How thousands of first- and second-graders saved the world from a deadly disease
Although Jonas Salk has gone down in history for helping rid the world (almost) of polio, his revolutionary vaccine wouldn't have been possible without the world’s largest clinical trial – and the bravery of thousands of kids.
Exactly 67 years ago, in 1955, a group of scientists and reporters gathered at the University of Michigan and waited with bated breath for Dr. Thomas Francis Jr., director of the school’s Poliomyelitis Vaccine Evaluation Center, to approach the podium. The group had gathered to hear the news that seemingly everyone in the country had been anticipating for the past two years – whether the vaccine for poliomyelitis, developed by Francis’s former student Jonas Salk, was effective in preventing the disease.
Polio, at that point, had become a household name. As the highly contagious virus swept through the United States, cities closed their schools, movie theaters, swimming pools, and even churches to stop the spread. For most, polio presented as a mild illness, and was usually completely asymptomatic – but for an unlucky few, the virus took hold of the central nervous system and caused permanent paralysis of muscles in the legs, arms, and even people’s diaphragms, rendering the person unable to walk and breathe. It wasn’t uncommon to hear reports of people – mostly children – who fell sick with a flu-like virus and then, just days later, were relegated to spend the rest of their lives in an iron lung.
For two years, researchers had been testing a vaccine that would hopefully be able to stop the spread of the virus and prevent the 45,000 infections each year that were keeping the nation in a chokehold. At the podium, Francis greeted the crowd and then proceeded to change the course of human history: The vaccine, he reported, was “safe, effective, and potent.” Widespread vaccination could begin in just a few weeks. The nightmare was over.
The road to success
Jonas Salk, a medical researcher and virologist who developed the vaccine with his own research team, would rightfully go down in history as the man who eradicated polio. (Today, wild poliovirus circulates in just two countries, Afghanistan and Pakistan – with only 140 cases reported in 2020.) But many people today forget that the widespread vaccination campaign that effectively ended wild polio across the globe would have never been possible without the human clinical trials that preceded it.
As with the COVID-19 vaccine, skepticism and misinformation around the polio vaccine abounded. But even more pervasive than the skepticism was fear. The consequences of polio had arguably never been more visible.
The road to human clinical trials – and the resulting vaccine – was a long one. In 1938, President Franklin Delano Roosevelt launched the National Foundation for Infantile Paralysis in order to raise funding for research and development of a polio vaccine. (Today, we know this organization as the March of Dimes.) A polio survivor himself, Roosevelt elevated awareness and prevention into the national spotlight, even more so than it had been previously. Raising funds for a safe and effective polio vaccine became a cornerstone of his presidency – and the funds raked in by his foundation went primarily to Salk to fund his research.
The Trials Begin
Salk’s vaccine, which included an inactivated (killed) polio virus, was promising – but now the researchers needed test subjects to make global vaccination a possibility. Because the aim of the vaccine was to prevent paralytic polio, researchers decided that they had to test the vaccine in the population that was most vulnerable to paralysis – young children. And, because the rate of paralysis was so low even among children, the team required many children to collect enough data. Francis, who led the trial to evaluate Salk’s vaccine, began the process of recruiting more than one million school-aged children between the ages of six and nine in 272 counties that had the highest incidence of the disease. The participants were nicknamed the “Polio Pioneers.”
Double-blind, placebo-based trials were considered the “gold standard” of epidemiological research back in Francis's day - and they remain the best approach we have today. These rigorous scientific studies are designed with two participant groups in mind. One group, called the test group, receives the experimental treatment (such as a vaccine); the other group, called the control, receives an inactive treatment known as a placebo. The researchers then compare the effects of the active treatment against the effects of the placebo, and every researcher is “blinded” as to which participants receive what treatment. That way, the results aren’t tainted by any possible biases.
But the study was controversial in that only some of the individual field trials at the county and state levels had a placebo group. Researchers described this as a “calculated risk,” meaning that while there were risks involved in giving the vaccine to a large number of children, the bigger risk was the potential paralysis or death that could come with being infected by polio. In all, just 200,000 children across the US received a placebo treatment, while an additional 725,000 children acted as observational controls – in other words, researchers monitored them for signs of infection, but did not give them any treatment.
As with the COVID-19 vaccine, skepticism and misinformation around the polio vaccine abounded. But even more pervasive than the skepticism was fear. President Roosevelt, who had made many public and televised appearances in a wheelchair, served as a perpetual reminder of the consequences of polio, as an infection at age 39 had rendered him permanently unable to walk. The consequences of polio had arguably never been more visible, and parents signed up their children in droves to participate in the study and offer them protection.
