How Smallpox Was Wiped Off the Planet By a Vaccine and Global Cooperation

The world's last recorded case of endemic smallpox was in Ali Maow Maalin, of Merka, Somalia, in October 1977. He made a full recovery.

(© WHO / John F. Wickett)

For 3000 years, civilizations all over the world were brutalized by smallpox, an infectious and deadly virus characterized by fever and a rash of painful, oozing sores.

Doctors had to contend with wars, floods, and language barriers to make their campaign a success.

Smallpox was merciless, killing one third of people it infected and leaving many survivors permanently pockmarked and blind. Although smallpox was more common during the 18th and 19th centuries, it was still a leading cause of death even up until the early 1950s, killing an estimated 50 million people annually.

A Primitive Cure

Sometime during the 10th century, Chinese physicians figured out that exposing people to a tiny bit of smallpox would sometimes result in a milder infection and immunity to the disease afterward (if the person survived). Desperate for a cure, people would huff powders made of smallpox scabs or insert smallpox pus into their skin, all in the hopes of getting immunity without having to get too sick. However, this method – called inoculation – didn't always work. People could still catch the full-blown disease, spread it to others, or even catch another infectious disease like syphilis in the process.

A Breakthrough Treatment

For centuries, inoculation – however imperfect – was the only protection the world had against smallpox. But in the late 18th century, an English physician named Edward Jenner created a more effective method. Jenner discovered that inoculating a person with cowpox – a much milder relative of the smallpox virus – would make that person immune to smallpox as well, but this time without the possibility of actually catching or transmitting smallpox. His breakthrough became the world's first vaccine against a contagious disease. Other researchers, like Louis Pasteur, would use these same principles to make vaccines for global killers like anthrax and rabies. Vaccination was considered a miracle, conferring all of the rewards of having gotten sick (immunity) without the risk of death or blindness.

Scaling the Cure

As vaccination became more widespread, the number of global smallpox deaths began to drop, particularly in Europe and the United States. But even as late as 1967, smallpox was still killing anywhere from 10 to 15 million people in poorer parts of the globe. The World Health Assembly (a decision-making body of the World Health Organization) decided that year to launch the first coordinated effort to eradicate smallpox from the planet completely, aiming for 80 percent vaccine coverage in every country in which the disease was endemic – a total of 33 countries.

But officials knew that eradicating smallpox would be easier said than done. Doctors had to contend with wars, floods, and language barriers to make their campaign a success. The vaccination initiative in Bangladesh proved the most challenging, due to its population density and the prevalence of the disease, writes journalist Laurie Garrett in her book, The Coming Plague.

In one instance, French physician Daniel Tarantola on assignment in Bangladesh confronted a murderous gang that was thought to be spreading smallpox throughout the countryside during their crime sprees. Without police protection, Tarantola confronted the gang and "faced down guns" in order to immunize them, protecting the villagers from repeated outbreaks.

Because not enough vaccines existed to vaccinate everyone in a given country, doctors utilized a strategy called "ring vaccination," which meant locating individual outbreaks and vaccinating all known and possible contacts to stop an outbreak at its source. Fewer than 50 percent of the population in Nigeria received a vaccine, for example, but thanks to ring vaccination, it was eradicated in that country nonetheless. Doctors worked tirelessly for the next eleven years to immunize as many people as possible.

The World Health Organization declared smallpox officially eradicated on May 8, 1980.

A Resounding Success

In November 1975, officials discovered a case of variola major — the more virulent strain of the smallpox virus — in a three-year-old Bangladeshi girl named Rahima Banu. Banu was forcibly quarantined in her family's home with armed guards until the risk of transmission had passed, while officials went door-to-door vaccinating everyone within a five-mile radius. Two years later, the last case of variola major in human history was reported in Somalia. When no new community-acquired cases appeared after that, the World Health Organization declared smallpox officially eradicated on May 8, 1980.

Because of smallpox, we now know it's possible to completely eliminate a disease. But is it likely to happen again with other diseases, like COVID-19? Some scientists aren't so sure. As dangerous as smallpox was, it had a few characteristics that made eradication possibly easier than for other diseases. Smallpox, for instance, has no animal reservoir, meaning that it could not circulate in animals and resurge in a human population at a later date. Additionally, a person who had smallpox once was guaranteed immunity from the disease thereafter — which is not the case for COVID-19.

