American History Tellers - Conquering Polio | Beyond the Microscope | 2

Episode Date: January 14, 2026

By the late 1940s, the National Institute of Infantile Paralysis had raised millions of dollars to pay for patient care and laboratory research. But polio cases were reaching record levels, and scientists were no closer to a cure. Frustrated by the slow progress, Basil O’Connor resolved to recruit fresh talent to the cause. He soon found what he was looking for in a young and energetic researcher named Jonas Salk.In 1951, Salk began testing a killed virus polio vaccine on monkeys in his Pittsburgh lab. His research soon put him at odds with the leading polio scientist Albert Sabin, who wanted his own live virus vaccine formula to prevail. As their rivalry escalated, Salk prepared to take the risky step of testing his vaccine on human subjects.Be the first to know about Wondery’s newest podcasts, curated recommendations, and more! Sign up now at https://wondery.fm/wonderynewsletterListen to American History Tellers on the Wondery App or wherever you get your podcasts. Experience all episodes ad-free and be the first to binge the newest season. Unlock exclusive early access by joining Wondery+ in the Wondery App, Apple Podcasts or Spotify. Start your free trial today by visiting wondery.com/links/american-history-tellers/ now.See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Hey, history buffs, if you can't get enough of the captivating stories we uncover on American history tellers, you'll love the exclusive experience of Wondry Plus. Dive even deeper into the past with ad-free episodes, early access to new seasons, and bonus content that brings history to life like never before. Join Wondry Plus in the Wondry app or on Apple Podcast and embark on an unparalleled journey through America's most pivotal moments. Imagine it's late in the day in December 1949. You're the director of the National Foundation.

for infantile paralysis, and you're hunched over to your typewriter in your Manhattan office. It's already dark, but you're too busy firing off memos to your department heads to go home yet. You look up as a man with a shock of white hair enters the room. It's Albert Saban, the leading polio researcher from the University of Cincinnati. Oh, Dr. Sabin, what brings you here? A new breakthrough in the lab, I hope? No, I need you to explain yourself. Dr. Savan throws your foundation's latest pamphlet on your desk. The words, polio can be conquered are printed across the cover.

Well, explain what? Polio can be conquered. Yes, but you're telling people that victory over the disease is imminent. It is certainly not. There are no guarantees that polio will be conquered soon or ever. This messaging is irresponsible. Dr. Saban, I'm running a multi-million dollar charity, not a scientific journal. The foundation needs to raise public hopes to encourage donations.

Donors need to know that their dimes are helping to pave the way for a vaccine. and it seems to me that some of the latest research developments are very encouraging. Oh, what do you know about research? You may know public relations, but science is a different matter. It cannot be rushed. You pound your fist against your desk, anger rising in your chest. Oh, it can't be rushed, huh? You think the 40,000 Americans who suffered from polio this year alone would agree that there's no rush?

This has been the worst year for polio on record. And I owe it to the American people to pursue a vaccine as quickly as possible. and I owe it to the people to make sure they get the most safe and effective vaccine possible. I won't sit back while bureaucrats run this process. Has it occurred to you that bureaucrats like me are the only reason you and your friends have any money to pursue your research? Well, maybe so, but at least I'm not shamelessly deceiving the public. With a grimace, Sabin turns around and walks out of your office. You lean back in your chair and make a promise to yourself.

From now on, you're going to back researchers who understand that nothing, is more urgent than developing a vaccine, so you can finally stop polio for good. From Wondery, I'm Lindsay Graham, and this is American History Tellers, Our History, Your Story. In December 1949, leading polio researcher Albert Sabin lashed out at Basil O'Connor, the director of the National Foundation of Infantile Paralysis or NFIP, for publicly claiming that polio would soon be defeated. More than two decades had passed since Franklin Delano Roosevelt recruited O'Connor to lead the fight against polio. His foundation had raised millions of dollars to pay for patient care and laboratory research,

but scientists were still no closer to developing a vaccine that would stop the spread of the disease. And with polio outbreaks on the rise, O'Connor's patients was wearing thin. And in a time before the federal government played a major role in public health, the privately funded NFIP had complete authority over the battle against polio. And as the man steering the ship, O'Connor was determined to speed, up development of a vaccine, but he would have to grapple with a simmering feud between two scientific rivals who clashed over how to put an end to polio's cruel reign. This is episode two, beyond the microscope. By 1946, Basil O'Connor was fed up with the slow pace of polio research. Despite

