Posted on 10/24/2015 6:14:01 PM PDT by SunkenCiv
Y. pestis was the notorious culprit behind the sixth century's Plague of Justinian, the Black Death, which killed 30%-50% of the European population in the mid-1300s, and the Third Pandemic, which emerged in China in the 1850s. Earlier putative plagues, such as the Plague of Athens nearly 2,500 years ago and the second century's Antonine Plague, have been linked to the decline of Classical Greece and the undermining of the Roman army. However, it has been unclear whether Y. pestis could have been responsible for these early epidemics because direct molecular evidence for this bacterium has not been obtained from skeletal material older than 1,500 years...
To answer this question, the researchers screened 89 billion raw DNA sequence reads obtained from the teeth of 101 Bronze Age individuals from Europe and Asia. These teeth were obtained from various museums and archaeological excavations. They discovered Y. pestis DNA in seven of these individuals, whose teeth were dated between 2794 BC and 951 BC (early Iron Age). Evolutionary analysis revealed that the most recent common ancestor of all known Y. pestis strains is 5,783 years old--thousands of years older than previous estimates.
Moreover, Y. pestis genomes from the Bronze Age lacked a gene called Yersinia murine toxin (ymt), which is known to protect the pathogen inside the flea gut and thereby enable the spread of plague to humans via an insect vector. However, this gene was present in the Y. pestis genome from the Iron Age individual, suggesting that plague became transmissible by fleas between approximately 3,700 and 3,000 years ago. This new finding conflicts with previous studies suggesting that the ymt gene was acquired early in Y. pestis evolution due to its importance in the pathogen's life cycle.
(Excerpt) Read more at eurekalert.org ...
Interesting. It looks like they’ve established that the Plague of Athens and the Antonine Plague could have been Y. pestis, because the pathogen existed then. However, there’s no specific evidence that it actually was.
I think a water-borne infection is far more likely for the Plague of Athens, given that it was triggered by the crowding in the city during the invasion of Attica.
I’m interested in why some people have immunity to the disease and live to pass on their genes.
Several years ago I attended a lecture by an anthropologist who had been doing excavations on the North Slope of Alaska for several years. He once unearthed the skeleton of an adolescent male whose remains carbon-dated at 14,000 years. He had evidence of tuberculosis in his joints.
There are not many “new” diseases, are there?
People can be infected, survive the disease, and then pass on their genes. However, that doesn’t pass immunity, any more than a vaccinated parent passes immunity to measles to his or her child.
A survivor might have a genetic advantage that enabled his survival. On the other hand, disease outbreaks were episodic. A person might reach adulthood without exposure, which means that he reproduced without reference to any disease-resistant factors.
Many of these survivors had exposure to less than lethal variations of the infectious disease. They developed antibodies but I don’t know if those can be passed on genetically. What could be passed on are vigorous immune systems.
The age group who died most frequently during the influenza pandemic of 1918-19 was 20-40. The theory is that the virus had infected older people in previous years so they had some immunity after it mutated into a virulent strain. I don’t know if there is any explanation for the survival of many children. There were villages in Alaska where all of the adults died leaving only the children behind. The village of Eklutna outside of Anchorage started out as an orphanage for these kids in the early 1920’s. There was a similar orphanage outside of Nome.
They had liberals even back then?
Black Death Mutant Gene Resists AIDS, Say Scientists (Virus)
http://www.freerepublic.com/focus/news/1314116/posts?page=45#45
I had always thought that there was one Black Plague and that was it. In my genealogy research, I was lucky enough to discover a treasure trove of letters written by an ancestor between 1588-1595. By his letters, the plague broke out in London every summer. It was very ho-hum, “Oh do tell mum I’ll be coming out to the country, the plague is running thick here and bodies are stacked like cord wood in the streets...”
The Black Plague entered (well, re-entered) Europe in the 14th century; outbreaks continued from time to time right up into Tudor times (Shakespeare managed to survive his toddler years, perhaps by having been kept indoors, the Pestilence took a lot of people in Stratford).
Yes, and on further research, I learned that the main family estate was on land near a village in Oxfordshire that had been completely decimated by plague around 1490. Only 10 percent of the population survived and they had all moved away. Which I guess was good for my peeps, as they moved in around 1570 and built a pretty large manor house.
If you read descriptions of the plague from the 1500s and 1600s....there were people who would go through the start-up symptoms, and survive. A lot of these folks ended up as caretakers or body-handlers for disposing of the dead. Oddly, as the plague would come around about every twenty years....these people were pretty much ‘insulated’ and didn’t have nothing to worry about.
but too often news articles go in for ‘sexy’ diseases like plague or ebola to get headlines.
as for plague...I always thought the epidemic with “hemorrhoids” that affected the Philistines when they stole the ark of the covenant was plague.
and one epidemic that depopulated Mexico in the 1500s was not brought by the Spanish, but a hemorrhagic virus that had struck there in an epidemic before Columbus...
Add to my previous post....Ebola is a hemorrhagic virus, but not the only one, and it was’t in Mexico...
I thought I'd read that.
The Southwest and Mexico have a number of native hemorrhagic viruses; this is sometimes overlooked in the rush to blame Europeans for every epidemic.
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