Healthcare

Visualizing the History of Pandemics

Published

3 weeks ago

March 14, 2020

Nicholas LePan

The History of Pandemics by Death Toll

The History of Pandemics

Pan·dem·ic /panˈdemik/ (of a disease) prevalent over a whole country or the world.

As humans have spread across the world, so have infectious diseases. Even in this modern era, outbreaks are nearly constant, though not every outbreak reaches pandemic level as the Novel Coronavirus (COVID-19) has.

Today’s visualization outlines some of history’s most deadly pandemics, from the Antonine Plague to the current COVID-19 event.

A Timeline of Historical Pandemics

Disease and illnesses have plagued humanity since the earliest days, our mortal flaw. However, it was not until the marked shift to agrarian communities that the scale and spread of these diseases increased dramatically.

Widespread trade created new opportunities for human and animal interactions that sped up such epidemics. Malaria, tuberculosis, leprosy, influenza, smallpox, and others first appeared during these early years.

The more civilized humans became – with larger cities, more exotic trade routes, and increased contact with different populations of people, animals, and ecosystems – the more likely pandemics would occur.

Here are some of the major pandemics that have occurred over time:

Name	Time period	Type / Pre-human host	Death toll
Antonine Plague	165-180	Believed to be either smallpox or measles	5M
Japanese smallpox epidemic	735-737	Variola major virus	1M
Plague of Justinian	541-542	Yersinia pestis bacteria / Rats, fleas	30-50M
Black Death	1347-1351	Yersinia pestis bacteria / Rats, fleas	200M
New World Smallpox Outbreak	1520 – onwards	Variola major virus	56M
Great Plague of London	1665	Yersinia pestis bacteria / Rats, fleas	100,000
Italian plague	1629-1631	Yersinia pestis bacteria / Rats, fleas	1M
Cholera Pandemics 1-6	1817-1923	V. cholerae bacteria	1M+
Third Plague	1885	Yersinia pestis bacteria / Rats, fleas	12M (China and India)
Yellow Fever	Late 1800s	Virus / Mosquitoes	100,000-150,000 (U.S.)
Russian Flu	1889-1890	Believed to be H2N2 (avian origin)	1M
Spanish Flu	1918-1919	H1N1 virus / Pigs	40-50M
Asian Flu	1957-1958	H2N2 virus	1.1M
Hong Kong Flu	1968-1970	H3N2 virus	1M
HIV/AIDS	1981-present	Virus / Chimpanzees	25-35M
Swine Flu	2009-2010	H1N1 virus / Pigs	200,000
SARS	2002-2003	Coronavirus / Bats, Civets	770
Ebola	2014-2016	Ebolavirus / Wild animals	11,000
MERS	2015-Present	Coronavirus / Bats, camels	850
COVID-19	2019-Present	Coronavirus – Unknown (possibly pangolins)	70,600 (Johns Hopkins University estimate as of 9am PT, April 6)

Note: Many of the death toll numbers listed above are best estimates based on available research. Some, such as the Plague of Justinian and Swine Flu, are subject to debate based on new evidence.

Despite the persistence of disease and pandemics throughout history, there’s one consistent trend over time – a gradual reduction in the death rate. Healthcare improvements and understanding the factors that incubate pandemics have been powerful tools in mitigating their impact.

Wrath of the Gods

In many ancient societies, people believed that spirits and gods inflicted disease and destruction upon those that deserved their wrath. This unscientific perception often led to disastrous responses that resulted in the deaths of thousands, if not millions.

In the case of Justinian’s plague, the Byzantine historian Procopius of Caesarea traced the origins of the plague (the Yersinia pestis bacteria) to China and northeast India, via land and sea trade routes to Egypt where it entered the Byzantine Empire through Mediterranean ports.

Despite his apparent knowledge of the role geography and trade played in this spread, Procopius laid blame for the outbreak on the Emperor Justinian, declaring him to be either a devil, or invoking God’s punishment for his evil ways. Some historians found that this event could have dashed Emperor Justinian’s efforts to reunite the Western and Eastern remnants of the Roman Empire, and marked the beginning of the Dark Ages.

Luckily, humanity’s understanding of the causes of disease has improved, and this is resulting in a drastic improvement in the response to modern pandemics, albeit slow and incomplete.

Importing Disease

The practice of quarantine began during the 14th century, in an effort to protect coastal cities from plague epidemics. Cautious port authorities required ships arriving in Venice from infected ports to sit at anchor for 40 days before landing — the origin of the word quarantine from the Italian “quaranta giorni”, or 40 days.

One of the first instances of relying on geography and statistical analysis was in mid-19th century London, during a cholera outbreak. In 1854, Dr. John Snow came to the conclusion that cholera was spreading via tainted water and decided to display neighborhood mortality data directly on a map. This method revealed a cluster of cases around a specific pump from which people were drawing their water from.

While the interactions created through trade and urban life play a pivotal role, it is also the virulent nature of particular diseases that indicate the trajectory of a pandemic.

Tracking Infectiousness

Scientists use a basic measure to track the infectiousness of a disease called the reproduction number — also known as R0 or “R naught.” This number tells us how many susceptible people, on average, each sick person will in turn infect.