rising cases, scientists were no closer to finding a vaccine that could prevent the spread of the disease. So that October, he appointed neuroscientist Harry Weaver as the NFIP's first direct director of research with the aim of streamlining the Foundation's research agenda. Weaver was a bold, pragmatic administrator who was determined to transform polio research from a patchwork of scattered academic studies into a focus campaign for a cure. Because as director, Weaver was appalled by how many of the scientists and research labs that received grants from the NFIP were motivated by academic curiosity rather than the desire to save lives. So he revamped funding policies to reward results and cut dead weight, and the identified financial barriers that had stalled progress

and developed creative solutions like overhead allowances to help universities cover indirect costs. Weaver had become convinced that only a vaccine could stop polio, but he soon learned that many scientists bristled at the idea of the NFIP directing their research, even though the organization was their chief source of funding. They saw the foundation officials as fundraisers and PR professionals who had no business weighing in on scientific matters. So Weaver set out to recruit younger, less-established scientists who shared his urgency and were willing to do the work that he deemed necessary. One of them was a young researcher named Jonas Salk.

Salk was born in New York City in 1914 to working-class Russian Jewish immigrants. He sped through his studies, entering high school at age 12 and the City College of New York at age 15. He found direction at NYU Medical School, one of the few local medical schools in the 1930s that did not have quotas capping Jewish students. There, he discovered his passion for lab work and vaccine research, studying under his mentor, virologist Thomas Francis Jr. Then after graduating in 1939, Salk interned at Manhattan's Mount Sinai Hospital, a highly coveted position that one of his friends likened to playing baseball for the New York Yankees. A few years later, in 1941, he secured a fellowship working under Thomas Francis, who had begun running influenza vaccine experiments at the

University of Michigan. This position helped Salk obtain a deferment from serving in the Army during World War II because during the war, the health of America's troops became a major priority, and the U.S. Army was able to recruit Francis to develop an influenza vaccine. At the time, most virologists favored what are known as live virus vaccines containing a weakened version of the actual virus they're trying to inoculate against. These vaccines trigger mild infections that leave the body with lasting immunity. And by the 1914, scientists had successfully developed live virus vaccines for other diseases like smallpox and yellow fever. But in his research on influenza, Salk's mentor Francis favored a different approach.

He believed that immunity did not require a natural infection in the body, arguing that a killed virus vaccine, containing an inactive virus, could safely trick the immune system into producing protective antibodies. He insisted that killed virus vaccines were faster and easier to develop. And unlike live virus vaccines, there was no risk of a properly prepared, killed virus replicating and reverting to its original virile form. So he focused on experimenting with different methods for inactivating the influenza virus. And working together in Ann Arbor, Michigan, Francis and Salk tested killed virus flu vaccines on thousands of U.S. soldiers with promising results. But over time, the relationship between the two men frayed. Francis valued restraint, while Salk was anxious to innovate. Salk later reflected,

I wanted to do independent work, and I wanted to do it my way. So in 1947, Salk accepted a role as the director of a new virus research program at the University of Pittsburgh. The job had little status. The university did not have a reputation as a major research institution. Salk's new quarters were cramped basement rooms in the city's municipal hospital with little staff and no graduate students. Still, Salk was eager for the chance to lead his own research. And in December 1947, the director of research for the NFIP, Harry Weaver,

visited Salk in his Pittsburgh lab as a part of his mission to find new talent to develop a polio vaccine. Weaver knew that over the years, scientists had isolated dozens of strains of polio virus from patients. They had seen that many of the strains were so closely related that immunity

to one protected against the rest. This meant they belonged to the same virus type. But scientists did not know exactly how many types of polio existed. If polio was like smallpox, which had just one type, the task of creating a vaccine would be relatively simple. But if polio was like the flu, which had several different types, developing a vaccine would be much more difficult. So to move forward, Weaver knew that scientists needed to solve two main problems. First, they needed to identify the different

