• Leprosy was one of the earliest pandemics in recorded history, sweeping through Europe in the 11th century.
  • The Spanish flu was the deadliest pandemic ever, killing as many as 50 million people worldwide.
  • The H1N1 virus of 2009 began in the United States and spread worldwide.
  • Coronavirus is not yet classified as a pandemic, as China has quarantined Wuhan and other cities in an effort to stop the disease from reaching pandemic-level.
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History has seen some truly devastating pandemics that have killed hundreds of thousands to millions of people.

According to the World Health Organisation, a pandemic is “an epidemic occurring worldwide, or over a very wide area, crossing international boundaries and usually affecting a large number of people.”

When compared with the scale of other diseases in history, the coronavirus has not yet reached pandemic levels – although our ultra-connected world could propagate a spread of disease like never before.

Here are 12 of history’s worst disease outbreaks that caused widespread fear.

Leprosy was one of the earliest pandemics, spreading through Europe in the Middle Ages.

Michael Maslan/Corbis/VCG via Getty ImagesPeople with leprosy in Jerusalem in the 1870s.

Leprosy, which reached pandemic levels in the 11th century, is one of history’s most misunderstood diseases. For centuries, people believed the disease was hereditary and even served as a punishment from God. Patients were stigmatised and exiled. When they weren’t banished from society, they had to wear special clothing and even ring bells to let others know they were coming.

The extreme fear of the disease was due to one of its symptoms, tissue necrosis, in which parts or entire limbs turn black.

Though there are still leprosy patients today, the disease is curable with multi-drug therapy.

Tauseef Mustafa/AFP via Getty ImagesA patient at a leprosy hospital in India in 2017.

There is still a sizable number of reported leprosy cases. In 2018, the World Health Organisation (WHO) reported 208,619 new cases worldwide.

However, the disease has been curable since 1981, when the WHO recommended multi-drug therapy (MDT) to treat leprosy patients. MDT lasts either six months or one year, depending on the severity of the disease, but is successful in curing those affected.

The Black Death, also known as the bubonic plague, killed one-third of Europe’s population in the 14th century.

Hulton Archive/Getty Images People praying for relief from the plague, circa 1350.

The Black Deathwas caused by the Yersinia pestis bacteria, which is found in many parts of the world, including the United States.

The plague was believed to have been spread by rats.

Time Life Pictures/Mansell/The LIFE Picture Collection via Getty ImagesA black rat, early 19th century engraving.

The Black Death is believed to have killed about 25 million people, spreading through Europe and Asia on the backs of fleas and rats.

Many royals in the 14th century died from the disease, including Peter IV of Aragon, King Alfonso XI of Castile, and Joan, daughter of the English king Edward III.

In the 17th century, the Great Plague of London killed 20% of the city’s population.

Fine Art Images/Heritage Images/Getty Images Great Plague of London, 1665.

The Great Plague of London was the second insurgence of the bubonic plague and resulted in 68,596 recorded deaths.

The London city streets, which at the time were filled with waste, attracted rats that carried the disease.

There have been seven cholera pandemics. The first began in 1817.

Ann Ronan Pictures/Print Collector/Getty Images The cholera epidemic in Naples as seen on a wood engraving from 1884.

Though recorded before 1817, that was the year the disease reached pandemic level after originating in the Ganges Delta in India. It spread through Asia to Europe and lasted for six years.

Cholera still affects people today, with the WHO recording 1.3 to 4 million cases annually. However, up to 80% of cases can be treated with an oral rehydration solution.

The Russian flu began in Siberia and Kazakhstan before spreading through Europe to kill 360,000 people by 1890.

Universal History Archive/Universal Images Group via Getty Images Influenza in the Channel Fleet, an 1890 engraving.

The Russian flu was the largest influenza pandemic of the 19th century.

The disease was able to spread quickly at the time through increased populations in cities and towns, where people were living in closer proximities. The development of the rail system also spread the flu, as people were able to travel quickly to distant places, taking their contagious symptoms with them.

Smallpox is believed to have killed 300 million people through history.

Hulton Archive/Getty ImagesA ward in the Hampstead Smallpox Hospital in London, circa 1820.

Though the exact origin of smallpox is unknown, the disease is believed to have originated in Ancient Egypt, as smallpox-like scars were found on three mummies.

The greatest spreads of smallpox are attributed to world exploration and growing trade routes. In the 16th, 17th and 18th centuries, European colonisation led to huge outbreaks in Africa, North America, and Australia, countries where there was no developed immunity to such a powerful disease.

The smallpox vaccine was the first successful vaccine in history.

Hulton Archive/Getty Images Edward Jenner inoculates a child against smallpox in 1796.

On average, three out of 10 people who got smallpox died, and those who survived were often left with severe scars.

