Jonas Salk and the Polio Vaccine: The Science, the Sacrifice, and a Patent He Never Filed

Ask anyone who grew up in the 1940s or 1950s what they were most afraid of as a child and you'll likely hear the same answer: polio. Not war, not poverty, not the dark. Polio. It was a disease that crept in silently each summer, striking children at random, leaving some with withered limbs and others sealed inside a metal cylinder known as the iron lung, fighting to breathe. Parents emptied swimming pools. Schools cancelled sports days. Whole neighbourhoods held their breath.

The technical name was poliomyelitis, a virus that targeted the motor neurons of the spinal cord and sometimes the brainstem, robbing children of movement, independence and, too often, their lives. At its peak in 1952, the United States alone recorded more than 58,000 cases in a single year.

Then Jonas Salk came along and changed everything.

Dora Press Salk and Daniel Salk with sons Herman, Jonas, and Lee. Jonas inherited his mother’s work ethic and learned how to maneuver around her iron will, a skill that would help him later when confronted by the politics of science; Jonas Salk had few fond memories of childhood. By the time Jonas entered high school, he was a driven, focused, serious individual.

A Kid From the Bronx Who Didn't Care Much for Biology

Jonas Edward Salk was born on 28 October 1914 in New York City, the eldest son of Orthodox Jewish immigrants from Poland. His parents had no formal education to speak of, but they were determined that their boys would. They pushed Jonas and his brothers relentlessly, and it paid off: Jonas enrolled at the City College of New York at just fifteen.

Ironically, biology bored him. He had little interest in dissecting frogs or memorising organ names. What fascinated him was people: how they thought, how they behaved, and how fragile the human body really was. He once described his own motivation in characteristically plain terms: "I was merely interested in things human, the human side of nature, if you like, and I continue to be interested in that."

His first plan was law school, until his mother pointed out that if he couldn't win an argument with her, he stood no chance in a courtroom. He took the hint, switched to medicine, and enrolled at New York University School of Medicine, where he graduated in 1939.

From Flu Shots to Polio: Learning to Kill a Virus

During World War Two, Salk worked alongside his mentor Dr Thomas Francis at the University of Michigan, helping to develop a killed-virus influenza vaccine for the US military. It was here that Salk first tested an idea his peers thought was borderline reckless: that you didn't need a live virus to build immunity. A dead one, treated carefully, could do the job without any risk of actually infecting the patient.

In 1947, he took up a post as director of the Virus Research Laboratory at the University of Pittsburgh School of Medicine, and turned his attention to polio. The work began unglamorously: his first task was simply to catalogue the different strains of poliovirus. By 1951, the team had confirmed there were three distinct types, and all three would need to be covered by any vaccine worth making.

Dr Salk in his lab

Funding came from the National Foundation for Infantile Paralysis, the charity established by Franklin D. Roosevelt, who had himself contracted what was widely believed to be polio in 1921 at the age of 39. Roosevelt's illness left his legs permanently paralysed. You might know the foundation today as the March of Dimes.

Salk's approach was simple in principle, brutally difficult in execution. He used formaldehyde to kill the poliovirus completely, preserving just enough of its structure to trigger an immune response without any risk of causing the disease. His critics weren't shy about their doubts. The prevailing scientific view held that only a live virus could produce lasting immunity. Salk disagreed, and he intended to prove it.

The Polio Pioneers: The Largest Medical Trial in History

Before the big trial, Salk moved carefully. On 2 July 1952, he injected 43 children at the D.T. Watson Home for Crippled Children in Sewickley, Pennsylvania. These were children who had already recovered from polio. He wasn't giving them anything new: he was checking whether the vaccine raised their antibody levels. It did, with no ill effects.

Soon after, he vaccinated children who had never had polio. Then he vaccinated himself, his team, his wife, and his three sons.

By 1954, the trial had gone national. What followed was the largest medical experiment in history at that point: 1.8 million children across 44 US states, plus Canada and Finland, took part. Those who received the vaccine became known as the Polio Pioneers. Around 440,000 received the actual vaccine. Roughly 210,000 got a placebo. Another 1.2 million were observed as controls.

