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The 10 Worst Pandemics in History

Larry Slawson received his Master's Degree from UNC Charlotte in 2018. He has a keen interest in microbiology.

The 10 worst pandemics in human history.

The 10 worst pandemics in human history.

10 of the World's Deadliest Pandemics

Throughout world history, a variety of viruses and bacteria have infected the human population, reaching catastrophic levels within only a short span of time. From cholera to influenza, each of these diseases has proven disastrous in terms of both infection and mortality rates. This work examines the ten worst pandemics in history, and provides a direct analysis of their causes, impact, and fatality rates. It is the author’s hope that a better understanding of these tragedies will accompany readers following their completion of this work.

Selection Criteria

Selection for the ten worst pandemics in history is based on a number of criteria. First and foremost, the number of fatalities inflicted by each disease is a primary indicator of the pandemic’s overall impact on society. In conjunction with the number of deaths, infection and mortality rates are also taken into consideration for this work since both are indicative of the overall potency of each specific disease.

Finally, and perhaps most importantly, the social, economic, and political impact of each pandemic is also considered as all of these factors are known to hamper recovery efforts in a substantial way. While imperfect, the author believes that these criteria offer the best means for determining the ten worst (and deadliest) pandemics in history.

The 10 Worst Pandemics in History

  • Cholera Pandemic of 1899
  • Flu Pandemic of 1968
  • Flu Pandemic of 1889
  • Cholera Pandemic of 1852
  • Asian Flu
  • Antonine Plague
  • Plague of Justinian
  • Spanish Flu of 1918
  • HIV/AIDS
  • The Black Plague

What Is the Difference Between Outbreaks, Epidemics, and Pandemics?

The biggest difference between “outbreaks,” “epidemics,” and “pandemics” is the scope and magnitude of each. The following outlines each stage of a disease’s progression:

What Is an Outbreak?

An outbreak refers to a small but unusual increase in the number of disease cases for a specific locality. Examples include sudden spikes in a virus (such as the Flu) that exceed normal expectations. When caught early, outbreaks are relatively easy to contain as their source can be identified; thus, allowing health officials to quarantine those affected before the disease can spread further (tamu.edu).

What Is an Epidemic?

Epidemics are declared when a disease spreads to a wider area, infecting a large number of individuals within a relatively large geographic area (tamu.edu). An epidemic is usually the next stage in a disease’s progression, and is declared when containment efforts of a smaller “outbreak” are insufficient. Containment at this stage is not impossible, but remains incredibly difficult as the geographical scope of the disease’s spread is far larger, making quarantines extremely difficult to manage for health authorities.

What Is a Pandemic?

Pandemics are the final stage of a disease’s progression, and refers to an international disease that is out of control. Pandemics occur when an epidemic spreads to several countries or regions causing a sufficient number of infections. COVID-19 (commonly known as the Coronavirus) is an excellent example of a pandemic, as the disease started out small (an outbreak in Wuhan), before progressing to epidemic and pandemic levels within months. While pandemics can eventually be controlled with time, they require substantial effort to halt.

Up-close image of Vibrio cholerae, the bacteria responsible for Cholera.

Up-close image of Vibrio cholerae, the bacteria responsible for Cholera.

10. Cholera Pandemic of 1899

  • Estimated Death Toll: 800,000
  • Origins: India
  • Date(s): 1899 to 1923

The Cholera Pandemic of 1899 (sometimes referred to as the “Sixth Cholera Pandemic”) was a major outbreak of cholera that originated in India in the late 19th century. Rapidly spreading throughout the world within a matter of years, the pandemic soon reached the Middle East, Africa, Eastern Europe, Russia, as well as Western Europe and the United States by 1910.

How Many People Died During the 1899 Cholera Pandemic?

Although cases in the Western world were quickly isolated and eliminated, deaths from the disease reached unprecedented heights in India, the Middle East, and Russia due to the absence of medical facilities and treatment options. By 1923, the Sixth Cholera Pandemic was credited with over 800,000 deaths worldwide, making it one of the deadliest pandemics in human history. Today, it is largely accepted by the scholarly community that poor sanitation was the major cause of the 1899 pandemic.

What Is Cholera?