Edward Jenner, pictured above, developed the history’s first vaccine while trying to treat smallpox. He placed tiny bits of material from infected scabs on healthy patients, whose bodies were able to develop antibodies, protecting them from future infection.

The Spanish flu was an avian-borne illness that killed more than 50 million worldwide.

Hulton Archive/Getty ImagesNurses care for victims of the Spanish flu in 1918.

The Spanish flu in 1918 was the deadliest pandemic in history, killing 50 million people worldwide, and infecting an estimated 500 million, or one third of the world population at the time.

There were no effective drugs or treatments for the disease. Instead, people were ordered to wear masks, and all schools, businesses and theatres were closed.

The disease was so severe that victims could sometimes die within hours or days of showing symptoms.

Life expectancy in the United States dropped by about 12 years in the first year of the Spanish flu pandemic.

National Archives/The LIFE Picture Collection/Getty Images Seattle policemen wearing protective masks, 1918.

The disease was so severe that in the United States, there was a ban on spitting on the street, as it was believed to help spread the disease.

The Asian flu began in Hong Kong and then spread from China to the United States and the UK in the 1950s.

Getty Images Japanese schoolgirls wearing protective masks.


The Asian flu was the second major flu pandemic of the 20th century, following the Spanish flu. The outbreak caused an estimated 1 to 2 million deaths worldwide. It was caused by a virus known as influenza A subtype H2N2.

Flu-infected people were repatriated from London, where the disease had a devastating effect.

In the first months of the Asian flu pandemic, the virus mainly spread through China and the surrounding areas.

However, the disease soon spread to the United Kingdom, and by December 1957, a total of 3,550 deaths had been reported in England and Wales.

HIV/AIDS was first recognised as a disease in 1981 and is believed to have killed 35 million people worldwide.

Dirck Halstead / The LIFE Images Collection via Getty Images / Getty Gay advocates protest the lack of AIDS research, in the vacation town of then-president George Bush, in Kennebunkport, Maine.

HIV, human immunodeficiency virus, if left untreated, develops into AIDS, acquired immunodeficiency syndrome, which is a devastating disease in which the body’s immune system collapses. If untreated, it is a fatal diagnosis.

However, treatment today is incredibly successful at fighting the disease. Many of those infected can reach undetectable levels where they are extremely unlikely to infect others.

Princess Diana was passionate about ridding the world of the HIV/AIDS stigma.

Tim Graham Photo Library via Getty Images Princess Diana visits an HIV/AIDS hostel in Brazil, 1991.

Princess Diana was one of many advocates against the stigmatization of HIV/AIDS.

Though we now know that anyone can get AIDS, as the disease is spread through unprotected sex, the sharing of needles and through birth, it was first believed to only affect gay men.

The disease was first misnamed as GRID, gay-related immune deficiency, and this resulted in undue stigma towards the gay community.

The H1N1 virus of 2009 was a new type of influenza and was first detected in the United States.

Jessica Rinaldi / ReutersThe entrance to a flu treatment facility in Arlington, Texas, in 2009.

The H1N1 flu first developed in the United States and quickly spread throughout the world. The CDC estimated there were approximately 60.8 million cases in the US, which led to 12,469 deaths.

Unlike many other flu outbreaks, the disease primarily affected children and the middle aged. This was because nearly a third of people over 60 already had antibodies in their system from previous flu outbreaks that protected them from the virus.

Ebola is an epidemic, rather than pandemic, as it has been mainly localised in Africa.

Getty Images / John Moore A health worker in protective clothing carries a child suspected of having Ebola in Liberia in 2014.

Ebola was first discovered in Africa, in what is now the Democratic Republic of the Congo. It is named for the Ebola River, near where it was first found.

Ebola was previously known as Ebola hemorrhagic fever due to the internal and external bleeding caused by the disease. When contracted, Ebola has an average mortality rate of about 50%, and the disease has killed more than 11,000 people since 1976.

An outbreak in West Africa between 2014 and 2016 spread to other countries in Africa, Europe, and the US. Two years after it was first discovered, the outbreak had caused a reported 11,325 deaths, according to the CDC.

Though mostly localised in China, coronavirus has caused widespread panic this year.

Reuters Chinese President Xi Jinping inspects the novel coronavirus prevention and control work at Anhuali Community in Beijing

Coronavirus originated in Wuhan, China, and has killed more than 2,000 people and infected more than 75,000. The virus has now spread to at least 25 other countries, and six deaths have been reported outside China, in Hong Kong, Japan, the Philippines, and France.

The disease has not yet been officially declared a pandemic, but it could reach that level if it continues to spread.

Original Author ZOE ETTINGER FEB 2020 https://www.businessinsider.com.au/disease-outbreaks-deadliest-history-2020-2