# Black Death - causes?



## Brian G Turner

Here's one especially for scifimoth, because I;d be especially interested on her take on this issues.

Essentially, the Bubonic Plague - long since blamed on the pandemic that wiped out something towards a full third of the population of Europe - is now not so assuredly the cause.

I've been comnig across various questions in the science press, where basic assumptions about the disease - not least what the actual culprit was - have been raised.

Here's one of the more recent articles:



> http://www.newscientist.com/news/news.jsp?id=ns99994149
> 
> *Case reopens on Black Death cause*
> 
> Fresh controversy has broken out over the cause of the Black Death that killed up to half the people in Europe in 1348 and circulated for centuries after that.
> 
> For a century the blame has rested with the bubonic plague bacterium _Yersinia pestis_, which is carried by rats and fleas. But the most ambitious effort yet to find traces of _Yersinia_ in the remains of Black Death victims has failed, and the researchers involved argue that a previous study that did report finding _Yersinia_ was flawed.
> 
> "We cannot rule out _Yersinia_ as the cause of the Black Death," says Alan Cooper, head of the Ancient Biomolecules Centre at Oxford University, UK, whose team did the latest work. "But right now there is no molecular evidence for it."
> 
> The dispute over what caused the Black Death is more than just a historical concern. _Yersinia_ still infects people in the tropics and there are fears that it might be used as a bioweapon, unleashing another "Black Death". The Soviet Union, for example, reportedly prepared 1500 tonnes of it a year for military use. Such fears have prompted much research.
> 
> Yet, a detailed analysis of historical records led Susan Scott and Chris Duncan of the University of Liverpool, UK, among others, to conclude that _Yersinia_ was not the cause of the Black Death (*New Scientist* print edition, 24 November 2001). They think it might have been a haemorrhagic virus that caused massive bleeding, like Ebola.
> 
> 
> *Unique DNA sequences*
> 
> 
> In 2000, Didier Raoult and colleagues at the University of the Mediterranean in Marseille, France, claimed to have settled the matter by using PCR to amplify fragments of DNA extracted from the teeth of three 14th-century skeletons from nearby Montpellier. These sequences included some unique to _Yersinia_, they reported.
> 
> Scott and others argued that it was not even clear if the skeletons were from people who died from the Black Death. But in June 2003, Raoult dismissed such criticism as "unsubstantiated speculation".
> 
> Now Cooper and his colleagues have analysed 121 teeth from 66 skeletons found in five mass graves, including one in East Smithfield in London, UK, dug for Black Death victims in 1349. They also looked at suspected plague pits at Spitalfields in London, Vodroffsgaard in Copenhagen, Denmark, and Angers and Verdun in France.
> 
> Not one tooth harboured identifiable _Yersinia_ DNA, the team will tell this week's meeting of the British Society for General Microbiology in Manchester, UK. The team used primers - DNA fragments that act as probes in the PCR test to pick up specific sequences that were unique to _Yersinia_, but found nothing.
> 
> "And when we used the same primers the French used," Cooper told *New Scientist*, "we detected a lot of different bacteria, but none of the sequences were from _Yersinia_."
> 
> *Splitting and scraping*
> 
> Raoult is adamant that his team avoided contamination. But the latest study reveals how easy it can be. Splitting teeth and scraping out the inside, as the French group did, contaminated them with bacteria, Cooper's team found. After one lab did a control test with modern _Yersinia_ DNA, it got a positive result from a tooth - only to find it was contamination by the modern DNA.
> 
> What is more, nearly all the French samples tested positive - a suspiciously high survival rate for DNA in Montpellier's warm climate, Cooper believes. Together with the non-specificity of the primers, he thinks this makes it unlikely the French detected ancient _Yersinia_ DNA.
> 
> Cooper's team did find human mitochondrial DNA in the teeth, proving that DNA could survive there. But not finding _Yersinia_ DNA does not prove that the bacterium did not kill these people the infection might not have penetrated teeth.
> 
> "If I can get some soft tissue from the plague, I'll look again," he says. In Finland, for example, there may be victims buried in permafrost.


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## scifimoth

....very interesting. Of course it is very hard to tell what type of disease ran rampant in times gone by. People always think that the plague was the worst ever, but actually things like small pox and cholera caused as much devastation as yersinia pestis. Smallpox has been implicated in wiping out civilazations.
If it was not the plague that decimated the population back then I would say smallpox is a possibility. The whole idea about it being a hemorragic fever is interesting, but things like ebola need people in close contact in order to be able to keep running or the virus burns out as it kills of all available victims too quickly before reaching a new pool to feed on. Add to that that a victim of somthing like ebola is unable to travel far within the space of just a few days after breaking with the disease makes a fast burning virus like that an unlikely suspect in my eyes.
Of course I am not convinced that they can rule out yersinia pestis as completely as they might think...some illnesses are very picky about their target tissues and I am not convinced teeth would be a likely place to find remains of that type of lifeform.


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## Brian G Turner

Thanks for that - very interesting appraisal. 