Measles tops the list, being the most contagious with a R0 range of 12-18. This means a single person can infect, on average, 12 to 18 people in an unvaccinated population.

While measles may be the most virulent, vaccination efforts and herd immunity can curb its spread. The more people are immune to a disease, the less likely it is to proliferate, making vaccinations critical to prevent the resurgence of known and treatable diseases.

It’s hard to calculate and forecast the true impact of COVID-19, as the outbreak is still ongoing and researchers are still learning about this new form of coronavirus.

Urbanization and the Spread of Disease

We arrive at where we began, with rising global connections and interactions as a driving force behind pandemics. From small hunting and gathering tribes to the metropolis, humanity’s reliance on one another has also sparked opportunities for disease to spread.

Urbanization in the developing world is bringing more and more rural residents into denser neighborhoods, while population increases are putting greater pressure on the environment. At the same time, passenger air traffic nearly doubled in the past decade. These macro trends are having a profound impact on the spread of infectious disease.

As organizations and governments around the world ask for citizens to practice social distancing to help reduce the rate of infection, the digital world is allowing people to maintain connections and commerce like never before.

Editor’s Note: The COVID-19 pandemic is in its early stages and it is obviously impossible to predict its future impact. This post and infographic are meant to provide historical context, and we will continue to update it as time goes on to maintain its accuracy.

Update (March 15, 2020): We’ve adjusted the death toll for COVID-19, and will continue to update on a regular basis.

Related Topics:coronavirus covid-19 featured history outbreaks pandemics plagues social distancing viral worst infectious diseases

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COVID-19

Every Vaccine and Treatment in Development for COVID-19, So Far

As the number of confirmed COVID-19 cases continues to skyrocket, healthcare researchers around the world are working to defeat the virus.

Published

5 days ago

April 1, 2020

Nick Routley

Every Vaccine and Treatment in Development for COVID-19

As the number of confirmed COVID-19 cases continues to skyrocket, healthcare researchers around the world are working tirelessly to discover new life-saving medical innovations.

The projects these companies are working on can be organized into three distinct groups:

Diagnostics: Quickly and effectively detecting the disease in the first place
Treatments: Alleviating symptoms so people who have disease experience milder symptoms, and lowering the overall mortality rate
Vaccines: Preventing transmission by making the population immune to COVID-19

Today’s graphics provide an in-depth look at who’s in the innovation race to defeat the virus, and they come to us courtesy of Artis Ventures, a venture capital firm focused on life sciences and tech investments.

Editor’s note: R&D is moving fast on COVID-19, and the situation is quite fluid. While today’s post is believed to be an accurate snapshot of all innovations and developments listed by WHO and FDA as of March 30, 2020, it is possible that more data will become available.

Knowledge is Power

Testing rates during this pandemic have been a point of contention. Without widespread testing, it has been tough to accurately track the spread of the virus, as well as pin down important metrics such as infectiousness and mortality rates. Inexpensive test kits that offer quick results will be key to curbing the outbreak.

Here are the companies and institutions developing new tests for COVID-19:

covid-19 diagnostics in development

The ultimate aim of companies like Abbott and BioFire Defense is to create a test that can produce accurate results in as little as a few minutes.

In the Trenches With Coronavirus

While the majority of people infected with COVID-19 only experience minor symptoms, the disease can cause severe issues in some cases – even resulting in death. Most of the forms of treatment being pursued fall into one of two categories:

Treating respiratory symptoms – especially the inflammation that occurs in severe cases
Antiviral growth – essentially stopping viruses from multiplying inside the human body

Here are the companies and institutions developing new treatment options for COVID-19:

covid-19 treatment in development

A wide range of players are in the race to develop treatments related to COVID-19. Pharma and healthcare companies are in the mix, as well as universities and institutes.

One surprising name on the list is Fujifilm. The Japanese company’s stock recently shot up on the news that Avigan, a decades-old flu drug developed through Fujifilm’s healthcare subsidiary, might be effective at helping coronavirus patients recover. The Japanese government’s stockpile of the drug is reportedly enough to treat two million people.

Vaccine

The progress that is perhaps being watched the closest by the general public is the development of a COVID-19 vaccine.

Creating a safe vaccine for a new illness is no easy feat. Thankfully, rapid progress is being made for a variety of reasons, including China’s efforts to sequence the genetic material of Sars-CoV-2 and to share that information with research groups around the world.

Another factor contributing to the unprecedented speed of development is the fact that coronaviruses were already on the radar of health science researchers. Both SARS and MERS were caused by coronaviruses, and even though vaccines were shelved once those outbreaks were contained, learnings can still be applied to defeating COVID-19.

covid-19 vaccines in development

One of the most promising leads on a COVID-19 vaccine is mRNA-1273. This vaccine, developed by Moderna Therapeutics, is being developed with extreme urgency, skipping straight into human trials before it was even tested in animals. If all goes well with the trials currently underway in Washington State, the company hopes to have an early version of the vaccine ready by fall 2020. The earliest versions of the vaccine would be made available to at-risk groups such as healthcare workers.

