The Black Death
Hunter- gatherers Industrialization Agriculture Human Population
Crowd diseases: –Parasites, e.g. schistosomiasis –Contagious diseases, e.g. measles Epidemics Domesticated animals
Endemic disease, Epidemics and Pandemics The Three Great Pandemics The Biology of Plague
6 th and 7 th Centuries AD
The Medieval Pandemic
The Modern Pandemic
The Biology of Plague Bacillus: Yersinia pestis
The Biology of Plague Rattus rattus (Black Rat)
The Biology of Plague Flea: Xenopsylla cheopis
Types of Plague Primary Bubonic –Transmitted by fleas –Buboes –60-90% mortality
Types of Plague - 2 Primary bacteraemic (septicaemic) Secondary bacteraemic Primary pneumonic Secondary pneumonic –Transmitted by air- borne droplets –Not too infectious
The Black Death Origins in Central Asia, ca Slow rate of spread Importance of Mongol Empire Spreads from Tatars to Genoese colony of Caffa From there to Europe in September 1347
How Many People Died?
Burials at Givry,
Plague Mortality in Bombay Presidency, LocalityPopulationDeath Rate/1,000 Bombay806, Poona161, Karachi97, Sholapur61, Kale4, Supne2, Ibrampur1,
Average Duration of Life: Florence, YearsAverage Life
How Many People Died?: Conclusion Ca. one-half of population dies Population declines until ca. 1425, when stabilizes at one-third level of that of 1300 Remains at this low level until ca Returns to level of 1300 around 1600
But Was It Plague?
Two types of rat needed Rattus norvegicus (brown rat) did not reach England until 1700s
Rodent reservoir But was it plague?
But Was It Plague? Two types of rat needed Rattus norvegicus (brown rat) did not reach England until 1700s
But was it plague? Plague a disease of open steppes, and/or warm countries, but Spreads to Iceland and Greenland
No reports of dead rats 40 day disease cycle, as opposed to 7-10 days for plague
Or a Viral Hemorrhagic Fever? Characterized by bleeding and vomiting of blood Generalized necrosis Affected domestic animals Spread from human to human
Population Movement at Prato
Consequences Western Europe: “Golden Age” of the Peasantry –Rents decline –Wages rise –Serfdom disappears in W. Europe
Population Movements: England
Consequences - 2 Intensifies political and social conflict –“Seigneurial reaction” –Peasant revolts/urban worker revolts –Increased competition among aristocrats for control of shrinking numbers of peasant, leading to Increased civil war Increased inter-state war