Cause of the big plague epidemic of Middle Ages identified

Oct 11, 2010
Geographical position of the five archaeological sites investigated. Green dots indicate the sites. Also indicated are two likely independent infection routes (black and red dotted arrows) for the spread of the Black Death (1347-1353) after Benedictow. ©: PLoS Pathogens

(PhysOrg.com) -- The 'Black Death' was caused by at least two previously unknown types of Yersinia pestis bacteria.

The latest tests conducted by anthropologists at the Johannes Gutenberg University Mainz (JGU) have proven that the Yersinia pestis was indeed the causative agent behind the "Black Death" that raged across Europe in the Middle Ages. The cause of the epidemic has always remained highly controversial and other pathogens were often named as possible causes, in particular for the northern European regions. Using DNA and protein analyses from skeletons of plague victims, an international team led by the scientists from Mainz has now conclusively shown that Yersinia pestis was responsible for the Black Death in the 14th century and the subsequent epidemics that continued to erupt throughout the European continent for the next 400 years. The tests conducted on genetic material from mass graves in five countries also identified at least two previously unknown types of Yersinia pestis that occurred as pathogens.

"Our findings indicate that the plague traveled to Europe over at least two channels, which then went their own individual ways," explains Dr. Barbara Bramanti from the Institute of Anthropology of Mainz University. The works, published in the open access journal PLoS Pathogens, now provide the necessary basis for conducting a detailed historical reconstruction of how this illness spread.

For a number of years, Barbara Bramanti has been researching major epidemics that were rampant throughout Europe and their possible selective consequences as part of a project funded by the German Research Foundation (DFG). For the recently published work, 76 human skeletons were examined from suspected mass graves for plague victims in England, France, Germany, Italy, and the Netherlands. While other infections such as can be easily identified long after death by the deformed bones, the problem faced in the search for plague victims lies in the fact that the illness can lead to death within just a few days and leaves no visible traces. With luck, DNA of the pathogen may still be present for many years in the dental pulp or traces of proteins in the bones. Even then it is difficult to detect, and may be distorted through possible contamination. The team led by Bramanti found their results by analyzing old , also known as ancient DNA (aDNA): Ten specimens from France, England, and the Netherlands showed a Yersinia pestis-specific gene. Because the samples from Parma, Italy and Augsburg, Germany gave no results, they were subjected to another method known as immunochromatography (similar to the method used in home pregnancy tests for example), this time with success.

Once the infection with Yersinia pestis had been conclusively proven, Stephanie Hänsch and Barbara Bramanti used an analysis of around 20 markers to test if one of the known bacteria types "orientalis" or "medievalis" was present. But neither of these two types was found. Instead, two unknown forms were identified, which are older and differ from the modern pathogens found in Africa, America, the Middle East, and the former Soviet Union regions. One of these two types, which are thought to have contributed significantly to the catastrophic course of the plague in the 14th century, most probably no longer exists today. The other appears to have similarities with types that were recently isolated in Asia.

In their reconstruction, Hänsch and Bramanti show an infection path that runs from the initial transportation of the pathogen from Asia to Marseille in November 1347, through western France to northern France and over to England. Because a different type of Yersinia pestis was found in Bergen op Zoom in the Netherlands, the two scientists believe that the South of the Netherlands was not directly infected from England or France, but rather from the North. This would indicate another infection route, which ran from Norway via Friesland and down to the Netherlands. Further investigations are required to uncover the complete route of the epidemic. "The history of this pandemic," stated Hänsch, "is much more complicated than we had previously thought."

Explore further: 40 states, district of columbia reporting respiratory virus that targets kids

More information: Haensch, S., Bianucci, R., et al. (2010) Distinct Clones of Yersinia pestis Caused the Black Death PLoS Pathog 6(10): e1001134. doi:10.1371/journal.ppat.1001134

Provided by Johannes Gutenberg University

4.8 /5 (26 votes)

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otto1932
1.2 / 5 (18) Oct 11, 2010
"The history of this pandemic," stated Hänsch, "is much more complicated than we had previously thought."
Yes but it could be explained much more simply by assuming that it was spread deliberately for the purpose of depopulating and thus pacifying Europe in preparation for the Renaissance and the invasion of the Americas.

Many profound mysteries- spread by fleas on rats, but out of flea-season; lack of dead rats in the streets as a precursor to human contageon; areas of the continent strangely untouched; etc.

One question- why were priests and monks infected at 40x the rate of the general pop? I cite a study from Penn state a decade or so ago. Could this be because the clergy was actively involved in distributing the plague in keeping with their mission as shepherds of the flock? As ye sow so shall ye reap. A time to sow and a time to reap etc.
-Cont.
otto1932
1.2 / 5 (17) Oct 11, 2010
This is not so outlandish when one considers how plague had been routinely used in siege warfare, as early as Athens in the peloponnesian wars; and against Indians in north America. The plague was introduced in europe at one point during a mongol siege of a genoan city on the Crimea, by lobbing infected bodies over the walls. People knew how to transport plague and how to use it against others effectively.