Cholera is an infectious disease that is believed to originate in contaminated water supplies. It is most common in areas that lack sanitation facilities and suffer from overcrowding. As a result, war-torn areas are often a major source of the disease, as well as third-world countries that lack government funds to provide modern water and sewage treatment systems (webmd.com).

What Are the Signs and Symptoms of Cholera?

Symptoms of a cholera infection can begin within a few hours of infection (or as long as five days after exposure). Symptoms are generally mild and involve diarrhea, vomiting, and lower blood pressure. However, it is estimated that 1 in 20 people will develop serious symptoms after exposure, involving severe diarrhea and vomiting that will lead to dehydration if not treated. This, in turn, can lead to shock, low blood sugar (hypoglycemia), lower potassium levels, and even kidney failure (mayoclinic.org).

"Hong Kong" Flu of 1968.

"Hong Kong" Flu of 1968.

9. Flu Pandemic of 1968

  • Estimated Death Toll: 1 Million
  • Origins: British Hong Kong
  • Date(s): 1968

The Flu Pandemic of 1968 was first recognized on 13 July 1968 in British Hong Kong. Classified as a “Category 2” pandemic (with a fatality rate of 0.1 to 0.5 percent), the disease was believed to have been caused by an H3N2 strain of the Influenza A virus. Within weeks of the outbreak, numerous cases began springing up in Vietnam, Singapore, India, and the Philippines. With little resources to control its spread, the virus quickly entered Australia, Europe, and the United States by the end of the year.

How Many People Died During the 1968 Flu Pandemic?

Despite its relatively low fatality rate, millions became infected from the virus leading to higher death rates (particularly in China where higher population density led to greater infection rates). In Hong Kong, alone, it is estimated that nearly 500,000 people were infected by the disease. For these reasons, the 1968 Flu Pandemic was extremely problematic, killing an estimated 1 million people in a matter of months. Of these million, nearly 100,000 people died in the United States.

What Is Influenza?

Also known as the “Flu,” influenza is an infectious virus believed to have been around for thousands of years. Believed to originate from a variety of animals, there are currently four major strains of the virus, including types A, B, C, and D (however, different and more potent strains occasionally arise from time to time). Yearly outbreaks of this disease are common, worldwide, with an estimated three to five million cases every year.

What Are the Signs and Symptoms of Influenza?

Symptoms of an influenza infection usually begin suddenly (within 1 to 2 days following exposure). Common symptoms include body chills and aches, as well as fever. Depending on the strain of influenza, other common symptoms include coughing, runny nose, congestion, sore throat, fatigue, headache, watery eyes, and hoarseness. In severe cases, viral pneumonia and secondary bacterial pneumonia can develop, causing life-threatening conditions. While the majority of individuals make full recoveries from the Flu, infants, elderly people, and those with compromised immune systems are at a higher risk of developing life-threatening complications.

The H3N8 virus responsible for the Russian Flu pandemic.

The H3N8 virus responsible for the Russian Flu pandemic.

8. Russian Flu

  • Estimated Death Toll: 1 Million
  • Origins: Saint Petersburg, Russia
  • Date(s): 1889 to 1890

The Flu Pandemic of 1889 (also known as the “Russian Flu”) was a deadly pandemic caused by a subtype of the Influenza A strain known as H3N8. First reported in Saint Petersburg, Russia on 1 December 1899, the virus was able to quickly spread throughout the Northern Hemisphere due to improper quarantine protocols. Due to the large number of railroad networks and an increase in transatlantic travel (via boat) at this time, the virus even managed to spread all the way to the United States by 12 January 1890. In less than four months, the outbreak reached pandemic levels, as all major countries of the world began to report a substantial number of cases.

How Many People Died During the Russian Flu Pandemic?

Despite having a relatively low mortality rate, the number of infected individuals reached into the millions by mid-1890, worldwide. As a result, it is currently estimated that approximately 1 million people died as a result of the 1889 “Russian Flu” Pandemic (wired.com). In an era when the study of bacteriology (and virology) was first beginning to take shape in scientific circles, little was understood about containment protocols for diseases. As a result, the Russian Flu was afforded an opportunity to spread like wildfire to surrounding countries as modern containment protocols were not followed.