types of polio virus. And second, they needed to produce a safe and consistent supply of each type for use in a vaccine. But the leading scientists advising Weaver had no interest in doing the tedious work of identifying poliovirus times, which required a lengthy process of elimination. Even Weaver admitted, I know of no problem in all the medical sciences that was more uninteresting to solve, but he still hoped that Jonas Salk might be just the man for the task. Imagine it's December 1947 in Pittsburgh, Pennsylvania. You're the research director for the National Foundation of infantile paralysis, and you're walking through the basement of the city's old municipal hospital. You push open a door and step inside a dark and cramped laboratory, where you find a man in a white

lab coat hunched over a microscope. Excuse me, Jonas Salk? As you approach, you notice his stick-rimmed glasses and receding hairline give him a look of authority beyond his years. He looks up from his work with a questioning stare. Yes, how may help you? Well, good afternoon. I'm with the National Foundation of Infantile Paralysis, and I'd like to know what you know about. about polio, Dr. Salk. Oh, well, not much, I'm afraid. My research is in influenza. And how's that going?

You scan the bare-bones lab, your eyes falling upon a leak in the ceiling. Salk follows your gaze. Well, yeah, it's been a struggle, I'll admit. I can't seem to get the university to respond to my requests for equipment or staff. Well, maybe I could help you with that. That is, if you agree to work on polio.

The National Foundation is launching an ambitious project next year. Yeah, what type of project? Well, if a vaccine is ever going to work, it will need to protect people from every type of polio virus. So someone needs to go through the hundreds of samples of the virus and classify them by type. Saul crosses his arms. Oh, virus typing, huh? Grunt work. I didn't move my family all the way to Pittsburgh to become a bean counter, sir. Well, it might not sound glamorous, but I believe I can make it worth your while.

This project has the potential to lead to something much bigger, and it will come with a substantial annual grant from the National Foundation. foundation. You point to the leak in the ceiling. And if you don't mind me saying, it looks like you could use the money. Well, how much are we talking about? I could start you with $150,000 in the first year, and we'll see how we go from there. Salk's eyes widened, his face lightning up with unmistakable excitement. 150. Well then, yes, count me in. You step forward to shake Salk's hand, a grin spreading across your face. You're thrilled to find a scientist hungry enough to do your bidding, performing the painstaking work that will finally lay the groundwork for a vaccine.

Jonas Salk had little interest in studying polio. He had never researched the disease or even attended a conference on the subject. And he knew that virus typing was dull and repetitive work that would take years to complete, the kind of work that more senior scientists typically passed on to graduate students. But the 33-year-old Salk agreed to join the polio. Typing Project after Weaver offered him a generous multi-year grant to expand his staff and facilities. Beginning in 1949, Salk's team worked seven days a week, passing 196 strains of polio virus through rhesus monkeys shipped in from India. Salk and his team injected the monkey's

brains with fecal samples from human polio victims. And once the animals were paralyzed from the disease, the researchers euthanized them, then harvested the virus from their nerve tissue. Roughly 17,000 monkeys would be sacrificed for the virus-typing project alone. Next, they inoculated healthy monkeys with tissue samples of known virus strains. Once they had established immunity, they exposed the monkeys to unknown strains. If they prove vulnerable to infection, it meant the unknown strains belonged to a different type of poliovirus than the type they had been inoculated with. It was an exhausting process of elimination, one that demonstrated Sox's lowly status among researchers.

But although he did not have the credentials of other scientists in the polio field, Harry Weaver appreciated his ambition, reflecting Salk thought big, he wanted to leap, not crawl. And Salk pushed his staff to their limits, too, putting intense pressure on them to take that leap with him. But while Salk was working away on his typing project, another team of researchers grappled with the second obstacle to a polio vaccine, how to produce a safe and plentiful supply of the virus. In the early 1900, scientists had developed the ability to grow and nurture living cells in vitro, outside their human or animal hosts. But early polio experiments showed that polio could only grow in nervous tissue.

This presented a major problem, because the nervous tissue of monkeys was known to cause dangerous inflammation of the brain and spinal cord when injected into humans. But in 1948, Harvard scientist John Enders decided to test a hunch. He hypothesized that since poliovirus could also be found in the gastrointestinal tract, then it had to grow in other parts of the body besides nervous tissue. He put this idea to the test, placing strains of poliovirus in flasks of monkey kidney tissue, and to his delight, the virus thrived. In January 1949, Enders published his results,

announcing that scientists could create a safe, abundant source of poliovirus by growing it in kidney tissue. This was a breakthrough, overturning decades of conventional wisdom, one that one-enders and his colleagues the Nobel Prize. So now, researchers like Salk had a safe method for growing polio virus, and that would allow them to produce enough virus to make a vaccine. But while scientists were unraveling the mysteries of polio in their labs, the disease continued to claim more victims. 1949 was the worst year on record, with 42,000 cases reported across America. The most devastating outbreak was in the West Texas town of San Angelo, which saw 400 cases. Residents there took desperate measures, purchasing fogging trucks to spray the streets with the pesticide DDT, even though scientists had proved that insects did not spread the virus.