We could believe that 90% of mesoamericans died through the intentional spread of disease... not a far stretch. But the plague would have wreaked havoc on Europe if it had found it's way back from the Americas, an Inevitability. And so Europe was inoculated against it, and the recovering pops had as a result some immunity to it. The Americas were conquered and colonized in orderly fashion by people who were resistant to the contagions that were used against indigenes.
otto1932
1.2 / 5 (17) Oct 11, 2010
-Had this same Mechanism been used in the Justinian plague to prepare the roman empire for the conquest of Europe? Sun tzu had written on how to befoul water supplies and otherwise similarly infect the Enemy. And I'm sure he knew full well that the enduring Enemy of Stability and Progress is always the people. The people are the enemy of Rulers, a fact that brought them together and began Their Scheming.

Biowarfare is an ancient art. So is Shepherding.
mertzj
3.7 / 5 (3) Oct 11, 2010
Your smokin crack otto...
Mayday
2.3 / 5 (3) Oct 11, 2010
You know, I think I'm with otto. The conquest of the Americas was far too easy. Healthy, civilized, organized, determined societies defending familiar ground? Poof? I think there had to be more to it than meets the eye.
Simonsez
2.3 / 5 (3) Oct 11, 2010
@ otto

A well presented argument, logical and well thought out. It certainly makes sense to me and I have long surmised at least the conquering of the Americas by initial infections, as well as having read historical accounts of the Mongols using diseased bodies in warfare; this is the first time I have heard anyone suggest it of the plague.
jennifer_delmont
1 / 5 (1) Oct 11, 2010
This is the first time I read about the plague being compared to biowarfare. Could you possibly provide me with a few good links in support of your theory, Otto?
otto1932
1.2 / 5 (17) Oct 11, 2010
Per the Crimean siege of 1346:
"However, it is unlikely that the attack had a decisive role in the spread of plague to Europe."
http://www.cdc.go...0536.htm
-The article does show that plague was most likely used as a weapon even if it had little effect on the outcome.

As to the clergys involvement in the spread of it, one only need consider if the early Jesuits, who assassinated at least one pope and who were kicked out of various countries for their nefarious deeds; or the borgias, who were notorious for their corruption, could have participated in such a thing.

But the Scale and Purpose inherent in such a Campaign would imply a dedication to a Cause greater than even god- the need to conquer the entire world in order to prevent the destruction of civilization by those outside it's sphere of influence.
mn3m0n1x
1 / 5 (2) Oct 12, 2010
it wasn't the clergy man it was aliens
AtomThick
5 / 5 (6) Oct 12, 2010
One question- why were priests and monks infected at 40x the rate of the general pop? I cite a study from Penn state a decade or so ago. Could this be because the clergy was actively involved in distributing the plague in keeping with their mission as shepherds of the flock?


The answer could be simpler, the priests usually interact with 40x more people than a regular individual does, resulting in 40x more chances of getting infected therefore there's no need for a conspiracy theory here.
otto1932
1 / 5 (16) Oct 12, 2010
The answer could be simpler, the priests usually interact with 40x more people than a regular individual does, resulting in 40x more chances of getting infected therefore there's no need for a conspiracy theory here.
Yes, ministering to the sick and blackened with no concern for themselves. EXCEPT that, in the context of all the other anomalies, one can begin to suspect that the plague was distributed intentionally; and that the priesthood could have been doing this expressly BECAUSE they enjoyed free rein and typically had intimate contact with so many people.

The plague spread when fleas were typically not active. But the clergy lived and worked behind closed facilities with ample cool spaces where colonies could be kept in secret.

Again, plague had been used in war for millenia. People had to know far more about how to use it than we might suppose.
otto1932
1 / 5 (17) Oct 12, 2010
In fact, if this were actually being done, then the clergy were the only people who COULD have done it.

This all presupposes that the invasion and conquest of the Americas was Planned and Prepared for, instead of just accidentally happening as swiftly and decisively as it did, as Simonsez points out above.

It also assumes that the history books record not the truth but the propaganda meant to obscure it. So much of what happened during this period is unknown. So much of these cultures was obliterated in the name of god that we may never know what really happened to them, and Why.
MatthiasF
5 / 5 (2) Oct 17, 2010
Yes, ministering to the sick and blackened with no concern for themselves. EXCEPT that, in the context of all the other anomalies, one can begin to suspect that the plague was distributed intentionally; and that the priesthood could have been doing this expressly BECAUSE they enjoyed free rein and typically had intimate contact with so many people.


Occam's razor. Learn how to use it.
tony321
not rated yet Oct 19, 2010
Hey you forgot to blame God yet?