Five pandemics that changed the world

From Virus to Pandemic

Learn how new infections emerge, spread through human contact and change the world.

Find out about the organizations working every day to prevent the next great pandemic.



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From Virus to Pandemic

Learn how new infections emerge, spread through human contact and change the world.

Find out about the organizations working every day to prevent the next great pandemic.


Photo: Getty Images

The New A-Team

This unique band of researchers is going on the offensive to stop new viruses at their source.

What if we could have stopped HIV before it spread beyond its rural birthplace in Equatorial Africa? What if someone had been out there looking for new diseases in the decades before the deadly plague's explosion in the 1980s? How many millions of lives would have been saved?

Those are some of the provocative questions behind the work of Stanford professor Nathan Wolfe and his team at Global Viral Forecasting, the independent research institute he founded to pioneer new methods of early disease detection and prevention.

At GVF's headquarters overlooking San Francisco's bustling Market Street, Wolfe has assembled a unconventional and unorthodox crew of cultural anthropologists, epidemiologists, researchers, and tech wizards who have thrown out the old playbook that forces public health officials to wait and see where the next threat is going to arise before they can act.

By harvesting the various types of data available in our 21st Century world, while also engaging in old fashioned human-to-human conversations deep in the heart of the rural developing world, Wolfe and the GVF team are helping to set up a network of outposts stretching from Cameroon to Laos that will help detect potential killers at their source.

In these videos, Wolfe talks about GVF's mission, and why the waiting game is a losing game for humanity. Chief Innovation Officer Lucky Gunasekara (Wolfe calls him their "hacker,") explains how technology and data are adding new weapons to the virus hunters' arsenal. And Director of Behavior Sciences Karen Saylors shows how basic human needs are driving a lot of the activities that put the most vulnerable people in the path of new viruses.

Photo courtesy
Anne Rimoin

Finding a Hidden Scourge

How wiping out one disease may have helped another flourish.

The world celebrated in 1980 when health officials declared that smallpox had been eradicated from the planet. But UCLA infectious disease epidemiologist Dr. Anne Rimoin recently found that ridding the world of one curse may have invited another one to take root.

Rimoin, who specializes in disease surveillance in remote parts of the Democratic Republic of Congo, discovered an alarming 20-fold rise in human monkeypox cases since the 1980s. The same vaccine conquered smallpox also protected against monkeypox. The end of the vaccination campaign meant an explosion in the number of cases.

Now she and others are trying to find ways to stop the spread of another incurable disease, before the virus that causes it mutates into something even easier to transmit from human to human.

Photo: Getty Images

Outside the Box

Larry Brilliant is challenging the world's brightest thinkers to create a global warning system for our next pandemic.

From his Bay Area office, Larry Brilliant helps some of the world's most innovative organizations find new ways to solve some of the biggest threats facing the planet: climate change, access to clean water, pandemics.

The President of the Skoll Global Threats Fund started in the trenches of one the greatest battles in the history of modern medicine: the fight to wipe smallpox off the map.

Then in his late 20s, Brilliant had been studying at a monastery in India. His guru convinced him that he needed to help the World Health Organization's eradication campaign.

His days were consumed in visiting villages where hundreds of children had been struck down by the ancient plague, for which no treatment has ever been found.

"On many occasions, a mother would come up to me and say 'doctor, please treat my child,' " Brilliant says. "And that child was already dead from smallpox."

Because smallpox spreads with remarkable ease between humans, Brilliant and his teammates couldn't settle for anything less than total eradication.

After years of exhaustive work, Brilliant came face-to-face in 1975 with the last human being ever infected with naturally occurring Variola major, the virus that causes the most devastating form of smallpox. She was a little girl named Rahima Banu, who lived in Bangladesh.

"When she coughed, and the last smallpox virus landed on the hot earth and was scorched to death by the Bengal sun, it ended a chain of transmission that went back to Pharaoh Ramses V," he says.

After leaving India, Brilliant went on to earn a reputation as a guy who aimed high - and delivered.

He served as the CEO of two public companies. He founded one of the Internet's first online communities-The Well. More than one magazine called him a tech "visionary." His Seva Foundation helps prevent and cure blindness in the developing world. And he served as the inaugural Executive Director of , the Internet behemoth's philanthropic arm.

Oh, and there was the small matter of his 2006 TED Prize.

But it was his work in India that left a lasting impression.

Hundreds of millions fell victim to smallpox before it was finally erased from the earth. Brilliant's time with the WHO got him thinking about how humanity could beat other diseases before they exacted a similar nightmarish toll.

His dream: build a worldwide early-response and detection system to protect the world from disease.

"Early detection, early response," Brilliant says. "You have to attack these epidemics where they first occur. It doesn't do you any good to wait until they come to New York."