Local hardware stores hawked their own formulas of insecticide. Companies sold polio insurance, and some unscrupulous chiropractors alleged that their services could offer immunity. By the time the outbreak ended, 84 San Angelo residents were paid. paralyzed, and 28 were dead. All across the country, Americans lived in fear of an epidemic like San Angelo's. And that summer, Life magazine described polio as the nation's leading public health threat, a sudden and capricious disease that was worst of all, uncontrollable. But two years later, there was finally cause for celebration. In 1951, Saul completed his typing project. He confirmed that there were three types of polio virus. Type one was the most common,

representing 82% of cases. Type 2 made up 10% of cases, and type 3 made up the remaining 8%. Salk and his team had demonstrated that for a vaccine to be successful, it would have to protect against all three types of polio virus. At long last, the main scientific obstacles to developing a polio vaccine had been removed.

Scientists had identified three types of polio virus and learned how to safely grow each one of them. These breakthroughs raised hopes that polio could finally be conquered, But with lives at stake, Basil O'Connor feared a vaccine would still not come soon enough. So he was all to fund the scientist who would stop at nothing to fast track a cure. Hello, American History Tellers, listeners. I have an exciting announcement. I am going on tour, coming to a theater near you.

The very first show will be at the Granada Theater in Dallas, Texas on March 6th. It's going to be a thrilling evening of history, storytelling, and music with a full band behind me as we look back to explore the days that made America. And they aren't the days you might think. Sure, everyone knows July 4th, 1776, but there are many other days that are maybe even more influential. So come out to see me live in Dallas, or for information on tickets and upcoming dates,

go to American History Live.com. That's American History Live.com. Come see my Days that Made America Tour live on stage. Go to American History Live.com. In the summer of 1951, Jonas Salk traveled to Copenhagen, Denmark to report his breakthrough in classifying the different polio strains at an international conference. NFIP research director Harry Weaver arranged the presentation in the hope that it would mark Salk's rise in the field. But at the time, most elite virologists still regarded Salk as

an outsider and a scientific lightweight. Few underestimated Salk's abilities as much as Albert Saven, a longtime polio researcher at the University of Cincinnati. Sabin had helped oversee the virus typing project, and Salc and Savin traveled to the conference together. Salk reflected, during the voyage, it became obvious that I was a nice young whippersnapper from Pittsburgh, going to Denmark to report on some drudgery I had performed. I might have failed abysmally. It seemed clear if Albert had not been pulling the strings and setting the standards. Albert Sabin was born in Poland, but moved to New Jersey at age 15, fleeing violence that erupted after World War I. He rose from humble immigrant roots to become one of America's foremost virologists. He was a brilliant and highly dedicated

scientist, but he was also competitive, arrogant, and abrasive. One researcher described him as a mean goddamn bastard. Another colleague declared, All Us Who Know Albert, admire him and detest him at the same time. But no one could besmirch his work on polio. Sabin saw the impact of polio firsthand in 31, treating patients in New York City's Bellevue Hospital during a major epidemic. Four years later, Sabin joined the prestigious Rockefeller Institute, where he gained a reputation for his work ethic and his ego. Absorbing lessons from his mentors, he became convinced that true immunity against polio required a live virus vaccine, one that was strong enough to generate lasting antibodies

yet too weak to cause serious disease. In 1939, Sabin left the Rockefeller Institute to run his own lab at the University of Cincinnati, There he had performed a series of autopsies on polio victims that demonstrated that the virus lived in the digestive tract, not the nasal passages, as previously believed. This was a crucial discovery that helped crack the code of how polio operates in the body. And having immersed himself in the field, he firmly believed that vaccine development should be led by scientists like himself and not fundraisers and administrators like Basil O'Connor and Harry Weaver. In December 1949, he admonished O'Connor for declaring that the conquest of Polaro

