Thunder Pig

The Black Death was, according to chronicles, characterized by buboes (swellings in lymph nodes), like the late 19th century Asian bubonic plague. Scientists and historians at the beginning of the 20th century assumed that the Black Death was an outbreak of the same disease, caused by thebacterium Yersinia pestis and spread by fleas with the help of animals like the black rat (Rattus rattus). However, this view has recently been questioned by some scientists and historians,^[2] and some researchers believe that the illness was, in fact, a haemorrhagic fever based on epidemiological interpretation of historical records of the spread of disease.^[3][4] However, a detailed account of the Great Plague of London of 1665 indicates that the clinical form of the disease of that period is more compatible with bubonic plague.^[5]

The origins of the plague are disputed among scholars. Some historians believe the pandemic began in China or Central Asia (one such location is lakeIssyk Kul)^[6] in the lungs of the bobac variety of marmot, spreading to fleas, to rats, and eventually to humans.^[7] In the late 1320s or 1330s, and during the next years merchants and soldiers carried it over the caravan routes until in 1346 it reached the Crimea in South Eastern Europe. Other scholars believe the plague was endemic in that area. In either case, from Crimea the plague spread to Western Europe and North Africa during the 1340s.^[8][9]The total number of deaths worldwide is estimated at 75 million people,^[10] approximately 25–50 million of which occurred in Europe.^[11][12] The Black Death is estimated to have killed 30% to 60% of Europe's population.^[13][14][15] It may have reduced the world's population from an estimated 450 million to between 350 and 375 million in 1400.^[16]

The plague is thought to have returned every generation with varying virulence and mortalities until the 1700s.^[17] During this period, more than 100 plague epidemics swept across Europe.^[4] On its return in 1603, the plague killed 38,000 Londoners.^[18] Other notable 17th century outbreaks were the Italian Plague of 1629–1631, and theGreat Plague of Seville (1647–1652), the Great Plague of London (1665–1666),^[19] and the Great Plague of Vienna (1679). There is some controversy over the identity of the disease, but in its virulent form, after the Great Plague of Marseille in 1720–1722,^[20] the Great Plague of 1738 (which hit eastern Europe), and the Russian plague of 1770-1772, it seems to have disappeared from Europe in the 19th century.