To that end, Brilliant and the Skoll Global Threats Fund support a first-of-its-kind project called CHORDS - Connecting Health Organizations for Regional Disease Surveillance - that helps countries figure out how to work together to share best practices when it comes to fighting and preventing outbreaks.

"Viruses don't know about political borders," he says.

Photo courtesy

Always On Call

An elite corps of disease detectives wages a quiet battle against threats of contagion.

They're among the first people to get a phone call when mysterious outbreaks of fever, nausea or other nasty ailments leave doctors puzzled.

But for most Americans, this elite corps of about 140 medical sleuths flies completely under the radar.

Meet the "disease detectives," or the officers of the Epidemic Intelligence Service, as they're officially known.

Since this unit of the Centers for Disease Control and Prevention program was founded by Alexander Langmuir in 1951, more than 3,200 EIS officers have waged a near-constant battle across America and around the world with some of the nastiest diseases known to man.

"These are the people on the front lines of outbreaks that affect Americans around the world," said Dr. Scott Dowell, the director of Global Disease Detection and Emergency Response at the CDC. "There's an EIS officer investigating an outbreak every week of the year."

Although they might not be well known to the public at large, Americans are probably healthier today because of the work that an EIS officer did to untangle-and halt-an outbreak before it spread.

EIS officers, who are mostly young doctors in the early stages of their careers, sign up for two-year tours of duty, either at the CDC or with a state or local public health department.

Always ready with a bag packed, they're poised fly out to the latest trouble spot at a moment's notice.

For Dowell, that meant a Thanksgiving interrupted by a multistate outbreak of viral gastroenteritis-or "stomach flu"-that was tied to oysters.

Another time there was the call to drop everything and head to Kinshasa, the capital of the Democratic Republic of the Congo, right in the middle of an Ebola outbreak.

"I had to do a lot of convincing of my wife that I would be very, very careful," Dowell told TakePart. "I think I told her I would wear one of those white suits when I got off the plane, and that didn't exactly happen."

EIS officers work under extraordinary pressure to quickly and accurately identify the source of an outbreak and help public health officials get the situation under control.

Dowell said that the CDC's aim is to get an EIS officer's boots on the ground within 24 hours of being invited to the scene.

Because people's lives are often on the line, and doctors are trying to halt whatever is sickening people from spreading even further, EIS officers' days are marked by long hours, and little down time.

"Often the cases continue to pile up and people want to know what you are going to do about it," Dowell said. "You do feel the pressure of time, and there's not a lot of sleeping."

Part gumshoe detective, part investigative reporter, EIS officers meet with public health officials, doctors and patients to quickly track down the source of an outbreak and make recommendations to help contain it.

In the field, EIS officers may collect specimens from a mystery outbreak and send them back to state-of-the-art labs at CDC headquarters in Atlanta for testing. They may also work with local health officials to develop quarantine and isolation procedures to help prevent whatever is making people sick from spreading and infecting more people.

Throughout its history, EIS has been at the forefront of nearly every major public health crisis. EIS officers have helped investigate everything from childhood lead poisoning in the 1950s to early cases of AIDS in the 1980s to the anthrax attacks after 9/11.

After completing their tours with the EIS, many officers continue working in public health, and several have gone on to serve at some of the highest levels of government: two Surgeon Generals and four of the last seven CDC directors were drawn from the ranks of EIS alums.

"I gave a little talk to our new EIS officers last week and I told them that they should have two goals for their EIS experience," Dowell said. "One was that they should have the experience of a lifetime. And two was that they should make at least one lasting contribution to public health. Their eyes went wide, but I really think that in two year at EIS they can accomplish both of those things."

Photo courtesy
Columbia University

The Scientist on Speed Dial

Mystery viruses are no match for the man who's proven he can unlock even the most complicated pathogenic puzzle.

Most scientists would probably consider it quite the accomplishment to have discovered one new virus over the course of their careers.

Dr. W. Ian Lipkin has found at least 400. In the past decade.

It's little wonder that this Columbia University professor has become the world's go-to guy when doctors and public health officials want to see if a hidden virus could be the cause of mysterious disease outbreaks in animals and humans.

From his home base at Columbia University's Center for Infection and Immunity at the Mailman School of Public Health, Lipkin directs a team of 65 scientists who work around the clock analyzing some of the most dangerous pathogens on the planet.

At times, they're working with something we've seen before, like a flu virus or a strain of Ebola. But other times, the cases in Lipkin's lab involve a puzzling, new and unknown enemy.

"There's nothing that compares with discovery," says Lipkin. "Not just my own discovery, but also the kids who work with you that are just getting started that find something themselves for the first time. Then they get the bug, and they realize that you'll have an impact far beyond anything you can achieve during the course of your own work, or even your own lifetime."

Lipkin got the bug for virus hunting early in his medical career. He was doing his second residency in neurology at the University of California at San Francisco.

The nameless scourge that would be called HIV/AIDS was just emerging. Lipkin and his colleagues chased down all kinds of leads to determine why their patients were so monstrously ill.

