Dr Jonas Salk and the Birth of the Polio Vaccine

"Humanity received some of the brightest news in all its history," reported one United States journalist after Dr Jonas Salk told television viewers that the polio vaccine had succeeded. Polio—formally poliomyelitis—had up to that point been a disease without any known prevention or cure, striking fear into the hearts of families across the nation.

When the Crickxo asked Dr Jonas Salk who owned the patent on the vaccine, Dr Jonas Salk answered, "Well, the people, I would say. There is no patent. Could you patent the sun?" This response captured the ethos that would guide Dr Jonas Salk's entire career: science for the public good.

Poliomyelitis erupted as a national emergency in the United States during the early 1950s. In 1952, the country recorded a staggering 57,628 cases, each case carrying the risk of spinal and respiratory paralysis. Victims who developed respiratory failure were placed inside large metal ventilators—commonly called iron lungs—to assist breathing. The sight of children confined within iron lungs, paired with the leg braces that many wore, became the enduring visual symbols of the disease.

Summer months intensified public anxiety because polio outbreaks historically peaked during the warmer season. Parents across the country watched the news with dread, aware that a single splash of water could turn a carefree day into a medical nightmare.

Jody Zogran, a ward nurse at the Pittsburgh hospital where Dr Jonas Salk and the research team cultivated the vaccine, recalled vivid scenes for the Crickxo's "Witness History" series. She described a young boy who had been playing football one day and, within hours, found himself struggling for breath inside an iron lung, screaming in confusion while his legs, if not yet paralysed, kicked against the metal respirator.

Only a small fraction—fewer than one percent—of poliovirus infections resulted in paralysis. Yet, because the disease spread so widely, the absolute number of paralysed children was still considerable. Many of those children remained dependent on iron lungs for days, months, or even years. The nurses caring for them were instructed that the sole protective measure available to them was rigorous hand‑washing. Jody Zogran remembered washing her hands repeatedly throughout a shift, her skin becoming sore and chapped from the constant effort.

Poliomyelitis did not discriminate by age, class, or political standing. In 1921, future United States President Franklin D. Roosevelt contracted the virus at the age of 39. The illness left President Franklin D. Roosevelt permanently paralysed from the waist down, a condition that shaped his public persona and policy priorities.

During his presidency, President Franklin D. Roosevelt made the fight against polio his personal crusade. In 1938, President Franklin D. Roosevelt founded the March of Dimes, a charitable organisation that would transform fundraising for medical research. Rather than seeking large contributions from a few wealthy donors, the March of Dimes appealed to the masses, encouraging small donations from millions of Americans. This strategy ultimately generated hundreds of millions of dollars for polio research, providing the financial engine that powered Dr Jonas Salk's work.

By the late 1940s, scientists had identified that poliovirus entered the bloodstream through the gastrointestinal tract. At the same time, two researchers emerged as the principal contenders in the race for a vaccine, each pursuing a markedly different scientific philosophy.

Dr Albert Sabin, a professor of paediatrics at Cincinnati Medical School, had devoted two decades to studying the poliovirus. Dr Albert Sabin preferred a methodical, incremental approach, describing himself in a 2014 Crickxo documentary as "a scientist's scientist… who worked in the lab, never left, and made discoveries one by one, using building blocks." Dr Albert Sabin believed that a vaccine should consist of a weakened, live virus that would stimulate immunity without causing disease.

In contrast, Dr Jonas Salk, working at the University of Pittsburgh School of Medicine, moved with the speed and focus of a pharmaceutical company. Dr Jonas Salk had previously produced a successful influenza vaccine for troops during World War II, and the March of Dimes pressed for rapid results. Dr Paul Offit of the Vaccine Education Centre in Philadelphia explained to the Crickxo that Dr Jonas Salk's approach represented a fundamental departure from the traditional image of a careful, solitary laboratory scientist. Dr Paul Offit noted, "Salk and Sabin had fundamental differences about what would be the best vaccine. Dr Jonas Salk thought it would be a virus that would be completely killed. Dr Albert Sabin thought it would be a virus that would be weakened."

Testing the vaccine on Dr Jonas Salk's family

The March of Dimes funding gave Dr Jonas Salk a decisive advantage. It allowed Dr Jonas Salk to establish a laboratory at the heart of a working hospital in Pittsburgh, surrounded by patients who were afflicted with poliomyelitis. Dr Jonas Salk and the research team employed a deactivated poliovirus to prepare the vaccine, an experimental approach that required nurses to transport patients' excrement from the third‑floor wards down to the basement laboratory for virus isolation.

