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Chapter 3

Chapter 3-Six plagues of antiquity.docx
Chapter 3-Six plagues of antiquity.docx

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University of Toronto Scarborough
Health Studies
Caroline Barakat

Chapter 3The Six plagues of Antiquity As humans changed their lifestyles their relationship with infectious diseases came to be altered For 2 million years these human populations consisted of small groups of huntergatherers with limited contact with other such groups and there were no domesticated animals Such a population structure with little or no exposure to new sources of infection and with minimal survival and transmission parasites led to a situation where epidemic diseases were virtually non existent Only diseases with very high transmission rates that induced little or no immunity as well as macro parasitic diseases that did not involve vectors for transmission and sexually transmitted diseases were able to establish themselves in the groups of huntergatherersIt was only until human populations settled down and adopted an agricultural life or continued a nomadic existence that depended on the husbandry of large groups of animals that conditions favoured the emergence of epidemic diseases plaguesAgriculture provided increased amounts of food for the people but it also contributed to conditions that would result in a decline in human healtho The Agricultural Revolution with the cultivation of crops and animal husbandry that provided the driving force for the growth of human cities urbanization Urban life also enhanced the transmission of certain diseases through the air and water by direct contact and by vectors such as snails mosquitoes and flies The diseases with antiquity were characterised by long lived transmission stages as well as those involving person to person contactThe Pharaohs PlagueA look backAssyrian and Babylonan literature as well as the Egyptian papyrus from the Kahun describes a disease that causes blood to appear from the urine called hematuriaSuch a sign was not considered to be connected with disease but to be a mark of puberty in the male child In a relief of the tomb of PtahHetep I and Mehou of the VIth Dynasty at Sakkarah there are figures with enlarged abdomens surely representing the pathology of snail fever or blood fluke diseaseIn 1910 Marc Almand Ruffer examined several Egyptian mummies and found several calcified eggs of the blood fluke in the kidneys of several mummiesFossil snails capable of transmitting blood fluke disease have been found in the well water of Jericho It has been predicted that the water was infested with infected snails resulting in a high level of disease The people of Jericho were so defeated by the disease that they were easily defeated by Joshuas armyThe city remained deserted for 500 years and centuries of recurring drought destroyed all the snails and the city remained free from disease to this daySoon after food production began in the Fertile Crescent it spread to other parts of Eurasia and North Africa The plants and domesticated animals formed the basis for agriculture in the valley s and triggered the rise of Egyptian civilizationEgypt despite its beautiful architecture was deeply affected by snail fever The disease could not be kept under control because o The early civilizations of Europe and those of the Fertile Crescent Summer Assyria and Babylon were based on agriculturewhich required irrigation andor natural flooding by the riverso Irrigation farming especially in the tropics created conditions favourable for the transmission of snail fever caused by the blood fluke o Blood fluke disease is not a fatal disease but its corrosiveo The rule of the pharaohs may have been due to the power of the snail and the blood fluke and malaria the classic plagues of Egyptwhich debilitated the populationo Egypt was subjected to internal political dissension and attack by their ironarmed neighbours the Assyrians and their civilization which was based on agriculture and copper weapons began to collapseo The cause of snail fever was unknown to the Egyptians because the transmission stages of the parasites eggs miracidia and cercariaeare microscopic and the adult worms are tiny and live within small blood vessels Blood fluke DiseaseBlood fluke disease also known as snail fever or endemic hematuria involves feces or urine water snails and a flatwormThe first people to experience this disease was the soldiers of Napoleons army during the invasion of Egypt The symptom of the diseasebloody urine was rife among the soldiers but many believed that it was the excessive heat that caused this conditionBillharz a German physician working in Egypt discovered worms in the blood vesselsSchistosomablood fluke disease is called schistosomiasis or bilhazaria due to Bilharzs discovery In 1851 Bilharz reported seeing microscopic eggs with a pointed spine in a female worm he observed these eggs in the bladder and within the egg he observed a small motile embryoHe found that the egg would hatch to release a small ciliated larva that swam around for about an hour until in disintegrated Also by examining the blood tinged urine under a microscope he found schistosome eggs several of which hatched to give progency that swam by using their ciliaThe suspicion remained that humans acquired the infection either by eating infected snails or by drinking water containing the ciliated larvae called miracidia There were three known species of the human infecting blood flukes Schistosoma japonicium schistosoma mansoni
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