Polio was now in sight in an NFIP fundraising pamphlet. Sabin was afraid that the claim could mislead the public. He told O'Connor that there was no assurances of ever preventing polio and said that he was irresponsible for suggesting otherwise. But O'Connor had his own priorities as director of the Foundation. In the two decades since he had taken the lead in the campaign against polio, he had become a powerhouse organizer and fundraiser. He had risen far above his working-class routes,

with his Park Avenue home and memberships to New York, York's most exclusive clubs. He hung a large portrait of himself across from his desk, and every day he wore a fresh carnation in the lapel of his tailored pinstriped suits. Despite cutting a flashy first impression, though, few could rival his work ethic. He was known for his long hours, harsh memos, and intolerance for inefficiency. But in a sad twist of fate, the war on polio became personal for O'Connor in 1950, when his daughter Betty Ann called him and told him, I think I've got some of your disease.

The 30-year-old mother of three was almost fully paralyzed on her left side. After months of rehabilitation, she regained movement everywhere except her abdomen, where a set of muscles was permanently destroyed. After this, O'Connor was more determined than ever to conquer polio, and in September 1951, he traveled back from the Denmark Polio Conference with Harry Weaver on the luxury ocean liner the Queen Mary. While on board, Weaver introduced O'Connor to fellow passenger Jonas Salk. As they sat down to dinner, O'Connor was moved by Salk's compassion for Betty Ann.

He believed he had finally found a scientist who cared about how his research impacted the lives of ordinary people, explaining Salk sees beyond the microscope. With his flamboyant style and brusque manners, O'Connor often clashed with scientists, but in Salk's case, the two became fast friends. They were both driven perfectionists who viewed the fight against polio as an urgent problem, a race against time that they could not afford to lose. So after returning to Pittsburgh, Salk began developing a killed virus vaccine, using the same approach as the influenza vaccine he worked on with his mentor Thomas Francis during

World War II. He used a new $200,000 grant from the NFIP to further expand his lab and staff. And unlike most researchers in the field, they worked inside a hospital that had a large polio ward with a constant sight of polio patients, serving as a reminder of the state. for their research. Salk and his team began their experiments by using monkey kidney cells to grow large quantities of pure undiluted poliovirus. Then Salk chose strains for each of the three types of poliovirus. Some strains of the virus were more virulent, while others were weaker. In the end, Salk chose to use potent strains that he believed would be strong enough to trigger immunity,

confident that he could safely inactivate or kill them so they would do no actual harm. For type 1, the most common type of polio virus, Salt chose the extremely virulent Mahoney strain, named after the Akron-Ohio family it had afflicted. It was so strong that it had killed three children who lived next door to the Mahonis. And in monkeys, the Mahoney strain caused paralysis and death more often than any other type 1 strain. Next, Salk and his team use formaldehy to inactivate the virus strains in a meticulous process he had perfected over years of trial and error. Finally, they injected the killed virus into monkeys and watched them for signs of polio.

If one got sick, it meant that they had failed to properly inactivate the virus, and the entire batch of vaccine was destroyed. But the results were promising. The monkeys did not get sick, and blood tests show that their polio antibodies had multiplied. So after the success of these monkey experiments, Salk began contemplating his next step, human testing. In an era before widespread government involvement in public health, the NFIP had total control of all funding for polio vaccine research and development.

And while Salk was running his experiments on monkeys, Administrator Harry Weaver formed a 12-member immunization committee to advise him on the development and testing of a polio vaccine. It had no real authority, its role was purely advisory. The committee members included killed virus vaccine advocates like Salk and his mentor Thomas Francis, but most of the committee supported live virus vaccines, including Albert Sabin. In December 1951, this immunization committee met to review Salk's experiments on monkeys. Salk spoke about how his killed virus vaccine had produced a powerful antibody response.