In The Coming Plague, Japanese physician Isao Arita, who led the WHO's Smallpox Eradication Unit, admitted to routinely defying orders from the WHO, mobilizing to parts of the world without official approval and sometimes even vaccinating people against their will. "If we hadn't broken every single WHO rule many times over, we would have never defeated smallpox," Arita said. "Never."

Still, thanks to the life-saving technology of vaccines – and the tireless efforts of doctors and scientists across the globe – a once-lethal disease is now a thing of the past.

Sarah Watts

Sarah Watts is a health and science writer based in Chicago. Follow her on Twitter at @swattswrites.

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Amber Freed and Maxwell near their home in Denver, Colorado.

Courtesy Amber Freed

Amber Freed felt she was the happiest mother on earth when she gave birth to twins in March 2017. But that euphoric feeling began to fade over the next few months, as she realized her son wasn't making the same developmental milestones as his sister. "I had a perfect benchmark because they were twins, and I saw that Maxwell was floppy—he didn't have muscle tone and couldn't hold his neck up," she recalls. At first doctors placated her with statements that boys sometimes develop slower than girls, but the difference was just too drastic. At 10 month old, Maxwell had never reached to grab a toy. In fact, he had never even used his hands.

Thinking that perhaps Maxwell couldn't see well, Freed took him to an ophthalmologist who was the first to confirm her worst fears. He didn't find Maxwell to have vision problems, but he thought there was something wrong with the boy's brain. He had seen similar cases before and they always turned out to be rare disorders, and always fatal. "Start preparing yourself for your child not to live," he had said.

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Lina Zeldovich
Lina Zeldovich has written about science, medicine and technology for Scientific American, Reader’s Digest, Mosaic Science and other publications. She’s an alumna of Columbia University School of Journalism and the author of the upcoming book, The Other Dark Matter: The Science and Business of Turning Waste into Wealth, from Chicago University Press. You can find her on http://linazeldovich.com/ and @linazeldovich.

On May 13th, scientific and medical experts will discuss and answer questions about the vaccine for those under 16.

Photo by Kelly Sikkema on Unsplash

This virtual event will convene leading scientific and medical experts to discuss the most pressing questions around the COVID-19 vaccines for children and teens. A public Q&A will follow the expert discussion.

DATE:

Thursday, May 13th, 2021

12:30 p.m. - 1:45 p.m. EDT

LOCATION:

Virtual on Zoom

REGISTER NOW

You can submit a question for the speakers upon registering.

Dr. H. Dele Davies, M.D., MHCM

Senior Vice Chancellor for Academic Affairs and Dean for Graduate Studies at the University of Nebraska Medical (UNMC). He is an internationally recognized expert in pediatric infectious diseases and a leader in community health.

Dr. Emily Oster, Ph.D.

Professor of Economics at Brown University. She is a best-selling author and parenting guru who has pioneered a method of assessing school safety.

Dr. Tina Q. Tan, M.D.

Professor of Pediatrics at the Feinberg School of Medicine, Northwestern University. She has been involved in several vaccine survey studies that examine the awareness, acceptance, barriers and utilization of recommended preventative vaccines.

Dr. Inci Yildirim, M.D., Ph.D., M.Sc.

Associate Professor of Pediatrics (Infectious Disease); Medical Director, Transplant Infectious Diseases at Yale School of Medicine; Associate Professor of Global Health, Yale Institute for Global Health. She is an investigator for the multi-institutional COVID-19 Prevention Network's (CoVPN) Moderna mRNA-1273 clinical trial for children 6 months to 12 years of age.

About the Event Series

This event is the second of a four-part series co-hosted by Leaps.org, the Aspen Institute Science & Society Program, and the Sabin–Aspen Vaccine Science & Policy Group, with generous support from the Gordon and Betty Moore Foundation and the Howard Hughes Medical Institute.

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Kira Peikoff
Kira Peikoff is a journalist whose work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and son.