Further down the pipeline are 15 types of subunit vaccines. This method of vaccination uses a fragment of a pathogen, typically a surface protein, to trigger an immune response, teaching the body’s immune system how to fight off the disease without actually introducing live pathogens.

No Clear Finish Line

Unfortunately, there is no silver bullet for solving this pandemic.

A likely scenario is that teams of researchers around the world will come up with solutions that will incrementally help stop the spread of the virus, mitigate symptoms for those infected, and help lower the overall death toll. As well, early solutions rushed to market will need to be refined over the coming months.

We can only hope that the hard lessons learned from fighting COVID-19 will help stop a future outbreak in its tracks before it becomes a pandemic. For now, those of us on the sideline can only do our best to flatten the curve.

COVID-19

The 7 Best COVID-19 Resources We’ve Discovered So Far

With so much misinformation spreading on the pandemic, we’ve compiled a quality list of data-driven and unbiased COVID-19 resources for you to use.

Published

2 weeks ago

March 24, 2020

Jeff Desjardins

With all eyes on the COVID-19 pandemic and how its impact will be felt over the coming weeks and months, people are being bombarded with all kinds of noise and speculation.

Between a deadly virus, looming economic effects, and numerous government shutdowns, it’s clear that a fertile breeding ground has been created for misinformation, rumors, conspiracy theories, hot takes, and other potentially misleading content.

7 Indispensable COVID-19 Resources

At Visual Capitalist, it’s our goal to use data-driven visuals to explain the world around us.

In the last week alone, we’ve had more than 10 million people visit our site — many of them trying to understand more about COVID-19 and its effects on the economy and society.

With that in mind, we thought we’d curate a list of quality information on the virus and its impact. These COVID-19 resources are all from fact-driven, reliable sources, with some of them even being created by our in-house team and shared to our free daily mailing list.

On the below list, we start with the more contextual resources (understanding how the virus works, pandemic history, etc.) and then progress to real-time dashboards and up-to-date data.

Click any image below to see the full resource or dashboard. Many are updated daily or in real-time.

1. How Coronaviruses Work

What is a coronavirus, and how does COVID-19 fit into the mix?

This educational scrolling infographic by SCMP walks you through some of the more familiar types of coronaviruses, how they spread, and how they affect the human body.

It also relates COVID-19 to other coronaviruses that cause diseases such as Mers, Sars, and even the common cold.

2. The History of Pandemics

On March 11th, the World Health Organization declared COVID-19 a pandemic.

In this infographic, we look at the data to show you the history of pandemics — all the way from the Black Death to how the current COVID-19 situation. It helps give the historical context on how bad a pandemic can be. It’s also updated every day so you can see how COVID-19 compares to the impact of these previous events.

3. Coronavirus Simulator: Limiting the Exponential Spread

Why does the virus spread at an exponential rate, and what techniques can be used to mitigate that spread?

This fantastic interactive page by the Washington Post actively simulates what happens when the virus spreads normally, contrasting it to how it may spread in a forced quarantine environment or when social distancing is practiced.

4. Real-time COVID-19 Map

If you haven’t seen this useful real-time dashboard by Johns Hopkins University yet, it’s worth bookmarking right now.

We check the resource every day, and it has the latest numbers for COVID-19 cases, deaths, recoveries, and more — and it’s all sorted by country and/or state and province. Importantly, it also updates in real-time, so you always know you are getting the latest numbers.

5. Which Countries are “Flattening the Curve”?

Our post on which countries are “flattening the curve” has had over a million views in the last week alone, and it features the above interactive graph from Our World in Data.

Go to the post itself to see a bigger version of the logarithmic chart, which plots the progress of different countries in flattening the curves of COVID-19 infections. The interactive chart updates daily based on the latest numbers, and you can actually search for any country by using the “Search” button. Using the filters on the right side, you can also sort by region as well.

6. Tracking the Coronavirus: The Latest Figures

Even though the Financial Times is a subscription-based website, it recently published this useful COVID-19 dashboard and made it accessible to everyone.

It features various charts and tables on the countries affected, as well as ongoing assessments on the economic damage caused by the virus. Like many of the other COVID-19 resources featured on this list, it is updated on a daily basis.

7. COVID-19 Stats and Research

The above graphic is one of many available on Our World in Data, a fantastic initiative led by economist Max Roser.

Their coronavirus research page has tons of stats, citations, and data for those that want to dive deeper into the situation. It’s also updated very regularly.

Bonus: The Coronavirus Explained, and What You Should Do

While this is less data-driven than the other pieces of content, this animated video by Kurzgesagt still provides a handy explainer on how the virus works.

It’s about eight minutes long, and might help you fill other knowledge gaps.

Please Share These Resources

At a time when misinformation can be dangerous and even deadly, it is worth spreading the above COVID-19 resources to your friends, family, and colleagues.

Many of the above resources are updated daily or they contain evergreen information, meaning they are not going to go out of date any time soon.

Wishing you a safe next few months,
– The Visual Capitalist team

PS: If you have any other great resources to share, please post them in the comments!