The Polio Pioneer Legacy
In a little less than a year, roughly half a million children received a dose of Salk’s polio vaccine. While plenty of children were hesitant to get the shot, many former participants still remember the fear surrounding the disease. One former participant, a Polio Pioneer named Debbie LaCrosse, writes of her experience: “There was no discussion, no listing of pros and cons. No amount of concern over possible side effects or other unknowns associated with a new vaccine could compare to the terrifying threat of polio.” For their participation, each kid received a certificate – and sometimes a pin – with the words “Polio Pioneer” emblazoned across the front.
When Francis announced the results of the trial on April 12, 1955, people did more than just breathe a sigh of relief – they openly celebrated, ringing church bells and flooding into the streets to embrace. Salk, who had become the face of the vaccine at that point, was instantly hailed as a national hero – and teachers around the country had their students to write him ‘thank you’ notes for his years of diligent work.
But while Salk went on to win national acclaim – even accepting the Presidential Medal of Freedom for his work on the polio vaccine in 1977 – his success was due in no small part to the children (and their parents) who took a risk in order to advance medical science. And that risk paid off: By the early 1960s, the yearly cases of polio in the United States had gone down to just 910. Where before the vaccine polio had caused around 15,000 cases of paralysis each year, only ten cases of paralysis were recorded in the entire country throughout the 1970s. And in 1979, the virus that once shuttered entire towns was declared officially eradicated in this country. Thanks to the efforts of these brave pioneers, the nation – along with the majority of the world – remains free of polio even today.
When Wayne Jonas was in medical school 40 years ago, doctors would write out a prescription for placebos, spelling it out backwards in capital letters, O-B-E-C-A-L-P. The pharmacist would fill the prescription with a sugar pill, recalls Jonas, now director of integrative health programs at the Samueli Foundation. It fulfilled the patient's desire for the doctor to do something when perhaps no drug could help, and the sugar pills did no harm.
Today, that deception is seen as unethical. But time and time again, studies have shown that placebos can have real benefits. Now, researchers are trying to untangle the mysteries of placebo effect in an effort to better treat patients.
The use of placebos took off in the post-WWII period, when randomized controlled clinical trials became the gold standard for medical research. One group in a study would be treated with a placebo, a supposedly inert pill or procedure that would not affect normal healing and recovery, while another group in the study would receive an "active" component, most commonly a pill under investigation. Presumably, the group receiving the active treatment would have a better response and the difference from the placebo group would represent the efficacy of the drug being tested. That was the basis for drug approval by the U.S. Food and Drug Administration.
"Placebo responses were marginalized," says Ted Kaptchuk, director of the Program in Placebo Studies & Therapeutic Encounters at Harvard Medical School. "Doctors were taught they have to overcome it when they were thinking about using an effective drug."
But that began to change around the turn of the 21st century. The National Institutes of Health held a series of meetings to set a research agenda and fund studies to answer some basic questions, led by Jonas who was in charge of the office of alternative medicine at the time. "People spontaneously get better all the time," says Kaptchuk. The crucial question was, is the placebo effect real? Is it more than just spontaneous healing?
Brain mechanisms
A turning point came in 2001 in a paper in Science that showed physical evidence of the placebo effect. It used positron emission tomography (PET) scans to measure release patterns of dopamine — a chemical messenger involved in how we feel pleasure — in the brains of patients with Parkinson's disease. Surprisingly, the placebo activated the same patterns that were activated by Parkinson's drugs, such as levodopa. It proved the placebo effect was real; now the search was on to better understand and control it.
A key part of the effect can be the beliefs, expectations, context, and "rituals" of the encounter between doctor and patient. Belief by the doctor and patient that the treatment would work, and the formalized practices of administering the treatment can all contribute to a positive outcome.
Conditioning can be another important component in generating a response, as Pavlov demonstrated more than a century ago in his experiments with dogs. They were trained with a bell prior to feeding such that they would begin to salivate in anticipation at the sound of a bell even with no food present.
Translating that to humans, studies with pain medications and sleeping aids showed that patients who had a positive response with a certain dose of those medications could have the same response if the doses was reduced and a dummy pill substituted, even to the point where there was no longer any active ingredient.
Researchers think placebo treatments can work particularly well in helping people deal with pain and psychological disorders.
Those types of studies troubled Kaptchuk because they often relied on deception; patients weren't told they were receiving a placebo, or at best there was a possibility that they might be randomized to receive a placebo. He believed the placebo effect could work even if patients were told upfront that they were going to receive a placebo. More than a dozen so call "open-label placebo" studies across numerous medical conditions, by Kaptchuk and others, have shown that you don't have to lie to patients for a placebo to work.