The rapid pace of industrialization and technological advancement in the Nineteenth Century may also be to blame for the spread of the Russian Flu. Increased travel (via boat and railways), along with notable increases in the population of cities all played a major role in the spread of influenza from person-to-person (ncbi.gov).

Microscopic image of Vibrio cholerae (responsible for Cholera).

Microscopic image of Vibrio cholerae (responsible for Cholera).

7. Cholera Pandemic of 1852

  • Estimated Death Toll: 1 to 2 Million
  • Origins: India
  • Date(s): 1852 to 1860

The Cholera Pandemic of 1852 (also referred to as the “Third Cholera Pandemic”) was a major outbreak that originated in India during the mid-1800s. Considered one of the worst pandemics of the Nineteenth Century, the disease quickly spread beyond India’s borders to infect large swathes of Asia, Africa, Europe, and eventually North America. By 1854, the disease reached unprecedented heights, worldwide, becoming the worst year for the pandemic’s deadly cycle. Despite being a gruesome year, however, 1854 also became a turning point in the fight against cholera as British physician John Snow – who was working in London at the time – was able to identify contaminated water as the source for cholera transmission. His unprecedented discovery not only helped save thousands in Great Britain, but also facilitated a number of measures to combat the disease, globally.

How Many People Died During the Cholera Pandemic of 1852?

Due to a lack of records from this time period, the exact death toll of the Third Cholera Pandemic is difficult to determine with certainty. However, it is largely agreed upon by scholars that fatalities were somewhere between 1 and 2 million deaths between 1852 and 1860. One of the worst areas affected by the disease was Imperial Russia, where deaths may have been higher than 1 million. Likewise, in 1854 (the height of the cholera pandemic), deaths in Great Britain alone were nearly 23,000 with thousands of others falling victim to the disease around the globe.

Microscopic image of the H2N2 virus responsible for the Asian Flu.

Microscopic image of the H2N2 virus responsible for the Asian Flu.

6. Asian Flu

  • Estimated Death Toll: 1 to 4 Million
  • Origins: Guizhou, China
  • Date(s): 1957 to 1958

The Asian Flu of 1957 (also referred to as the “Asian Flu Pandemic of 1957), was a major outbreak that originated in China during the early months of 1957. Later classified as a “Category 2” pandemic, the outbreak was the second influenza pandemic to occur during the 1900s, and was believed to have been a subtype of Influenza A known as H2N2 (a disease that later mutated into H3N2 only a few years later, causing the Hong Kong Flu Pandemic).

Shortly after discovering the new strain in 1957, doctors were unable to control the disease in its early stages. As a result, the virus quickly spread beyond China’s borders into surrounding regions. Within months, the Asian Flu reached pandemic status as much of the Northern Hemisphere, including Europe and North America fell victim to its spread. By the early months of 1958, millions of Americans, Europeans, and Asians had become ill from the deadly virus, with children, the elderly, younger adults, and pregnant women being most susceptible to infection.

How Many People Died During the Asian Flu Pandemic?

Overall estimates regarding the number of deaths caused by the Asian Flu are difficult to determine, as sources vary significantly by country/region. However, it is largely accepted by the scholarly community that nearly 1 to 4 million people died of the Asian Flu, with the World Health Organization (WHO) stating that 2 million deaths were the most likely figure, worldwide. Despite having only a 0.3-percent mortality rate, these large numbers are explained by the fact that tens of millions of individuals were infected by the virus.

What Are the Signs and Symptoms of Asian Flu?

During the 1957 pandemic, symptoms of the Asian Flu mimicked many of the common influenza symptoms, including: body chills, muscle aches, sore throat, runny nose, and coughing. High fevers were also extremely common, along with nose bleeds. In more severe cases, complications involving pneumonia, bronchitis, and cardiovascular issues were known to develop in approximately 3-percent of cases.

Microscopic image of the Variola Virus (Smallpox). This disease was likely responsible for the Antonine Plague.

Microscopic image of the Variola Virus (Smallpox). This disease was likely responsible for the Antonine Plague.

5. Antonine Plague

  • Estimated Death Toll: 5 Million
  • Origins: Unknown
  • Date(s): 165 to 180 A.D.