None of the monkeys he injected had contracted polio or experienced an adverse reaction. But most of the committee was skeptical that a killed virus could induce strong, lasting immunity. And they worried about the potential dangers of using such potent strains, especially the Mahoney strain if something went wrong and the virus was not. not properly inactivated. Sabin affirmed that a live virus vaccine was the only approach to consider. He had a vested interest in the fight, having spent years working toward his own live virus vaccine. Weakening live polio viruses was far more complex than killing them, though, and he knew it would take longer to perfect, but he believed a live virus vaccine would be the best method for protecting

people against polio. The other members of the committee agreed with Sabin, and they refused to recommend that Salk moved forward with human testing. Little did they know, Salk had already begun to put his plants into motion. Imagine it's January 1952 in Leedsdale, Pennsylvania, and you're walking through the frozen grounds of the D.T. Watson home, where your 15-year-old son, Matthew, is a resident. You and your wife placed Matthew here five years ago after polio left him paralyzed from the waist down. But today, walking beside you is a scientist named Jonas Salf. He clasps his gloved hands behind his back and then turns to face you. So did the staff explain to you that I work in polio research? Yeah, I heard something about that. Is there something you can do for our son?

No, not exactly. You see, I've been working hard on a new polio vaccine. I believe it to be highly effective, but to move forward, I need to test it. And I'm hoping you'll give your permission to let me vaccinate your son. You stop walking, your throat suddenly feeling tight. Well, now, I don't understand. Matthew already had polio. Yes, and that's what makes him a perfect test-up. subject. There's absolutely no risk of him getting polio from the vaccine. Matthew's body has already fought the virus. He has antibodies in his blood. So you're going to give him the virus again, an inactivated version of the virus. I'll take a blood sample from Matthew to make sure he gets the same antibodies that are already in his system. But this will help me determine the best

preparation of the vaccine. It may even strengthen Matthew's immunity to future infections. I assure you, there is little risk involved here. Well, that's easy for you to say. I don't know about letting my son be experimented on it. He's already been through so much, you know. Yeah, I understand. I have three sons of my own, and I've seen what polio does. But this would give you a chance to help make sure that no more fathers have to watch their children suffer from this terrible disease. There's something in salk's steady gaze and earnest manner that makes you believe he truly means it. Well, all right, if it's really going to help, then, yes, you have my permission. Thank you. I promise you, your son is going to help save lives.

You're about to walk back to your son's dormitory when Salk holds up a hand to stop you. Oh, one more thing. Please don't speak to anyone about this, not the papers, not even the other parents. We have to be certain before we tell the world what we're doing. Salk turns his collar to the wind and then walks away. Across the yard, a nurse leans over a young boy, adjusting his leg brace. It feels like only yesterday that the doctors told you that your son would never walk again. Holio is a terrible disease, and you pray you're doing the right thing.

by your boy and everyone else's. In early 1952, Jonas Salk began looking for human test subjects for his vaccine. First, he went to the D.T. Watson home for crippled children outside Pittsburgh, where he gained permission from parents of children who had been disabled by polio. Next, he went to Pennsylvania's Polk School, an overcrowded institution for boys and men with severe intellectual disabilities, many of whom were long-term wards of the state. Officials there were initially reluctant, but a recent polio outbreak at the school convinced them that the experimental vaccine could be a useful safety measure.

Because the Polk School was a state institution, though, Salk also needed the state's approval. Pennsylvania officials approved the trials, but asked him to obtain parental consent wherever possible. But Salk's surreptitious trials were only known to Basil O'Connor, Harry Weaver, and NFIP science director Tom Rivers. The fellow scientists on the immunization committee were left in the dark. Privately, Rivers was troubled by the thought of testing

an experimental vaccine on institutionalized children, many of whom lacked real parental protection. He recalled, an adult can do what he wants, but the same does not hold true for a mentally defective child. Many of these children do not have any mamas or papas, or if they did, their moms and papas didn't give a damn about them. But in the 1950s, human testing operated with few ethical standards or regulations. Researchers often use orphans, institutionalized children, and prisoners as test subjects. And in the end, Rivers and his colleagues, at the National Foundation believed in the promise of Salk's vaccine. Ignoring the warnings of their leading grantees,

they decided it was time to take the risky step of testing Salk's vaccine on humans. They knew the stakes were high. This experiment could make or break their entire crusade against polio. In June of 1952, Jonas Salk began testing his killed virus vaccine at the D.T. Watson home near Pittsburgh. He believed the risk was minimal because all the test subjects were recovering polio patients. So Saul conjected each subject with a formula matching the virus type of their existing antibodies to see if blood tests showed a significant rise in antibody levels.