Jonas likes to tell the story of a patient who used methotrexate, a potent immunosuppressant, to control her rheumatoid arthritis. She was planning a long trip and didn't want to be bothered with the injections and monitoring required in using the drug, So she began to drink a powerful herbal extract of anise, a licorice flavor that she hated, prior to each injection. She reduced the amount of methotrexate over a period of months and finally stopped, but continued to drink the anise. That process had conditioned her body "to alter her immune function and her autoimmunity" as if she were taking the drug, much like Pavlov's dogs had been trained. She has not taken methotrexate for more than a year.
An intriguing paper published in May found that mild, non-invasive electric stimulation to the brain could not only boost the placebo effect on pain but also reduce the "nocebo" effect — when patients report a negative effect to a sham treatment. While the work is very preliminary, it may open the door to directly manipulating these responses.
Researchers think placebo treatments can work particularly well in helping people deal with pain and psychological disorders, areas where drugs often are of little help. Still, placebos aren't a cure and only a portion of patients experience a placebo effect.
Nocebo
If medicine were a soap opera, the nocebo would be the evil twin of the placebo. It's what happens when patients have adverse side effects because of the expectation that they will. It's commonly seem when patients claims to experience pain or gastric distress that can occur with a drug even when they've received a placebo. The side effects were either imagined or caused by something else.
"Up to 97% of reported pharmaceutical side effects are not caused by the drug itself but rather by nocebo effects and symptom misattribution," according to one 2019 paper.
One way to reduce a nocebo response is to simply not tell patients that specific side effects might occur. An example is a liver biopsy, in which a large-gauge needle is used to extract a tissue sample for examination. Those told ahead of time that they might experience some pain were more likely to report pain and greater pain than those who weren't offered this information.
Interestingly, a nocebo response plays out in the hippocampus, a part of the brain that is never activated in a placebo response. "I think what we are dealing with with nocebo is anxiety," says Kaptchuk, but he acknowledges that others disagree.
Distraction may be another way to minimize the nocebo effect. Pediatricians are using virtual reality (VR) to engage children and distract them during routine procedures such as blood draws and changing wound dressings, and burn patients of all ages have found relief with specially created VRs.
Treatment response
Jonas argues that what we commonly call the placebo effect is misnamed and leading us astray. "The fact is people heal and that inherent healing capacity is both powerful and influenced by mental, social, and contextual factors that are embedded in every medical encounter since the idea of treatment began," he wrote in a 2019 article in the journal Frontiers in Psychiatry. "Our understanding of healing and ability to enhance it will be accelerated if we stop using the term 'placebo response' and call it what it is—the meaning response, and its special application in medicine called the healing response."
He cites evidence that "only 15% to 20% of the healing of an individual or a population comes from health care. The rest—nearly 80%—comes from other factors rarely addressed in the health care system: behavioral and lifestyle choices that people make in their daily life."
To better align treatments and maximize their effectiveness, Jonas has created HOPE (Healing Oriented Practices & Environments) Note, "a patient-guided process designed to identify the patient's values and goals in their life and for healing." Essentially, it seeks to make clear to both doctor and patient what the patient's goals are in seeking treatment. In an extreme example of terminal cancer, some patients may choose to extend life despite the often brutal treatments, while others might prefer to optimize quality of life in the remaining time that they have. It builds on practices already taught in medical schools. Jonas believes doctors and patients can use tools like these to maximize the treatment response and achieve better outcomes.
Much of the medical profession has been resistant to these approaches. Part of that is simply tradition and limited data on their effectiveness, but another very real factor is the billing process for how they are reimbursed. Jonas says a new medical billing code added this year gives doctors another way to be compensated for the extra time and effort that a more holistic approach to medicine may initially require. Other moves away from fee-for-service payments to bundling and payment for outcomes, and the integrated care provided by the Veterans Affairs, Kaiser Permanente and other groups offer longer term hope for the future of approaches that might enhance the healing response.
The Women of RNA: Two Award-Winners Share Why They Spent Their Careers Studying DNA's Lesser-Known Cousin
When Lynne Maquat, who leads the Center for RNA Biology at the University of Rochester, became interested in the ribonucleic acid molecule in the 1970s, she was definitely in the minority. The same was true for Joan Steitz, now professor of molecular biophysics and biochemistry at Yale University, who began to study RNA a decade earlier in the 1960s.
"My first RNA experiment was a failure, because we didn't understand how things worked," Steitz recalls. In her first undergraduate experiment, she unwittingly used a lab preparation that destroyed the RNA. "Unknowingly, our preparation contained enzymes that degraded our RNA."
At the time, scientists pursuing genetic research tended to focus on DNA, or deoxyribonucleic acid — and for good reason. It was clear that the enigmatic double-helix ribbon held the answers to organisms' heredity, genetic traits, development, growth and aging. If scientists could decipher the secrets of DNA and understand how its genetic instructions translate into the body's functions in health and disease, they could develop treatments for all kinds of diseases. On the contrary, the prevailing dogma of the time viewed RNA as merely a helper that passively carried out DNA's genetic instructions for protein-making — so it received much less attention.
