Transmission of the Plague to Humans

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Transmission of the Plague to Humans


Yersinia pestis is a bacterium that has been well known to mankind for centuries. Its mechanisms of survival in wide variety of species are extraordinary. The power of this bacterium is dependent on its manipulation of the immune system of its host’s. Its means of survival in the flea and its use of the flea as a vector to other desirable hosts portray this bacterium’s true capability. This flea is the main cause of the bacterium to other animals, especially humans. However, the bacterium does not just stop here; it uses its coded proteins to inhibit the host’s immune system and the host’s cellular functions to aid in its survival in the organism.

One of the most deadly diseases to strike mankind is the plague. The plague has survived for centuries and has claimed the lives of millions throughout the years. The plague is caused by a gram-negative bacterium known as Yersinia pestis. There have been three major pandemics due to this bacterium. Although it does not seem as deadly now as it was in the Middle Ages, it is still very much alive and present. There are three types of plague: the bubonic, septicemic and pneumonic plague. The bubonic and septicimic plague are only transmitted by the flea, but the pneumonic plague can spread through the air in droplets or by physical contact. At times, transmission can also occur from infected rodents, cats or other animals through bites and scratches (Phillips, 2004). The bacteria’s key for survival lies in its vast variety of hosts. Its mechanism in manipulating the host’s cellular functions has enabled it to take control and survive through the years. However, the process that the bacteria must go through in order to infect a human relie...

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