, or people to people in the United States
occurred in 1924 in Los Angeles. In that epidemic there were 32 cases of
pneumonic plague with 31 fatalities. Since then there have been around 16 cases
a year in the United States, most connected with rock squirrels and its common
flea Oropsylla montana.

The most dangerous type of plague is pneumonic. It can be spread through aerosol
droplets released through coughs, sneezes, or through fluid contact. It may also
become a secondary result of a case of untreated bubonic or septicemic plague.
Although not as common as the bubonic strain, it is more deadly. It has an
untreated mortality rate on nearly 100%, as compared to 50% untreated mortality
for bubonic plague. It attacks the respiratory track, furthering the cycle.

The third type of plague is septemic. It is spread by direct bodily fluid
contact. It may also develop as a secondary result of untreated bubonic or
pneumonic plague.


As mentioned before, the most known incidence of bubonic plague was in 14th
century Europe. In 1346 reports of a terrible pestilence in China, spreading
through Mesopotamia and Asia Minor had reached Europe, but caused no concern
until two years later. In January of 1348 the plague had reached Marseille in
France and Tunis in Africa. By the end of the next year the plague had reached
as far as Norway, Scotland, Prussia, Iceland, and Italy. In 1351 the infection
had spread to include Russia.

The plague was an equal opportunity killer. In Avignon nine bishops were killed,
King Alfonso XI of Castile succumbed, and peasants died wherever they lay.
Though the plague had, for the most part, ceased less than ten years after it
started, it killed nearly one third of the European population. In many towns
the dead outnumbered the living. Bodies piled in the streets faster than nuns,
monks, and relatives could bury them. Many bodies were interred in mass graves,
overflowing with dead, or dumped into nearby rivers. Domesticated cats and dogs,
along with wolves, dug dead out of shallow graves, and sometimes attacked the
still living. Many animals did either from plague or lack of care. Henry
Knighton noted more than 5,000 dead sheep in one field alone.

The death of a very large portion of the work force aided those that were still
living. The sheer scarcity of workers enabled the remainder to make demands of
higher wages and better conditions. Farms located on poor soil were abandoned
because the demand for grain had decreased, enabling fewer farms, located on the
better tracts of land to feed the population.

Category: Science