I did wonder about the teeth issue as well - but I guess the article is as much a parry against a single earlier study, rather than a direct attempt to adderss the issue of sole cause for the Black Death.


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## dwndrgn

This is exactly why I have a lot of difficulty reading some scientific articles.  Quite often they say absolutely nothing.  Basically, the new study couldn't substantiate or knock down the earlier study (even though they created a little more doubt about the earlier methods used) and they didn't discover anything of their own either.  

In the last paragraph one stated that if they could find soft tissue they would use that for research.  Seems to me that they should have gone looking for that in the first place.  Sorry, am I just a little peevish today?

I agree with scifimoth regarding the hemorragic fever theory.  According to all that I have read regarding the time period, travel was a long a difficult process, yet the disease was easily spread - which seems to indicate that whatever disease is the culprit, its contagion period is almost immediate, the germinating period is quick and its death rate is slow.  In other words, travelers could come by, catch the *bug* and move on and live to pass it on to others.  This sounds nothing at all like Ebola.  Much more like AIDS.  In fact, it very well could have been some sort of immune system break down that allowed the people to die of the most prevalent virus/bacteria.  Heck, for all we know it was due to Mad Cow Disease!


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## Brian G Turner

You're right to be peevish - in this case it's perhaps more an issue of the internal politics of a particular discipline - but some of the research I read of in New Scientist simply makes me despair! The flaws of the testing method and the limitations of the conclusions are often obvious with a little common sense, but not to the researchers themselves. 

I have a particular beef with the more recent NASA declarations of water on Mars - hence why I have a thread dedicated to pasting articles on the topic. My accusation from the beginning is that NASA sexed up the claims of water on the red planet, so I intend to follow the progress of research from other groups on the subject.

Still, scientific method itself it's a very important way of collating "knowledge", and although the smaller pieces of the scientific jigsaw may present their own frustrations, how they actually all contribute to an overall picture is quite imicable.

Unfortunately, it also creates sometimes too powerful paradigms - but that's another story completely.


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## littlemissattitude

dwndrgn...I just said pretty much the same thing about science reporting over in the thread on villages and war.  My frustration, though, is in the translation from the report as actually written by the researchers to the digested version written by the reporter for the general public's consumption.  Often what is reported is not exactly what the actual research says.  So, I always read science reports in the popular press with a healthy skepticism.


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## Brian G Turner

Absolutely - who hasn;t seen the reports one week of how drinking tea prevents cancer - only to read the following week that drinking coffee prevent cancer.

One of the absolute Achilles heels is statistics - they are sooo easy to manipulate and spin towards a certain narrow interpretation - as any politician will evidence.

Btw - apologies, *dwndrgn*, if I was patronising you - I was making a general point, as much as anything.


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## littlemissattitude

> One of the absolute Achilles heels is statistics - they are sooo easy to manipulate and spin towards a certain narrow interpretation - as any politician will evidence.


Well, as they say, there are lies, damned lies, and statistics.  Kind of makes the point well, I think.


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## Brian G Turner

I am definitely going to have to remember that quote.


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## andyn

Not sure about the microbe, but the black death that swept through Europe was caused by the Mongol hordes. They were the first to use a crude form of biological warfare. They use to catapult the rottening corpses of those who had been killed into cities they were besieging. Refugees fleeing by sea,from this onslaught in what is now modern Russia brought into Northern Europe. Hence the myth it was brought in by the rats coming of the boats as they docked. Most likely the spread was caused by contact with infected human beings. Medieval Cities were not known for their  sanitation.


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## sarakoth

andyn said:


> Not sure about the microbe, but the black death that swept through Europe was caused by the Mongol hordes. They were the first to use a crude form of biological warfare. They use to catapult the rottening corpses of those who had been killed into cities they were besieging. Refugees fleeing by sea,from this onslaught in what is now modern Russia brought into Northern Europe. Hence the myth it was brought in by the rats coming of the boats as they docked. Most likely the spread was caused by contact with infected human beings. Medieval Cities were not known for their sanitation.


 
In my history class, the teacher taught me that the plague originated in China, killing over 30 million people. It was brought to Europe by traders.


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## PTeppic

I saw something on the TV a year or two back about this. It basically went through all the "known" symptoms of the medieval Black Death and compared them to the symptoms of bubonic plague (which still gets half a dozen cases a year in the USA, for example) and guess what - neither list matches the other. I think they said on that show that one of the haeomoraghics was the most likely.


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## Hypes

Necrophilia is bad!



> Hence the myth it was brought in by the rats coming of the boats as they docked. Most likely the spread was caused by contact with infected human beings.



Why is it a myth? It sounds a lot more realistic that rats were the initial carriers of the disease, rather than fleeing refugees - how would they even survive long enough?


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## sarakoth

PTeppic said:


> I saw something on the TV a year or two back about this. It basically went through all the "known" symptoms of the medieval Black Death and compared them to the symptoms of bubonic plague (which still gets half a dozen cases a year in the USA, for example) and guess what - neither list matches the other. I think they said on that show that one of the haeomoraghics was the most likely.