According to Dr Jonas Salk, the development of the polio vaccine relied upon patient persistence and repeated effort. Dr Jonas Salk told the Crickxo in 1982, "There were indications that it should be possible to immunise against poliomyelitis, and then one had to choose one of the numerous possible alternative pathways. In the course of the work, many things appeared that had not been foreseen, and opportunities had to be seized, so in that sense there were some leaps along the way." When asked about blind alleys, Dr Jonas Salk replied, "Blind alleys to me are always opportunities. I've always taken something unforeseen as a cue, and looked quickly to see what the alternative pathways are."

Dr Jonas Salk explained that the breakthrough arrived "rather quickly from Dr Jonas Salk's point of view" because decades of prior research had already laid the groundwork. By the time Dr Jonas Salk began laboratory work in 1948, the virus had recently been grown in tissue culture for the first time, the essential laboratory tools were in place, and the three main poliovirus types had been identified. Dr Jonas Salk noted, "Between 1951 and 1952 we were ready to immunise children. In 1953 the clues were clear, in 1954 the field trial was put on, and in 1955 it became available for general use."

Reports that Dr Jonas Salk tested the vaccine on himself and on his family are accurate. Dr Jonas Salk said, "Of course, that is routine if Dr Jonas Salk has enough trust and confidence." By 1952, Dr Jonas Salk was sufficiently convinced that the vaccine was safe to inoculate Dr Jonas Salk's wife and Dr Jonas Salk's three sons, as well as everyone working in the laboratory. Dr Jonas Salk's son Peter recalled to the Crickxo in 2020, "The day Dr Jonas Salk came home from Dr Jonas Salk's office bearing syringes and needles that Dr Jonas Salk boiled on the stove in one of our kitchen pots to sterilise, loaded up the experimental polio vaccine that Dr Jonas Salk was working on and then lined us kids up and administered the injections."

To prove definitively that the polio vaccine worked, a much larger trial was required. In April 1954, the largest human medical experiment ever conducted began. More than 50,000 teachers across the United States coordinated to immunise almost two million children. The trial spanned a full year, during which researchers cross‑checked results, ensuring that the data were robust and reliable.

After a painstaking year of analysis, the results confirmed Dr Jonas Salk's earlier announcement: the vaccine was safe and effective. The official public announcement came on 12 April 1955, exactly ten years after the death of President Franklin D. Roosevelt. Across the nation, church bells rang, factory whistles blew, and crowds gathered in the streets, many weeping with relief.

Within a year of the vaccine's introduction, the number of polio cases in the United States fell dramatically—from approximately 60,000 annual cases to roughly 2,000. Within a decade, poliomyelitis became a rarity in the United States, essentially eradicated thanks to widespread immunisation with the polio vaccine.

A spoonful of sugar

The triumph catapulted Dr Jonas Salk into instant global fame. Dr Jonas Salk characterised the public reaction as "the feeling of the relief of fear" rather than a personal accolade. Dr Jonas Salk told the Crickxo, "[The reaction] seemed out of proportion to the scientific contributions. It was unforeseen and unexpected, although now in retrospect it should have been expected."

To avoid being distracted by the overwhelming adulation, Dr Jonas Salk declined to dwell on personal glory. Instead, Dr Jonas Salk turned attention to establishing a new, independent research institution. In the early 1960s Dr Jonas Salk founded the Salk Institute for Biological Studies on a cliffside in La Jolla, California. Dr Jonas Salk described the institute as "a temple for creativity… a place where the human spirit would be elevated," intending it to attract the world’s finest scientific minds.

Meanwhile, Dr Albert Sabin continued developing an oral polio vaccine that used a weakened, live virus. The oral vaccine proved especially valuable for mass‑immunisation campaigns because it could be administered without needles. The oral vaccine even inspired a piece of popular culture. In the early 1960s, songwriter Jeffrey Sherman recounted that his father Robert and uncle Richard were working on music for the Disney film *Mary Poppins* when Jeffrey mentioned receiving the oral polio vaccine on a sugar cube at school. Robert Sherman asked, "Did it hurt?" Jeffrey replied, "I told him they put it on a sugar cube and you just ate it." The conversation sparked the creation of the song "A Spoonful of Sugar" (helps the medicine go down).

Both Dr Jonas Salk and Dr Albert Sabin refused to patent their discoveries. Dr Albert Sabin explained, "A lot of people insisted that I should patent the vaccine, but I didn't want to do that. It's my gift to all the world's children." Dr Jonas Salk echoed this sentiment, insisting that the vaccine remain freely available to everyone who needed it.

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