The first to be vaccinated was Bill Kirkpatrick, a 16-year-old former athlete who walked with braces after polio had left him paralyzed the previous year. His parents were reluctant to give their permission, but Kirkpatrick himself had insisted on it, driven by thoughts of a fellow polio patient named Peggy whom he had befriended in the hospital. She sent him a rose that he tucked away under his pillow, but when he was well enough to write her a thank-you note, it was promptly returned with a stamp declaring she was deceased. So a year later, Kirkpatrick was determined to protect others from a similar fate. He and the other participants gathered in an auditorium at the Watson home, where a table was set out with hypodermic needles, cotton swabs, and rubbing alcohol. Salk administered 52 injections

and monitored the children closely for potential side effects and signs of polio, later admitting he didn't sleep well for months. The initial signs were encouraging, though, so Salk began his next round of vaccinations at the Polk School. These experiments were riskier, because unlike at the Watson home, most of the residents at the Polk School had never had polio. But almost immediately, the results were striking.

None of the test subjects experienced adverse side effects. Salk had demonstrated that the vaccine was, both safe and effective. Blood tests of vaccinated participants showed that it had generated antibodies against all three types of polio virus, meaning that those who received the vaccinations were now protected against polio.

Salk called that moment the thrill of my life. But Salk also understood that he was in a race against time. That year, 1952, was the worst year for polio in the nation's history, with more than 52,000 cases across the country. Of those, 21,000 people experienced, in some form of permanent paralysis and roughly 3,000 died. And while some polio outbreaks began around Memorial Day and faded by Labor Day, the 1952 season was unusually long, beginning in

the spring and pushing well into October. One family in the Iowa Farm Belt saw 11 of their 14 children fall ill despite every precaution. In Milwaukee, a family lost four of their six children in the span of just six days. Despite modern drugs and technology like Iron Long, lungs, doctors felt powerless. And though in that same year, the NFIP had raised a record $41 million in its annual March of Dimes campaign, the need was so great that 500 local chapters went bankrupt after expending all their funds on patient care. The speed with which polio devastated families showed that even prompt medical attention offered no guarantee of survival. Only a vaccine could slow the death toll. Few felt the urgency of the battle against polio more fiercely.

than Basil O'Connor. In 1952, he turned 60 years old, and that summer, he suffered a major heart attack. But rather than slow down, O'Connor pushed even harder. Jonas Salk reflected, I think he wants to make sure we lick this thing while he's still alive. So in January 1953, O'Connor staged a meeting of the National Foundation's Immunization Committee in Hershey, Pennsylvania. At this gathering, Salk presented the results of his experiments at the Watson home and Polk School. O'Connor was hoping he could persuade the scientists on the committee to endorse a larger field trial, but many remain skeptical. Imagine it's January 1953 in Hershey, Pennsylvania.

You're a virologist from Walter Reed Army Hospital and a member of the NFIP's Immunization Committee. You and your fellow committee members are gathered around a long table in a wood-paneled conference room on the old Hershey estate. The young researcher Jonas Salk has just finished presenting the results of his vaccine experiments and a heavy silence hangs in the air. You clear your throat, cutting through the tension. Well, gentlemen, I for one, am impressed with Dr. Salk's data. So I say we begin preparations for a larger field trial, and the sooner the better. Across the table, Albert Sabin leans forward, glaring at you with obvious disdain. You all know I'm not one to criticize the work of a fellow scientist, but I cannot support any killed virus vaccine, especially one that uses such a virulent strain,

injecting children with a Mahoney strain that's simply unthinkable. Well, Dr. Saban, I'm by no means a fan of the killed virus approach, and I think we can agree that live virus vaccines are the gold standard. But I believe the consequences of inaction outweigh the risks.

Well, yes, let's talk about those risks. How do we know Dr. Salk's inactivation process is foolproof? Do we really know that it's safe to inject children with monkey kidney tissue? Why use the Mahoney strain when less virulent options are available? I simply don't understand the hurry. Why rush into field trials with an unfinished product?

You sneak a glance at Basil O'Connor, who looks ready to explode, then sit up a little straighter. Well, Dr. Saban, this vaccine, it may not be the final answer, but we cannot afford to wait. People are dying out there. Be that as it may, this committee must not allow the foundation to hijack the scientific process. I won't let America's children be used as guinea pigs for a potentially dangerous product. I think it's time we had a vote. Raise your hand if you approve of initiating field trials. Your hand shoots up. Dr. Salks and his mentor Tom Francis follow suit.