"It took such a long time to figure out why people were getting sick," Lipkin says. "I decided I was going to devote myself to finding ways to understand how viruses cause disease, and identify them more rapidly."

Lipkin earned his stripes as a virus hunter in the mid-1980s after reading an article in Science reporting that some unknown pathogen could cause bipolar disease, an affliction that was first identified in the 18th century.

Working on his own time, and with his own funds, Lipkin pioneered the use of a practice known as subtractive cloning to track down the culprit. In 1990 he told the world he had found the source: It was called Borna virus. Lipkin was the first person to ever identify an infectious agent using purely molecular tools.

It began a series of firsts for Lipkin.

In 1999, doctors in the New York area were puzzling over several cases of encephalitis. Lipkin, then working at the University of California at Irvine, made a startling discovery: The patients had been sickened by West Nile virus, the first time it had ever been identified in the Western Hemisphere.

Four years later, at the height of the SARS outbreak, as Chinese authorities scrambled to control the epidemic, Lipkin was hastily invited to Beijing to advise the government on containing and controlling the outbreak. His lab had developed a test for SARS, and tens of thousands of the kits were used to identify new cases.

More recently, Lipkin's lab has helped debunk the belief that a link exists between the measles vaccine and autism, identified a virus wasting salmon farms, and found that a mystery virus sickening dogs was, surprisingly, a relative of hepatitis C.

More ominously, in 2009 his team found a new Ebola-like agent called Lujo that has a nightmarishly high 80 percent death rate.

For Lipkin, the scariest part of his work isn't that some mystery plague might infect him as he goes about his research. Rather, he worries about ensuring enough young scientists will be trained to continue work that is vital to protecting the health and welfare of people around the world.

"What keeps me up these days is making sure that we can keep everything going. These are very difficult times for science," Lipkin says. "We have to intrigue young people, get them involved in it, and make sure that they take the courses and do the hard work that's required to excel in this field."


Children's Hospital Boston

Children's Hospital Boston, ranked one of the nation's best pediatric hospitals, is Harvard Medical School's primary pediatric teaching hospital and the world's largest pediatric research enterprise.

American Public Health Association

The American Public Health Association, an organization of public health professionals, aims to protect all Americans and their communities from preventable, serious health threats.

Global Viral Forecasting Initiative

GVF is an independent organization whose team has spent the last 10-plus years developing a global system to prevent pandemics.

Skoll Global Threats Fund

The mission of the Skoll Global Threats Fund is to confront global threats imperiling humanity by seeking solutions, strengthening alliances, and spurring the actions needed to safeguard the future.

The Humane Society of the United States

The Humane Society of the United States celebrates animals and confronts cruelty. The way we treat animals can impact us all. For one example, go to


HealthMap is the world's premier online disease outbreak tracking system providing free real-time global alerting of emerging public health threats to millions of users.

Mailman School's Center for Infection and Immunity

The CII is dedicated to reducing the global burden of acute and chronic diseases through microbe discovery, pathogen surveillance and translational research.

UCLA School of Public Health

The Mission of the UCLA School of Public Health is to enhance the public's health by conducting innovative research, training future leaders and health professionals from diverse backgrounds, translating research into policy and practice, and serving our local communities and the communities of the nation and the world.

Centers for Disease Control and Prevention

CDC works 24/7 saving lives, protecting people from health threats, and saving money through prevention to have a more secure nation.

Expand the timeline To learn how pandemics have changed the world
View the infographic Variola Virus

50,000 years ago

A variola virus makes the jump from rodents to ancient humans and begins to mutate.

Egypt / India

1,000 B.C.

A more modern form of the smallpox virus emerges in Egypt or India and spreads quickly, killing 30% of those infected.

First Description

910 A.D.

Famed Persian medical scholar Razi giving the first clinical description of smallpox writes, "The best thing to do during this first stage is to keep away from it, otherwise this disease might turn into an epidemic."


12th and 13th Centuries

European Crusaders probably bring smallpox back to their homeland. Periodic outbreaks kill 500,000 people every year.

Aztec Empire


Smallpox sweeps through the Aztec empire after being introduced by Spanish conquistadores. Up to 50% of the empire's capital Tenochtitlan may have died in a period of two years.

First Vaccine


English physician Edward Jenner shows that inoculation with cowpox - a similar, but less harmful, virus - could protect against smallpox infection. Jenner's discovery was the first indication that the spread of smallpox could be controlled. Various nations began vaccination programs aimed at curbing the ancient scourge.

Eradication Program


The World Health Organization launches a coordinated global eradication campaign.



The WHO declares that smallpox has been eradicated.

Virus Dormant


Variola major, the virus that causes smallpox, sits dormant in two secure laboratories, one in the United States, the other in Russia. Arguments continue as to whether to destroy all remaining samples.