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Angela
05-06-19, 00:54
Fascinating stuff. It has to do with the first "recorded" plague pandemic, although we didn't know for sure what it was: Justinian's Plague.

See:
https://www.shh.mpg.de/1332424/plague-pandemic

"An international team of researchers has analyzed human remains from 21 archaeological sites to learn more about the impact and evolution of the plague-causing bacterium Yersinia pestis during the first plague pandemic (541-750 AD). In a study published in PNAS, the researchers reconstructed 8 plague genomes from Britain, Germany, France and Spain and uncovered a previously unknown level of diversity in Y. pestis strains. Additionally, they found the first direct genetic evidence of the Justinianic Plague in the British Isles.The Justinianic Plague began in 541 in the Eastern Roman Empire, ruled at the time by the Emperor Justinian I, and recurrent outbreaks ravaged Europe and the Mediterranean basin for approximately 200 years. Contemporaneous records describe the extent of the pandemic, estimated to have wiped out up to 25% of the population of the Roman world at the time. Recent genetic studies revealed that the bacterium Yersinia pestis was the cause of the disease, but how it had spread and how the strains that appeared over the course of the pandemic were related to each other was previously unknown."

"They were able to reconstruct 8 new Y. pestisgenomes, allowing them to compare these strains to previously published ancient and modern genomes. Additionally, the team found the earliest genetic evidence of plague in Britain, from the Anglo-Saxon site of Edix Hill. By using a combination of archaeological dating and the position of this strain of Y. pestis in its evolutionary tree, the researchers concluded that the genome is likely related to an ambiguously described pestilence in the British Isles in 544 AD.
"The researchers found that there was a previously unknown diversity of strains of Y. pestis circulating in Europe between the 6th and 8th centuries AD."

"The newly discovered genomes revealed that there were multiple, closely related strains of Y. pestis circulating during the 200 years of the First Pandemic, some possibly at the same times and in the same regions."

"Despite the greatly increased number of genomes now available, the researchers were not able to clarify the onset of the Justinianic Plague. “The lineage likely emerged in Central Asia several hundred years before the First Pandemic, but we interpret the current data as insufficient to resolve the origin of the Justinianic Plague as a human epidemic, before it was first reported in Egypt in 541 AD. However, the fact that all genomes belong to the same lineage is indicative of a persistence of plague in Europe or the Mediterranean basin over this time period, instead of multiple reintroductions.”"

It always circles back to Central Asia as the source.

Well isn't this just great...

"Another interesting finding of the study was that plague genomes appearing towards the end of the First Pandemic showed a big deletion in their genetic code that included two virulence factors. Plague genomes from the late stages of the Second Pandemic some 800-1000 years later show a similar deletion covering the same region of the genomes. “This is a possible example of convergent evolution, meaning that these Y. pestis strains independently evolved similar characteristics. Such changes may reflect an adaptation to a distinct ecological niche in Western Eurasia where the plague was circulating during both pandemics,” explains co-first author Maria Spyrou of the Max Planck Institute for the Science of Human History."

bicicleur
05-06-19, 06:26
541 AD in Egypt
the end of the Silk Road?

https://www.pnas.org/content/early/2019/06/03/1820447116?fbclid=IwAR1ZUueQMsZ6uXIWZQLuyH15I5Jajv Zrwrnx7VQxBphd1GvpG-w9iGgCDBA

Angela
05-06-19, 14:51
541 AD in Egypt
the end of the Silk Road?
https://www.pnas.org/content/early/2019/06/03/1820447116?fbclid=IwAR1ZUueQMsZ6uXIWZQLuyH15I5Jajv Zrwrnx7VQxBphd1GvpG-w9iGgCDBA

Yeah, that seems like a really good bet, right?

Interestingly, every once in a while we get a case of the plague in the U.S., and it's usually in the southwest somewhere, in conditions not dissimilar to Central Asia. It's harbored in various rodents. Thing is, there isn't a trade route going through it using animals for transport, and herdsmen don't live there who could go spreading it around the world.

bigsnake49
27-06-19, 19:54
Since it was spread around the trade routes, does that mean that it probably affected the cities and the settlements around the trade routes, the ports, etc. while sparing the interior?

Angela
27-06-19, 20:29
[QUOTE=bigsnake49;580694]Since it was spread around the trade routes, does that mean that it probably affected the cities and the settlements around the trade routes, the ports, etc. while sparing the interior?[/QUOcTE]

It certainly didn't spare inland Lunigiana. The land trade routes went right up through it both for internal trade and to go over the mountains into the north. Fivizzano, where my mother has family, lost close to 90% of its inhabitants.

https://www.tripsavvy.com/thmb/XOieYzQdF2qEolwDhH3v30Dg_us=/1500x1000/filters:fill(auto,1)/lunigiana-map-5675a2c33df78ccc151ce375.jpg
http://3.bp.blogspot.com/-Nrei3k9FN2k/VIIy9HbeQ9I/AAAAAAAAArs/1XHWTrNLfwM/s1600/bdeth.gif

A small isolated area might be more spared, so long as it quarantined itself, but it would have to stop even goods arriving without people, because the rats and fleas might be in the wagons of woolens etc.

Tigertim
30-06-19, 15:41
The undoing of the native Britons in their battle against the Saxons, no coincidence the tide turned after 544 AD starting with the loss of Bath , Cirencester and Gloucester in 577 AD.