The Antonine Plague of 165 AD (also known as the “Plague of Galen), was an ancient pandemic that affected the Roman Empire between 165 and 180 AD. Believed to have been brought back to the Roman Empire by troops who were returning from military campaigns in East Asia at the time, the disease quickly spread throughout Europe and the Mediterranean, claiming countless lives in its wake (including the Roman Emperor, Lucius Verus).

Although little is known about the disease that affected the Roman Empire at this time, records from a Greek physician known as Galen indicate that the plague might have been either smallpox or measles. In his records, Galen suggested that fever, diarrhea, and pharyngitis (inflammation of the throat) were common amongst the disease’s victims, with skin eruptions (including pustular formations) prominent by the ninth day of infection. For these reasons, smallpox is often used by scholars to describe the Antonine Plague of 165 AD, as the symptoms appear to match.

How Many People Died During the Antonine Plague?

Due to the fact that many of the sources pertaining to the Antonine Plague are ancient, overall numbers are difficult to determine for overall deaths. However, it is widely accepted that nearly 5 million people died during the Antonine Plague, which struck the Roman Empire in a series of two separate waves. Records from the Roman historian, Dio Cassius, indicate that the disease was so severe that nearly 2,000 people were dying each day in Rome alone (loyno.edu). With an estimated mortality rate of nearly 25-percent, some regions of the Roman Empire experienced population declines of nearly 33-percent. Likewise, the Roman Army (the original carriers of the disease) were decimated by the plague, leaving Rome vulnerable for quite some time (loyno.edu).

Image of Yersinia pestis; the disease responsible for Black Plague and the major cause of the Justinian Plague.

Image of Yersinia pestis; the disease responsible for Black Plague and the major cause of the Justinian Plague.

4. Plague of Justinian

  • Estimated Death Toll: 25 Million
  • Origins: Central Asia
  • Date(s): 541 to 542 A.D.

The Plague of Justinian refers to a pandemic that affected the Eastern Roman Empire (Byzantine) around the year 541 AD. Believed to have originated in Central Asia, it is hypothesized that nomadic tribes from the region may have contributed to the disease’s spread into the Byzantine Empire and Mediterranean. Upon reaching Eastern Europe, the disease quickly spread out of control, devastating the populations of the Mediterranean and the city of Constantinople. Although the plague subsided after a year, the disease returned periodically for the next few centuries leaving massive fatalities in its wake.

What Caused the Plague of Justinian?

Using historical records as a reference point, scholars believe that the Plague of Justinian was the result of Bubonic Plague (and was likely the first recorded incident of the Plague in history). Known in the scientific community as Yersinia pestis, the bacteria is believed to be transmitted via rats and fleas.

How Many People Died During the Plague of Justinian?

Overall deaths for the Plague of Justinian are difficult to determine as early records appear to be exaggerated. Nevertheless, it is generally accepted by scholars that approximately 25 million individuals died during the pandemic’s first wave. After spreading further into the continent, it is estimated that the plague killed nearly half the population of Europe before it began to subside. In Constantinople, alone, nearly 5,000 people died each day from the bacteria, resulting in a loss of approximately 40-percent of the city’s population.

What Are the Signs and Symptoms of Bubonic Plague?

Symptoms of Bubonic Plague usually begin suddenly, and involve headache, chills, fever, and muscle weakness. Swollen and tender lymph nodes are also quite common, as transmission of the bacteria from flea bites usually enter the lymphatic system (where they begin to multiply rapidly). Although modern antibiotics are highly effective against Plague, lack of treatment often leads to death as the bacteria spreads throughout the body causing severe complications, including shock and organ failure (cdc.gov).

American soldiers being treated for the Spanish Flu of 1918.

American soldiers being treated for the Spanish Flu of 1918.

3. Spanish Flu

  • Estimated Death Toll: 25 to 50 Million
  • Origins: Unknown
  • Date(s): 1918 to 1919

The Spanish Flu of 1918 refers to a severe influenza pandemic that spread worldwide between 1918 and 1919. Believed to have been “caused by an H1N1 virus with genes of avian origin,” the disease was first identified by military personnel in the United States during the Spring of 1918, before it began to spread out of control only a few weeks later (cdc.gov).