The results were announced on 12 April 1955, a date chosen deliberately. It was the tenth anniversary of the death of Franklin D. Roosevelt, whose paralytic illness had made him the most famous face of the disease. Thomas Francis, Salk's former mentor and the director of the trial, declared the vaccine safe, potent, and around 90 per cent effective against paralytic polio. The news broke at a press conference at the University of Michigan, and by that afternoon the US government had licensed the vaccine.

President Eisenhower summoned Salk to the White House Rose Garden and called him a "benefactor of mankind." The whole country, it seemed, exhaled at once.

April 23, 1955: Dr. Jonas Salk, who developed the vaccine that is believed to have struck the death knell of polio, as he received a special citation from President Dwight David Eisenhower in the White House Rose Garden. The President praised the young doctor as a “benefactor of mankind” and said that his work was in the “highest tradition of selfless and dedicated research.”

The Cutter Disaster: When Things Went Wrong

Victory didn't last long without a serious scare. Within weeks of the announcement, reports began reaching the US Surgeon General of children developing paralytic polio shortly after being vaccinated. The culprit was Cutter Laboratories in California, one of six pharmaceutical companies licensed to produce the vaccine.

It turned out that some batches produced by Cutter, and later by Wyeth and others, had not been properly inactivated. Live poliovirus had made it into more than 100,000 doses. In total, the Cutter vaccine caused 260 cases of polio and killed 11 people. Around 409,000 children had received the faulty batches before the Surgeon General pulled them from use.

An investigation found the problem wasn't with Salk's formula but with production methods that hadn't followed his instructions. The outcome was a complete overhaul of vaccine safety testing in the United States, and the creation of a dedicated technical committee to review all polio vaccine batches going forward. It was a grim chapter, but it ultimately made the whole system safer.

Sabin's Sugar Cube and a Curious Cold War Chapter

While Salk was making headlines, another scientist was quietly working on a rival approach. Albert Sabin believed a live but weakened virus, given orally rather than by injection, would produce stronger and longer-lasting immunity. His vaccine could be dropped onto a sugar cube, which made it far easier to administer to large numbers of children.

Because the Salk vaccine had already been committed to in the United States, Sabin did much of his testing elsewhere. In 1958, a trial involving 20,000 Soviet children took place. By 1959, that number had risen to ten million. The results were clear: Sabin's oral vaccine worked. For his contributions, the Soviet Union awarded him the Order of Friendship of Peoples, described as the country's highest civilian honour. It was a remarkable moment of scientific cooperation in the middle of the Cold War.

By 1961, the Sabin oral vaccine had largely replaced Salk's injected version in many countries, simply because it was cheaper and easier to roll out on a massive scale. Salk and Sabin never got on particularly well, and the rivalry between them was widely known in scientific circles. Salk, for his part, always maintained that a killed-virus vaccine was the safer option. As it turned out, decades later, he was proved right: rare cases of vaccine-derived polio from the oral vaccine eventually led the United States to switch back to an injected inactivated vaccine in 2000.

In 1953, a colleague administers the polio vaccine to its creator, Dr. Jonas Salk.

Could You Patent the Sun?

Despite producing one of the most consequential medical breakthroughs of the 20th century, Salk received neither a Nobel Prize nor a seat at the National Academy of Sciences. Some attributed this to professional jealousy: Salk had a habit of taking credit without always acknowledging the work of others, including John Enders, Thomas Weller, and Frederick Robbins, who had won the Nobel Prize in 1954 for discovering how to grow poliovirus in laboratory tissue, work that made Salk's vaccine possible.

There was also the question of the patent, or rather, the lack of one. When a reporter asked Salk who owned the rights to the vaccine, he gave an answer that has been quoted ever since: "Well, the people, I would say. There is no patent. Could you patent the sun?"

