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Introduction to the plague

The world has suffered from many - COVID 19 was not the first, nor will it be the last.

The Black Death is probably the most famous pandemic in history. Between 1347 and 1351, this outbreak of bubonic plague killed millions of people across Europe, North Africa and the Middle East.

Over the following centuries, plague returned many times, with a particularly deadly outbreak in the British Isles in 1665 and 1666.

A woodcut showing townspeople fleeing to the countryside to escape the Bubonic Plague in England, 1630.Image source, ALAMY
Image caption,
A woodcut showing townspeople fleeing to the countryside to escape the Bubonic Plague in England, 1630.
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Video: The plague

How did a tiny bacteria lead to the deaths of millions of Europeans? In this video, learn about early pandemics and the impact of the plague.

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What caused the plague?

At the time, it was not known how the plague spread - some people believed that farm animals were responsible for the disease and slaughtered their livestock.

Religious leaders believed that the plague was sent as a punishment by God for the sinful nature of the people.

Others, such as the doctors of the time, believed that the air had been poisoned and that when an individual breathed in this poisonous air they were infected with the plague. They called this bad air .

Fleas carry diseases including the plague, caused by the bacterium Yersinia pestis.Image source, ALAMY
Image caption,
Fleas carry diseases including the plague, caused by the bacterium Yersinia pestis.

Modern research has found that the plague was caused by a known as Yersinia pestis.

This bacterium circulates amongst wild rodents, such as rats, and their fleas.

Yersinia pestis is spread when fleas drink the blood of infected rats. Once the infected rats die, the fleas move on to find a new host. An infected flea's bite passes the bacterium to their new host.

When the new host is a human, the bacteria enters human’s bloodstream and the infection causes plague.

Fleas carry diseases including the plague, caused by the bacterium Yersinia pestis.Image source, ALAMY
Image caption,
Fleas carry diseases including the plague, caused by the bacterium Yersinia pestis.

Where did the plague come from?

The ruins of a caravan stop on the old Silk Route in Kyrgyzstan.Image source, ALAMY
Image caption,
The ruins of a caravan stop on the old Silk Route in Kyrgyzstan. The Silk Routes were a network of tracks and trails that merchants used to trade clothes, spices, jewels, and other goods between China, India, and Western nations.

In 2022, researchers, including a team from the University of Stirling, tracked down the origins of the Black Death.

DNA samples taken from skeletons that had been buried in the north of modern-day Kyrgyzstan, Central Asia in the 1330s showed that they had been infected with the Yersinia pestis bacterium which causes plague. (Source: ).

Importantly, this region was criss-crossed by trading roads known as the Silk Route. These routes led from China all the way to the Mediterranean Sea.

From this small beginnings in a remote valley thousands of miles away, the Black Death would spread across Europe, eventually even arriving in Scotland.

The ruins of a caravan stop on the old Silk Route in Kyrgyzstan.Image source, ALAMY
Image caption,
The ruins of a caravan stop on the old Silk Route in Kyrgyzstan. The Silk Routes were a network of tracks and trails that merchants used to trade clothes, spices, jewels, and other goods between China, India, and Western nations.

How did the plague spread?

Trade helped to spread the plague.

Travellers on the Silk Route took the infection with them. Often ships would carry the black rats, taking them (and their fleas) to new cities and countries.

  • In 1346 the plague arrived in Europe and caused the deaths of millions of people.
  • By 1348, it had arrived in southern and western England.
  • In 1350, the plague arrived in Scotland – possibly as a result of a Scottish raid on England late in 1349.

Later outbreaks swept through Europe in the 1400s, and again in the 1600s

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Symptoms of the plague

The symptoms of bubonic and pneumonic plague.

The infection was actually three diseases:

  • Bubonic plague
  • Pneumonic plague
  • Septicemic plague

Bubonic plague

The most common form of plague is bubonic plague which affects the . Two to eight days after infection, a person will develop fever, aches and vomiting.

Painful swellings called buboes would appear in sweaty regions of the body (armpit, groin and thigh). It is these buboes that give bubonic plague its name.

Around 50 per cent, or half or all those infected would die from bubonic plague.

Pneumonic plague

Pneumonic plague affects the lungs. Its main symptoms are fever, aches and coughing, including coughing blood.

It is caused by breathing in bacteria coughed out by an infected person, or spread to the lungs through a person's own blood supply.

Pneumonic plague was less common but killed nearly everyone who suffered from it.

Septicemic plague

Septicemic plague affects the blood. As well as aches and fever, this form of infection could cause bleeding and organ failure.

Blood supply to some parts of the body could stop. This could cause some parts of the body, such as the fingers, toes or nose, to die, rot and turn black.

This is one possible explanation for why the plague later became known as the Black Death.

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Preventing the plague

Most people who became infected with plague died from it, so it was important to try and prevent it spreading. This was difficult because the cause of plague was not understood.

One method that did work was separating those who may have been infected from the rest of the population. This practice had been used from ancient times, featuring in the bible and writing from Ancient Greece.

