Posted on 01/21/2023 7:16:22 AM PST by SunkenCiv
One of the most commonly recited facts about plague in Europe was that it was spread by rats. In some parts of the world, the bacterium that causes plague, Yersinia pestis, maintains a long-term presence in wild rodents and their fleas. This is called an animal "reservoir".
While plague begins in rodents, it sometimes spills over to humans. Europe may have once hosted animal reservoirs that sparked plague pandemics. But plague could have also been repeatedly reintroduced from Asia. Which of these scenarios was present remains a topic of scientific controversy.
Our recent research, published in the Proceedings of the National Academy of Sciences (PNAS), has shown that environmental conditions in Europe would have prevented plague from surviving in persistent, long-term animal reservoirs. How, then, did plague persevere in Europe for so long?
Our study offers two possibilities. One, the plague was being reintroduced from Asian reservoirs. Second, there could have been short- or medium-term temporary reservoirs in Europe. In addition, the two scenarios might have been mutually supportive.
However, the rapid spread of the Black Death and subsequent outbreaks of the next few centuries also suggest slow-moving rats may not have played the critical role in transmitting the disease that is often portrayed.
(Excerpt) Read more at phys.org ...
Rome and Florence supposedly had 50 to 75% mortality rates, while Milan had a 15% mortality rate. The reason why was that Milan leaders sealed and bricked up affected households basically leaving them to die.
Have no idea how accurate the history is.
That’s a prayerie dog. Yep, he looks like he is praying!
Cholecalciferol is Vitamin D3. We are helping rats build strong bones and get through the long, dreary winter days?
“But plague could have also been repeatedly reintroduced from Asia.”
Yes, and on a contemporary note, one of the key vectors for the bubonic plague entering Europe was through what is today Ukraine/Crimea, since trade goods from China would route through there to the Genoese trading posts for shipment to the Mediterranean.
The article is not saying that the plague was not spread by rats and fleas but that it is unlikely that it could have spread as quickly or for as long as it did exclusively by the rat/flea vector.
It suggest that the plague was spread by human to human contact and that the rats were a supplemental spreader.
This makes sense given at the time human fleas and lice were the norm. Everyone had them.
What I would like to have more info on is the idea that the soil conditions in Europe would not support plague bacteria survival.
“slow-moving rats may not have played the critical role...”
Rats do not move slow when we are transporting them on ships...
Well good. Now we know what to do with all the new rat poison we bought that doesn't work. It won't go to waste. We can just munch on it ourselves to help protect us from Covid...
“My guess is that people in the middle ages were likely better at catching and killing rats than their modern counterparts...”
They bred plenty of animals to catch rats, both house cats and various dog breeds. But I believe those were mainly used to keep rats from eating all the agricultural production. I doubt there was much attempt at all to stop rats in the cities.
There is a good book called “Justinians Flea” (cannot remember the author) regarding the emergence of the plague in Constantinople. The premise is that rats and their fleas arrived in Constantinople on grain ships from Egypt. The plague decimated the population of Constantinople. Rats being opportunistic hitchhiked on ships and other transportation to all corners of Europe creating the pandemic we call the “Black Death”.
That might just be the case!
“...or are you suggesting immunological naievete in Europe”
Since the vast majority of the population of Europe didn’t come from Europe, but from Eurasia, that’s highly unlikely.
There was a study about 10 or so years ago analyzing the speed of plague, documented by village church records, across England in 1348 (generally accepted as the first year of Black Death).
The conclusion of the study was that rats can’t move that fast so maybe Yersenia Pestis (the bacteria) was not responsible for plague. Suggestions of multiple years of famine arose as having weakened the populace and making people susceptible to random virus events.
When this happened, mass graves in England were opened and DNA samples were taken from the bodies. All were found to have Y. Pestis DNA residual, added to all of the documented stories of the time about symptoms that match up well.
So this article today is attempting to reconcile the two items of research. Yes, Y. Pestis, but maybe not via rats, they want to say.
The rat concept arose because of how they were everywhere and how port cities got hit first.
City to city transport could be other animals with fleas (horses?), but to get everywhere inside a city so fast, rats still seem like a good explanation.
Note there was a plague outbreak in Chinatown of San Francisco in 1900. Smaller population then, of course. 100+ cases and all but 2 died.
The governor of California tried to deny anything of the sort was happening and shut off mitigation rules like quarantine and other measures taken. Ships from Asia were flagged as possible plague carriers. This was bad for business and his reasons for shutting down prevention were economic damage to the state. There was an election in 1902 and he lost. The winner then spent big money on mitigation.
Then in 1906 the great San Fran earthquake burned up most of the city. In 1907 plague hit the city again during reconstruction, though outside Chinatown and in suburbs, including across the bay in Oakland.
Another 150+ infected, 70+ deaths — a lower rate. All were European this time rather than Asian. There had been articles in 1900 saying California was plague immune because Asians (many plague outbreaks in Asia 1895+) ate a rice rich diet and Euro descent Americans ate meat and this was claimed decisive. It is generally likely that reservoirs in the US now in Colorado Utah Arizona and New Mexico rodents were established in squirrels that travelled from California in the early 1900s.
This is the first I’ve heard that rats are slow moving in their reproduction and spreading out. If the food is there THEY are there.
The best mouse, mole and rat killer we ever had was our miniature dachshund who was bred to be a sporting dog in Alabama. He used to come back with a "gift" for us far more often than any cat that we have ever owned. Since he got old and died we have had a terrible problem with moles.
Cats (and some dogs) ate the rats, got fleas from the rats, spread it through the households.
Don’t know if mites on birds carry the plague, but if so, that might explain a more rapid dispersal of the plague?
It is amazing how fast disease spread in the early years of civilization with primitive shipping and overland caravans.
I saw a video a while back about the spread of the Spanish Flu from Europe back to the US and Canada via returning WW I soldiers. They came home on ships and immediately boarded trains to get to their homes throughout the US and Canada. The spread was incredibly fast. The first transcontinental railroad in North America was completed only 50 years earlier and very quickly became a vector for fast disease transmission.
A few years ago I had a rat problem. I bought those little round poison balls. After they went through about $50 worth I asked the guy at the counter WTH. He said they don't eat it on-site. They take it with them and stash it.
So, I bought the solid type. Look like a long cube with a hole in the middle. I mounted a 12" stiff wire on a board. Slid about 5 of those cubes on. Now they had to eat it there. No carry out. Solved the problem pretty quickly.
It was called “The Spanish Flu”, because Spain was the only country at the time that didn’t censor reports on the Flu.
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