Due to the massive mobilization efforts of the First World War that was occurring at this time, the virus was afforded a unique opportunity to spread worldwide with relative ease via soldiers, sailors, and a large array of civilian contractors. By the time the pandemic began to subside a year later, nearly a third of the world’s population had been infected by the virus with an estimated 500 million cases. To this day, the Spanish Flu is considered one of the deadliest pandemics to have arose in human history.

How Many People Died During the Spanish Flu of 1918?

In addition to infecting nearly 27-percent of the world’s population, mortality rates for the Spanish Flu are estimated to have been between 10 and 20-percent (depending on the individual’s age and location). As a result, it is estimated that nearly 25 to 50 million people died as a result of the disease. In fact, infection rates were so high that wartime censors in the United States, United Kingdom, France, and Germany tried to cover up mortality rates for the sake of morale.

It remains unclear why so many individuals died of the Spanish Flu. Even younger adults faced higher mortality rates than usual for an influenza outbreak. Scientists have hypothesized, however, that the Spanish Flu may have triggered a cytokine storm (a sudden increase in the body’s immune cells which, in turn, causes severe damage to the body) in many of the disease’s victims. Other reports have suggested that hospital overcrowding, malnourishment, as well as poor hygiene (and sanitation) may have played a role in mortality rates as well.

Pandemic Quote

"The fact that there was no catastrophic pandemic in recent history does not mean there won't be another one. And we are certainly not prepared for the next pandemic."

— Bill Gates

HIV (in green) attacking a healthy human cell.

HIV (in green) attacking a healthy human cell.

2. HIV

  • Estimated Death Toll: 32 Million
  • Origins: Central Africa
  • Date(s): 1981 to Present

The Human Immunodeficiency Virus (HIV) refers to a viral infection that suppresses the body’s immune system, and prevents it from fighting off infections (cdc.gov). First identified in 1981, the virus quickly progressed to pandemic levels as its spread has proven impossible to halt, worldwide. Today, it is estimated that approximately 37.9 million people are currently living with the disease, with over 75 million individuals being infected (globally) by HIV since it was first identified in 1981. Despite many advances in treatment, no effective cure exists for the virus. Nevertheless, antiviral medications have proven effective in recent years with controlling HIV and its symptoms, as well as prolonging the onset of AIDS (Acquired Immunodeficiency Syndrome).

HIV and AIDS continue to be one of the most serious pandemics in human history as infection rates have remained relatively stable for several decades, worldwide. This is particularly true for Sub-Saharan Africa where infection rates are greater than any other region. And while Western medicine offers promising results for infected individuals, many of these treatments remain unavailable to people living in third-world countries at this time.

How Many People Have Died During the HIV/AIDS Pandemic?

Out of approximately 75 million cases, it is estimated by the World Health Organization (WHO) that nearly 32 million people have died from HIV/AIDS since 1981 (who.int). However, these numbers are not entirely accurate, as researchers believe that the disease may have been around since the 1800s (resulting in far greater unreported deaths). With nearly 38 million people currently living with the disease, these numbers will likely increase in the years to come until an effective vaccine can be developed to counteract the disease’s progression. It is currently estimated that nearly 940,000 people die of HIV/AIDS every year, with 66-percent of these deaths occurring in Sub-Saharan Africa, alone.

What Are the Signs and Symptoms of HIV?

Diagnosis of HIV is extremely difficult in its early stages, as the disease often shows no symptoms. Although people sometimes experience flu-like symptoms during the first four weeks of exposure, these symptoms are relatively general, in nature, and include fever, rash, chills, muscle aches, fatigue, sore throat, and swollen lymph nodes. For this reason, it is vital that individuals get tested by a medical professional if they suspect HIV exposure.

Yersinia pestis viewed with fluorescent lighting (bacteria responsible for the Black Death).

Yersinia pestis viewed with fluorescent lighting (bacteria responsible for the Black Death).

1. The Black Death

  • Estimated Death Toll: 200 Million
  • Origins: Central Asia
  • Date(s): 1346 to 1353

The Black Death (also known as the “Black Plague,” “Great Plague,” or “Great Bubonic Plague”) was a devastating pandemic that ravaged Eurasia between 1346 and 1353. Believed to have originated from a bacterium known as Yersinia pestis, the disease likely originated in Central Asia and reached Europe via the Silk Road as early as 1343. Caused by rats and fleas, the Black Death quickly spread throughout Europe as overcrowding, poor hygiene, and inadequate sanitation provided the disease an avenue to infect large groups of humans with ease. In its wake, the Plague profoundly changed the course of European history, leading to a variety of social, economic, and religious upheavals in the years and decades that followed.