In 1348, authorities in Venice in Italy brought in a rule that individuals or even whole ships coming from infected areas would have to wait for 40 days before coming into port. This was called quarantine. The word comes from the Italian quaranta giorni, which means forty days.

Quarantine is still used to this day, for example people infected with Covid-19 staying in isolation until they are free of infection.

Preventing the spread of the Plague: fires, killing cats and dogs, locking people in houses, searchers looking for the cause of death, banned public gatherings, smoking tobacco and coins in vinegar.

Evidence produced at the time of the Great Plague of 1665-66 gives us useful information about what people did to try and prevent the plague from spreading. Some actions taken by the government included:

  • Instructing fires to be lit in the street, so people could breathe in the smell of smoke, rather than the miasma believed to be causing the disease.

  • Cats and dogs were killed, as it was believed that they might spread the plague. It is estimated that 40,000 cats and 200,000 dogs were killed.

  • Plague victims were locked in their houses for 40 days and a red cross was painted on their door. Watchers were employed to make sure people didn’t leave.

  • Searchers had the job of entering the home of suspected plague victims to search for bodies, and removing them to be placed in plague burial pits.

  • Public gatherings were banned, and people were not allowed to travel from one town to another unless they had a certificate proving they didn’t have plague.

Some people took action on an individual basis to try and protect themselves from catching the disease:

  • Some people, particularly searchers, who were responsible for collecting the bodies of plague victims, decided to smoke tobacco. It was believed this would protect them against plague, which was completely incorrect.

  • Some people placed money in small pots of vinegar when paying for goods to avoid touching it directly from someone else.

What was the role of women during the plague?

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Medieval treatments for the plague

Various methods were used to try and cure an infected individual. Treatment depended on what people believed caused the plague.

Punishment from God

Flagellants in the Dutch town of Doornik in 1349 whipping themselves with ropes in the hope that it would persuade God to free the world from the Black Death.Image source, ALAMY
Image caption,
Flagellants in the Dutch town of Doornik in 1349 whipping themselves with ropes in the hope that it would persuade God to free the world from the Black Death.

Those who believed that the plague had been sent by God as a punishment turned to the Church for guidance and help.

The Church was ordered by King Edward III of England to hold a service every day so people could attend, pray for God’s forgiveness and light candles as an offering to God.

In 1456, during another outbreak of plague, James II, King of Scots, passed a law that allowed priests to break the strict rules so that they could continue to conduct religious services to pray to God for deliverance from the plague.

Some people went without food for a time to show that they were sorry for their sins - this is known as fasting.

Many individuals went on journeys known as pilgrimages. They would journey to places of religious significance, such as the tombs of saints, and prayers would be offered to God.

Others, such as the flagellants, would harm themselves in public by whipping their own backs as a sign of how sorry they were for their sins.

Flagellants in the Dutch town of Doornik in 1349 whipping themselves with ropes in the hope that it would persuade God to free the world from the Black Death.Image source, ALAMY
Image caption,
Flagellants in the Dutch town of Doornik in 1349 whipping themselves with ropes in the hope that it would persuade God to free the world from the Black Death.

Bad air

A protective mask used by doctors during the 17th century when they called on patients suffering from the plague.Image source, ALAMY
Image caption,
A protective mask used by doctors during the 17th century when they called on patients suffering from the plague.

The quality of air was also blamed for the spread of plague - bad, stinking air known as miasma was thought to be a cause of the plague, especially in cities such as London.

In 1349, King Edward III of England issued a command to the Mayor of London, telling him to clean up the city streets by removing all waste. This included human bodily waste as well as animal dung - London had no sewers or sanitation system at the time.

  • teams of muckrakers were set up to clear the streets of animal waste
  • butchers were punished if they disposed of animal blood and remains in the street
  • fines were introduced for any member of the public caught littering

In Scotland, people called foul clengers were paid to clear out the homes of people who had died from the plague and to dispose of the bodies.

Individuals also attempted to purify the air by carrying sweet smelling flowers or herbs whilst on their daily business, or by lighting fires in their homes to overpower the bad air.

A protective mask used by doctors during the 17th century when they called on patients suffering from the plague.Image source, ALAMY
Image caption,
A protective mask used by doctors during the 17th century when they called on patients suffering from the plague.

Why did plague doctors wear 'bird' masks?

Other plague treatments

A Medieval illustration of people suffering from swollen lymph nodes, a sign of bubonic plague.Image source, ALAMY
Image caption,
A Medieval illustration of people suffering from swollen lymph nodes, a sign of bubonic plague.

The plague had no cure and once a person had caught it, there was very little the doctors could do to treat them.

In desperation some treatments were tried:

  • Buboes were burst to release the pus.
  • Buboes were covered with bread and then the bread was buried.
  • The infected individual took cold baths and avoided hot foods such as garlic and onions in an attempt to allow the body to rebalance itself.

None of the cures or treatments worked.