 
I don't know what you were watching but modern historians and scientists pretty much all agree that the Black Death was caused by bubonic plague.


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## PTeppic

Isn't that the point of this thread - that whilst there has been widespread assumption that this was the case, a number of sources are beginning to question that assumption...


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## Sephiroth

I saw a programme about this, too, a while back.  One suggestion made was that at the time of the Black Death, the Black Rat population outside of the major cities was not sufficient to facilitate the spread of the disease across vast, open tracts of countryside.  They seemed to be suggesting that there weren't other susceptible rodents (or certainly in enough density) that would have performed the same function.  IIRC, speculations were that the disease might have been airborne, or else due to some widespread contamination of wheat.  

Unfortunately, it has been ages since I saw it, and my memory is letting me down.


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## andyn

The simple fact no one truly knows why or how it spread. The rats thing comes down to the chroniclers of the time.


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## Wiglaf

On a TV show I saw once they even speculated about anthrax (dark spots). It seemed a stab in the dark though. However, rats do seem unlikely. As for bubonic plague vs. ebola type virus, whatever it was seems to have been mutating as it spread. It could have been a mutated offshoot of bubonic plague. The certainty that it was bubonic plague has been dispelled, but it is still a remote possibility. We just have to wait for more info.
Its effects on society are more well documented however. You can still use that information for ideas on how an epidemic would affect your SF/F world.

Sorry, I can't give my sources. I need 15 posts before I can provide links.


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## clovis-man

She didn't go into any speculation about causes, but Barbara Tuchman wrote a very detailed book which gives great information about the effects of the plague and the efforts to contain it in "A Distant Mirror".

Regards,

Jim


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## Happy Joe

I believe that at least some of the Plagues were bubonic in origin. Locally (to my home) it is found in prairie dogs and ground squirrels. Rats and mice (and other small animals) are also known to be potential carriers (via fleas). 
One factor that most folks do not know is that bubonic plague as carried by rodents (transferred via flea bite (other insects can also carry it)) is not the most infectious form (it needs an insect bite to transmit it); in a few percent of human cases it causes lesions in the lungs. 
When this happens (pneumonic plague) it is very highly infectious (very easily transmitted by coughing) and has a much higher fatality rate (virtually 100% if untreated).  When transmitted in its pneumonic form it continues to propagate in pneumonic form.  One person coughs then another and another...

I personally like Daniel Defoe's; "A Journal of the Plague Year, written by a citizen who continued all the while in London"
A Journal of the Plague Year, written by a citizen who continued all the while i - Project Gutenberg
written in the 1600's, it provides a fair snapshot of what occurred (and to some extent what could be expected in a modern pandemic). Remember this was written in a time of very limited medical knowlege.

Enjoy!


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## Bentony

Unfortunatley for all the plague deniers there is extremely good DNA evidence to show that the plague was caused by Yersina Pestis: i.e. black death most likely in a combination of Bubonic and Pneumonic phases.  It came in from the  Mongol Stepps due to various factors including the expansion of the Mongol empire, the development of trade links and the growth of trade with the east, thus breaking down the isolation of the area and allowing the disease to spread.  That said there were a myriad of factors that allowed it to explode the way it did in Europe at the time. In this way it is similar to the fact that it took very specific factors in the 1970's and 80's to allow the spread of HIV - including truck routes and migrant populations displaced by wars.
There is an excellent book by John Kelly called "The Great Mortality, a history of the black death" that covers the topic very well, as well as addressing all the "alternatives" to Y Pestis.
And yes, it's still out there.


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## Jardax

One of the Black Death theories mention lowered population of cats - a natural enemies of rats.

Cats had a difficult times during middle age. Cats were very often killed because fanatics trusted they are connected to devil, sorcery etc.... So human stupidity can be the real Plague reason.


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## Null_Zone

andyn said:


> The simple fact no one truly knows why or how it spread. The rats thing comes down to the chroniclers of the time.


 
Definately.

Iceland for example had cases of the plague but had no rat population.


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## Happy Joe

If not rats how about sailors with fleas?
(or even mice?)

I believe the transmission vectors are well documented fleas transfer the disease to an intermediate carrier (around here its typically ground squirrels or prairie dogs that carry it, rats are convenient, but not necessary) or to man, if lesions develop in people's lungs they cough and it spreads rapidly producing epidemic or pandemic disease and death.

Enjoy!


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## J Riff

That far back in time, history is utterly unreliable.
Why are there no details of this huge event that affected millions?
How did the secret of the building of the pyramids ever dissapear? 
Doesn't make sense. 
One thing tho- once it got started, whatever disease or diseases it really was - no one would do anything to stop it and it would spread and mutate freely until it had run it's course.
 There's a lot of questions about the masses who died during the second war in Europe, let alone hundreds of years ago.


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## Karn Maeshalanadae

Actually, the most widely accepted theory on what caused the Bubonic plague was that it was spread by rat fleas.


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## Starbeast

*Plagues can happen at any time, however we have more resources to combat against them in modern times.*​


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