Savans' lip curls and satisfaction. All right, raise your hand if you think it's still too dangerous to endorse a large field trial. Much to your dismay, the other nine members raised their hands. Then it's decided. Meeting adjourned, I guess. As most of the committee members gather up their things, Saul closes his eyes and sinks into his chair. You can't help but share his disappointment. You're starting to fear that if scientists continue to set their own pace,

there will never be a vaccine to end polio. In January 1953, the NFIP's Immunization Committee debated the merits of Jonas Salk's vaccine and the question of whether the foundation should pursue a larger field trial. Salt recalled, it was a tense meeting, and I was by no means the tensest person there. Shock, alarm, skepticism, jealousy, all spilled out at once. But the Immunization Committee ultimately would not have the last word. Up until then, Salk had succeeded in keeping his work largely out of public site. Typically, scientists did not publicize work until it appeared in a scientific journal.

But a few days after this committee meeting, Harry Weaver addressed the Foundation's Board of Trustees and hinted at a promising new development with a killed virus vaccine. Though he gave no details, a reporter familiar with Salk's research identified him as a reason for Weaver's optimism and named him in a Pittsburgh newspaper article. Word quickly spread. On February 9, 1953, Time magazine announced some solid good news on the polio front. A photo of Salk was published alongside the caption, Ready for the Big Attack. Albert Saven was appalled. In a letter to Salk, he wrote, although it was nice to see your happy face in time, the stuff that went with it was awful. He blamed the NFIP for making unwarranted and premature promises and

warned Salk to be careful. The Foundation had broken scientific tradition by publicly discussing unpublished work. Sabin and other colleagues urged Salk to prioritize scientific protocols over pressure from the Foundation and the public. But SABin was also a rival with his own agenda. He saw polio research as a zero-sum game and wanted his live virus vaccine to prevail. And despite Sabin's warnings, the NFIP depended on news of scientific progress to sustain its fundraising. So when February 1953, O'Connor hosted a gathering of elite journalists and medical

officials at New York's Waldorf Astoria Hotel. Salk spoke cautiously about his experiments, but the press seized on the moment and reported that a polio vaccine was imminent. Seeing this, even Salk was horrified. He had yet to publish his results in a scientific journal. And fearing

for his reputation as a scientist, he suggested going on national radio to speak directly to the public. O'Connor readily agreed, welcoming the public. And on March 26, 1953, millions tuned into a CBS broadcast in which Jonas Salk presented his preliminary findings but urged patients. Despite his best efforts, though, he failed to temper public expectations. The press began touting the promise of what they referred to as the Salk vaccine. A few weeks later, O'Connor announced the formation of a vaccine advisory committee

to begin planning a large-scale field trial. He deliberately excluded other foundation grantees who oppose Salk's vaccine like Albert Saban. Weaver explained, we formed it to break a logjam, and O'Connor declared, the researcher's word is law in the laboratory, but sometimes you have to point out to him what's happening outside the lab window.

And as far as O'Connor was concerned, outside the lab, the foundation's word, was law. The NFIP had total control of all funding for polio vaccine development, and now they were going to put it to use. For O'Connor, the question was no longer if Salk's vaccine would be mass-tanked, but when? Because he had decided it was finally time to launch the largest medical experiment

America had ever seen to finally beat polio. From Wondery, this is episode two of our three-part series on Conquering Polio from American History Tellers. In the next episode, field trials begin for the Salk Polio vaccine involving nearly two million children and several hundred thousand adult volunteers. And President Dwight D. Eisenhower faces new demands for the federal government to take responsibility for getting the vaccine to the public. If you like American History Tellers, you can binge all episodes early and ad-free right now by joining Wondery Plus in the Wondry app or on Apple Podcasts. Prime members can listen ad-free on Amazon Music.

And before you go, tell us about yourself by filling out a short survey at Wondry.com slash survey. American History Tellers is hosted, edited and produced by me, Lindsay Graham for Airship. Audio editing by Mohamed Shazib. Sound designed by Molly Bog. Music by Thrum. This episode is written by Ellie Stanton, edited by Dorian Marina, managing producer Desi Blaylon. Senior producers are Alita Ruzanski and Andy Beckerman. Executive producers are Jenny Lauer Beckman and Marsha Louis for Wondering.