It's a great line, and Salk clearly meant it. But the full picture is slightly more complicated. When the University of Pittsburgh and the National Foundation for Infantile Paralysis actually looked into patenting the vaccine, their own patent attorney concluded that Salk's techniques weren't novel enough to qualify. So while Salk's principled stance was genuine, the decision was also, in part, made for him. Either way, six pharmaceutical companies were licensed to manufacture the vaccine and Salk never profited from any of them. The vaccine reached 90 countries by 1959.

Françoise Gilot and Pablo Picasso in 1948. Gilot was an accomplished artist and Picasso’s muse for nearly a decade. In 1970, Gilot found love with Jonas Salk.

Life After Polio: La Jolla, Françoise Gilot, and the Search for an HIV Vaccine

In 1963, Salk founded the Salk Institute for Biological Studies in La Jolla, California. The building itself is worth a mention: designed by architect Louis Kahn, it's considered a masterpiece of modernist architecture, two mirrored concrete laboratory wings framing a central courtyard open to the Pacific Ocean. DNA pioneer Francis Crick was among its early fellows.

Salk's personal life had its own unexpected turns. He married his college sweetheart Donna Lindsay in 1939 and they had three sons, all of whom went on to work in medicine or science. The marriage ended in 1968. Two years later, Salk married Françoise Gilot, the French artist who had been Pablo Picasso's partner through much of the 1940s and early 1950s, a relationship she had famously documented in her memoir Life With Picasso. The two settled in La Jolla, where Salk continued to work.

The Salk Institute

In his final years, Salk turned his attention to HIV, convinced that the same killed-virus approach that had beaten polio could be adapted for AIDS. He didn't live to see whether he was right. Jonas Salk died of heart failure on 23 June 1995 in La Jolla, California, at the age of 80, still working on the problem.

Where Does Polio Stand Today?

The United States was declared polio-free in 1979. The entire Western Hemisphere followed by 1994. Today, wild poliovirus transmission has been reduced to a tiny handful of cases globally, down from an estimated 350,000 per year in 1988. Pakistan and Afghanistan remain the only countries where wild poliovirus has never been fully interrupted.

But the virus hasn't disappeared entirely, and some of the remaining cases are caused by vaccine-derived strains from the oral vaccine that was once celebrated as Sabin's triumph. One particularly damaging blow to eradication efforts came in 2011, when it emerged that the CIA had used a fake hepatitis B vaccination campaign in Pakistan as cover while searching for Osama bin Laden. The revelation fed conspiracy theories across parts of Asia and Africa that vaccination programmes were Western intelligence operations, making it significantly harder to reach children who needed the vaccine most.

The story of polio is still being written. But thanks to Jonas Salk's stubborn insistence that a dead virus could do what everyone said only a live one could, generations of children have grown up without ever knowing what a summer spent in fear of swimming pools actually felt like. That's not a bad legacy for a kid who found biology boring.

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Sources

1. Salk Institute for Biological Studies. "About Jonas Salk." https://www.salk.edu/about/history-of-salk/jonas-salk/

2. Science History Institute. "Jonas Salk and Albert Bruce Sabin." https://www.sciencehistory.org/education/scientific-biographies/jonas-salk-and-albert-bruce-sabin/

3. World Health Organization. "History of Polio Vaccination." https://www.who.int/news-room/spotlight/history-of-vaccination/history-of-polio-vaccination

4. History of Vaccines. "Jonas Salk, MD." https://historyofvaccines.org/history/jonas-salk-md/timeline/

5. PMC / NIH. "Jonas Salk (1914-1995): A Vaccine Against Polio." https://pmc.ncbi.nlm.nih.gov/articles/PMC6351694/

6. Polio Vaccine field trial detail: PMC. "A Calculated Risk: The Salk Polio Vaccine Field Trials of 1954." https://pmc.ncbi.nlm.nih.gov/articles/PMC1114166/

7. University of Pittsburgh School of Public Health. "The Jonas Salk Legacy at Pitt." https://www.publichealth.pitt.edu/about/history-mission/jonas-salk-legacy-pitt/general-history