But Maquat and Steitz weren't interested in heredity. They studied biochemistry and biophysics, so they wanted to understand how RNA functioned on the molecular level — how it carried instructions, catalyzed reactions, and helped build protein bonds, among other things.
"I'm a mechanistic biochemist, so I like to know how things happen," Maquat says. "Once you understand the mechanism, you can think of how to solve problems." And so the quest to understand how RNA does its job became the focus of both women's careers.
"People can now appreciate why some of us studied RNA for such a long time."
Half a century later, in 2021, their RNA work has earned two prestigious recognitions only months from each other. In February, they received the Wolf Prize in Medicine, followed by the Warren Alpert Foundation Prize in May, awarded to scientists whose achievements led to prevention, cure or treatments of human diseases.
It was the development of the COVID-19 vaccines that made RNA a household name. Made by Moderna and Pfizer, the vaccines use the RNA molecule to deliver genetic instructions for making SARS-CoV-2's characteristic spike protein in our cells. The presence of this foreign-looking protein triggers the immune system to attack and remember the pathogen. As the vaccines reached the finish line, RNA took center stage, and it was Maquat's and Steitz's research that helped reveal how these molecular cogwheels drive many biological functions within cells.
If you think of a cell as a kingdom, the DNA plays the role of a queen. Like a monarch in a palace, DNA nestles inside the cell's nucleus issuing instructions needed for the cell to function. But no queen can successfully govern without her court, her messengers, and her soldiers, as well as other players that make her kingdom work. That's what RNAs do — they act as the DNA's vassals. They carry instructions for protein assembly, catalyze reactions and supervise many other processes to make sure the cellular kingdom performs as it should.
There are a myriad of these RNA vassals in our cells, and each type has its own specific task. There are messenger RNAs that deliver genetic instructions for protein synthesis from DNA to ribosomes, the cells' protein-making factories. There are ribosomal RNAs that help stitch together amino acids to make proteins. There are transfer RNAs that can bring amino acids to this protein synthesis machine, keeping it going. Then there are circular RNAs that act as sponges, absorbing proteins to help regulate the activity of genes. And that's only the tip of the iceberg when it comes to RNA diversity, researchers say.
"We know what the most abundant and important RNAs are doing," says Steitz. "But there are thousands of different ones, and we still don't have a full knowledge of them."
Critical to RNA's proper functioning is a process called splicing, in which a precursor mRNA is transformed into mature, fully-functional mRNA — a phenomenon that Steitz's work helped elucidate. The splicing process, which takes place in cellular assembly lines, involves removing extra RNA sequences and stringing the remaining RNA pieces together. Steitz found that tiny RNA particles called snRNPs are crucial to this process. They act as handy helpers, finding and removing errant genetic material from the mRNA molecules.
A dysfunctional RNA assembly line leads to diseases, including many cancers. For instance, Steitz found that people with Lupus — an autoimmune disorder — have antibodies that mistakenly attack the little snRNP helpers. She also discovered that when snRNPs don't do their job properly, they can cause what scientists call mis-splicing, producing defective mRNAs.
Fortunately, cells have a built-in quality-control process that can spot and correct these mistakes, which is what Maquat studied in her work. In 1981, she discovered a molecular quality-control system that spots and destroys such incorrectly assembled mRNA. With the cryptic name "nonsense-mediated mRNA decay" or NMD, this process is vital to the health and wellbeing of a cellular kingdom in humans — because splicing mistakes happen far more often than one would imagine.
"We estimate that about a third of our mRNA are mistakes," Maquat says. "And nonsense-mediated mRNA decay cleans up these mistakes." When this quality-control system malfunctions, defective mRNA forge faulty proteins, which mess up the cellular machinery and cause disease, including various forms of cancer.
Scientists' newfound appreciation of RNA opens door to many novel treatments.
Now that the first RNA-based shots were approved, the same principle can be used for create vaccines for other diseases, the two RNA researchers say. Moreover, the molecule has an even greater potential — it can serve as a therapeutic target for other disorders. For example, Spinraza, a groundbreaking drug approved in 2016 for spinal muscular atrophy, uses small snippets of synthetic genetic material that bind to the RNA, helping fix splicing errors. "People can now appreciate why some of us studied RNA for such a long time," says Maquat.
Steitz is thrilled that the entire field of RNA research is enjoying the limelight. "I'm delighted because the prize is more of a recognition of the field than just our work," she says. "This is a more general acknowledgment of how basic research can have a remarkable impact on human health."
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.