A Medieval illustration of people suffering from swollen lymph nodes, a sign of bubonic plague.Image source, ALAMY
Image caption,
A Medieval illustration of people suffering from swollen lymph nodes, a sign of bubonic plague.
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Aftermath of the plague

An engraving showing the Great Plague of London, 1665-1666. A passerby offers water to a man dying from the plague.Image source, ALAMY
Image caption,
An engraving showing the Great Plague of London, 1665-1666. A passerby offers water to a man dying from the plague.

While it is hard to get exact figures, it is estimated that around 25 million people in Europe were killed by the plague by 1350. That is almost a third of all people in Europe (source: ).

By 1350 the first wave of the plague was over. However, this was not the last time it would be seen in the British Isles. There were further outbreaks in the 1550s and 1640s.

In Scotland, they mostly affected the Central Belt and larger towns and cities on the east coast.

The last serious plague outbreak in the British isles was in 1665-6. London suffered particularly badly - up to 100, 000 people are thought to have died in the city. The spread of the disease began to drop after a very cold winter which may have killed off large numbers of rats. Many people argue that the Great Fire of London also played a part, destroying many rat-infested houses.

Fortunately, most of Scotland escaped the worst of this outbreak. The border with England was closed and trade and travel were banned with countries affected by the plague such as England and Holland. (Source: )

Leith, however, was not so fortunate. As a port with lots of boats arriving and departing it was at risk of infection. The 1665 plague killed over two thousand people - around half of the town's population.

Glasgow suffered an outbreak of plague as late as 1900 during the months of August and September. As a result of a late diagnosis of the 36 people who were infected, 16 people died.

An engraving showing the Great Plague of London, 1665-1666. A passerby offers water to a man dying from the plague.Image source, ALAMY
Image caption,
An engraving showing the Great Plague of London, 1665-1666. A passerby offers water to a man dying from the plague.
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Impact of the plague

The devastation caused to the population of Europe brought about a series of social and economic changes.

Social and economic

Peasants working during the harvest, 15th century.Image source, ALAMY
Image caption,
Peasants working during the harvest, 15th century.

As many of the peasantry (the poor people) had died, those who remained were able to argue for better pay, jobs, and lower rent as there was a shortage in workers.

They were also able to improve their diets as they could now access better food due to there being less demand for food and because they could afford better quality.

Landlords found that their fortunes declined as they were unable to justify charging their tenants higher rents which reduced the amount of money they made.

The fortunes of women after the Black Death were mixed.

Some were able to gain a bit more independence as more men died from the plague than women. However this fact also meant that many women suffered as the main provider for the family had passed away and they were unable to work themselves.

Peasants working during the harvest, 15th century.Image source, ALAMY
Image caption,
Peasants working during the harvest, 15th century.

The impact on religion

A colourised engraving showing a priest conducting a funeral during the Middle Ages.Image source, ALAMY
Image caption,
A colourised engraving showing a priest conducting a funeral during the Middle Ages.

The plague posed significant problems for the Christian Church.

In the Middle Ages, the Church was at the heart of everyday life. People believed in God and the Devil and believed that the Church was there to guide and defend them.

During plague years - and for years after - the Church struggled to fulfil this role.

So many people were dying that the Church did not have enough priests to hold religious services and conduct marriages, Christenings, and burials.

The common view, as supported by the Church, was that the plague was sent by God to punish the wicked.

Since the plague did not discriminate and priests were just as likely to die as the peasants they ministered to, the Church was open to accusations that it itself was wicked.

For the first time, the Church's role was being questioned.

A colourised engraving showing a priest conducting a funeral during the Middle Ages.Image source, ALAMY
Image caption,
A colourised engraving showing a priest conducting a funeral during the Middle Ages.

Impact on medicine

Coloured woodcut of doctors treating a sick patient in the Middle Ages.Image source, ALAMY
Image caption,
Coloured woodcut of doctors treating a sick patient in the Middle Ages.

It is easy to find fault with the medical responses to the plague at the time as, today, some of the ideas they had about the infection seem ridiculous.

The doctors of the time were wrong about almost everything:

  • The plague was not caused by miasma or bad smells.
  • It was not a punishment for committing sins.
  • Prayer was not a cure.
  • Lucky charms and superstition were not effective treatments.

However, medical knowledge at the time was very limited and doctors had no knowledge of germs or bacteria.

The medieval response to plague did lead to some benefits and advancements, though:

  • There was greater emphasis on public health.
  • Streets and public places were cleared of human and animal sewage.
  • Quarantine policies were commonly adopted to separate the ill from the healthy.
Coloured woodcut of doctors treating a sick patient in the Middle Ages.Image source, ALAMY
Image caption,
Coloured woodcut of doctors treating a sick patient in the Middle Ages.
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Does the plague still exist

Plague still exists in many parts of the world.

In recent years there have been outbreaks in China, the Democratic Republic of Congo and Madagascar. However outbreaks have been small.

Even if plague were to spread, as we now understand that it is caused by a bacterium, it can be treated very successfully with antibiotics.

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