The Black Death: Plague that killed millions is able to rise from the dead

Black rats are also implicated in both outbreaks, which took place 800 years apart

Science Editor

Two of the most devastating outbreaks of plague in history, each of which killed more than half the population of Europe, were caused by different strains of the same infectious agent, a study has revealed.

The Justinian Plague of the 6th Century AD, which is credited with leading to the final demise of the Roman Empire, and the Black Death of the 14th Century, were both caused by the independent emergence of the plague bacterium from its natural host species, the black rat, scientists said.

An analysis of bacterial DNA extracted from the teeth of two plague victims who died in the early 6th Century in present-day Bavaria, Germany, has shown that they were infected with the bacterium Yersinia pestis, the same plague agent known to have caused the Black Death 800 years later.

However, a detailed comparison of the bacteria’s DNA sequences has revealed that the two outbreaks were quite independent of one another. Each pandemic was the result of different Yersinia strains, indicating the independent emergence from the black rat on two separate occasions, the researchers said.

Although the strain behind the Justinian Plague died out completely, the strain that caused the Black Death probably re-emerged a few centuries later to cause the so-called Third Plague pandemic which began in the mid-19th Century in China and went on to kill about 12 million people in China and India alone, although it did not travel to Europe.

The scientists behind the study, published in the journal The Lancet Infectious Diseases, warned that the findings suggest there is a possibility of another pandemic strain of plague to emerge from the existing reservoir of Yersinia bacteria living in the current rodent population.

“The key point here is that this bug can re-emerge in new forms in humans and can have a tremendous impact on human mortality. It’s done it three times in the past and we should be monitoring it for the future,” said Hendrik Poinar, director of the Ancient DNA Centre at Canada’s McMaster University in Hamilton, Ontario.

The Justinian Plague, named after the Roman emperor who died of it, probably began in Asia but first came to prominence when it swept through the eastern Roman capital of Constantinople. It killed at least 50 million people, almost half the global population at the time, and is generally regarded as the first documented outbreak of bubonic plague.

The DNA analysis of the full Yersinia genome extracted from the two Bavarian plague skeletons, however, has shown that the pandemic died out completely within a couple of centuries without leaving any bacterial descendants, Dr Poinar said.

“The research is both fascinating and perplexing. It generates new questions which need to be explored, for example why did this pandemic, which killed somewhere between 50 and 100 million people die out?” Dr Poinar said.

The scientists extracted overlapping fragments of Yersinia DNA from the teeth of the two plague victims and were able to build the entire genome of 4.6 million “base pairs” – the individual letters of the genetic alphabet that comprise the bacterium’s genetic code.

“We know the bacterium Y. pestis has jumped from rodents into humans throughout history and rodent reservoirs of plague still exist today in many parts of the world,” said Dave Wagner of Northern Arizona University in Flagstaff, Arizona, the lead author of the study.

“If the Justinian plague could erupt in the human population, cause a massive pandemic, and then die out, it suggests it could happen again. Fortunately, we now have antibiotics that could be used to effectively treat plague, which lessens the chances of another large scale human pandemic,” Dr Wagner said.

Long periods of warm, wet weather preceded both the Justinian Plague and the Black Death, which was thought to have resulted in an explosion in the rat population. Scientists suspect that plague outbreaks eventually die out as people develop a natural immunity to the bacteria.

“Another possibility is that changes in the climate became less suitable for the plague bacterium to survive in the wild,” Dr Wagner said.

Start your day with The Independent, sign up for daily news emails
Life and Style
love + sex
Life and Style
Tikka Masala has been overtaken by Jalfrezi as the nation's most popular curry
food + drink
News
people
Voices
A propaganda video shows Isis forces near Tikrit
voicesAdam Walker: The Koran has violent passages, but it also has others that explicitly tells us how to interpret them
ebooks
ebooksA special investigation by Andy McSmith
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: 2nd Line IT Support Technician

£26000 - £29000 per annum: Recruitment Genius: An opportunity has arisen for a...

Recruitment Genius: Business Manager

£25000 - £35000 per annum: Recruitment Genius: This highly successful business...

Ashdown Group: HR Advisor - Bedfordshire - £30,000 + Excellent package

£28000 - £30000 per annum + Bonus, Pension, 25days hol, PHC +: Ashdown Group: ...

Recruitment Genius: Sales Administrator - Japanese Speaking

£16000 - £25000 per annum: Recruitment Genius: If you are fluent in Japanese a...

Day In a Page

Syrian conflict is the world's first 'climate change war', say scientists, but it won't be the last one

Climate change key in Syrian conflict

And it will trigger more war in future
How I outwitted the Gestapo

How I outwitted the Gestapo

My life as a Jew in wartime Berlin
The nation's favourite animal revealed

The nation's favourite animal revealed

Women like cuddly creatures whilst men like creepy-crawlies
Is this the way to get young people to vote?

Getting young people to vote

From #VOTESELFISH to Bite the Ballot
Poldark star Heida Reed: 'I don't think a single bodice gets ripped'

Poldark star Heida Reed

'I don't think a single bodice gets ripped'
The difference between America and Israel? There isn’t one

The difference between America and Israel? There isn’t one

Netanyahu knows he can get away with anything in America, says Robert Fisk
Families clubbing together to build their own affordable accommodation

Do It Yourself approach to securing a new house

Community land trusts marking a new trend for taking the initiative away from developers
Head of WWF UK: We didn’t send Cameron to the Arctic to see green ideas freeze

David Nussbaum: We didn’t send Cameron to the Arctic to see green ideas freeze

The head of WWF UK remains sanguine despite the Government’s failure to live up to its pledges on the environment
Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Set in a mythologised 5th-century Britain, ‘The Buried Giant’ is a strange beast
With money, corruption and drugs, this monk fears Buddhism in Thailand is a ‘poisoned fruit’

Money, corruption and drugs

The monk who fears Buddhism in Thailand is a ‘poisoned fruit’
America's first slavery museum established at Django Unchained plantation - 150 years after slavery outlawed

150 years after it was outlawed...

... America's first slavery museum is established in Louisiana
Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

The first 'American Idol' winner on how she manages to remain her own woman – Jane Austen fascination and all
Tony Oursler on exploring our uneasy relationship with technology with his new show

You won't believe your eyes

Tony Oursler's new show explores our uneasy relationship with technology. He's one of a growing number of artists with that preoccupation
Ian Herbert: Peter Moores must go. He should never have been brought back to fail again

Moores must go. He should never have been brought back to fail again

The England coach leaves players to find solutions - which makes you wonder where he adds value, says Ian Herbert
War with Isis: Fears that the looming battle for Mosul will unleash 'a million refugees'

The battle for Mosul will unleash 'a million refugees'

Aid agencies prepare for vast exodus following planned Iraqi offensive against the Isis-held city, reports Patrick Cockburn