Contrary to popular belief, incidences of the Black Plague were evident several centuries before the Fourteenth Century. Around 542 A.D., for example, the Justinian Plague (caused by Yersinia pestis) ravaged the Byzantine Empire with deaths exceeding 25 million. As devastating as these figures were, however, it wasn’t until the 1300s that the true power (and potential) of Bubonic Plague was realized, as population density allowed for unprecedented opportunities for the disease to spread from human-to-human.

How Many People Died During the Black Death?

Due to the absence of accurate documentation from this time period, it is difficult to determine the overall number of deaths caused by the Black Death. Most scholars agree, however, that an estimated 200 million people perished across Eurasia as the Plague spread (with Europe, in particular, experiencing an extreme number of cases). If completely accurate, this figure demonstrates that approximately 50 to 60-percent of the European population was wiped out as a result of the Plague. Likewise, the Middle East and parts of North Africa are believed to have experienced a population decline of nearly 33-percent. For these reasons, the Black Death was the deadliest pandemic in human history.

Concluding Thoughts

In closing, pandemics continue to be a tremendous threat to human populations, worldwide. Although protective measures exist to combat the world’s various diseases, containment of outbreaks is not always possible; leaving many to face the prospect of infection. With the mutation of viruses and bacteria (along with their growing resistance to antiviral and antibiotic remedies) on the rise, outbreaks, epidemics, and pandemics will continue to be a major issue for humans in the years and decades that lie ahead.

What measures exist to combat viruses and bacteria in the future? What will future governments do to protect individuals against the threat of pandemics? Finally, and perhaps most importantly, what scientific (and medical) resources will be needed to quell the spread of deadly diseases in the years that lie ahead? Only time will tell.

Works Cited

Articles/Books:

Images:

  • Wikimedia Commons

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2020 Larry Slawson

Comments

Larry Slawson (author) from North Carolina on March 21, 2020:

Thank you, Lorna! I am really hopeful too! Its scary how fast the Coronavirus was able to spread. But like you said, advancements in science and medicine may help us ride this one out.

Lorna Lamon on March 21, 2020:

This is an excellent article Larry and I wasn't aware of some the very early Pandemics. It's shocking the number of deaths and now we are in the middle of another. We are certainly more advanced in the fields of science and medicine so I am hoping that we will ride this one out. Thank you for sharing this informative read.

Larry Slawson (author) from North Carolina on March 20, 2020:

Thank you so much, Pamela! I'm so glad you enjoyed :) Yes, this article took awhile to write haha. I really enjoyed the research though. There were quite a few on this list that I had never heard of before.

Pamela Oglesby from Sunny Florida on March 20, 2020:

The pandemics are horrible. I didn't know about some of the ones on your list. You explained pandecmics very wee and you have given us a weath of information in this excellent article. I am sure this article required a lot of research on your part and the results are obvious.

Have a nice weekend, Larry.

Larry Slawson (author) from North Carolina on March 20, 2020:

Thank you Miebakagh and femi! So glad you enjoyed!

Miebakagh Fiberesima from Port Harcourt, Rivers State, NIGERIA. on March 20, 2020:

Hello Larry, this is an interesting article on disease and virus. It is informing. You have done your research well. It is now up to every reader to step up their sense of hygiene. Thanks for sharing.

femi from Nigeria on March 20, 2020:

Interesting article mankind seem to face different challenges like Ebola,Lasa fever,malaria parasite etc

Larry Slawson (author) from North Carolina on March 19, 2020:

Thank you, John! I was thinking the same thing while writing this article. It will be interesting to see how Coronavirus compares with a lot of these in the months ahead. I really hope our governments can get this thing under control.

John Hansen from Queensland Australia on March 19, 2020:

What an in-depth and informative article, Larry. It helps us put the current Coronavirus in perspective, though we still don’t know just how it will rate in comparison with these others as infection and death tolls are still rising. I appreciate your research.

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