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The anniversary of the Salk team’s Polio vaccine is a source of hope for COVID-19

  • Innovation and Research

On April 12, 1955, the world learned the polio vaccine created by a University of Pittsburgh team led by Jonas Salk was effective in large-scale field tests. Humanity was given its first glimpse of the end of a pandemic that shuttered schools and caused more than 15,000 U.S. cases of paralysis per year, according to the Centers for Disease Control and Prevention.  

Sixty-five years later, lessons learned from the fight against polio are being applied to a new battle as researchers across the globe race to find a cure for COVID-19.

Since the vaccine created by Salk’s team was proven effective, researchers have moved the science forward based upon modern-day understanding of molecular biology and gene expression.

“Back in the 1950s there were two main approaches to the polio virus and vaccine problem—the killed-virus vaccine approach on one hand, and the live virus vaccine approach on the other,” explained Peter Salk, son of Jonas and a part-time professor of infectious diseases and microbiology in the Graduate School of Public Health.

In scientific terms, the team demonstrated that chemically inactivated polioviruses could be used successfully to create a vaccine. This gave researchers a broader set of tools to work with for creating vaccines against viral illnesses. And while the team’s virus was not the first killed-virus vaccine, it did smash conventional notions of how vaccines were supposed to be made.  Up to that point, scientific consensus was only weakened versions of live viruses could produce lasting protective immunity.

Peter said, “Today, the list of possibilities is so long. There’s been so much work done over these intervening decades to create a wide range of approaches to making vaccines and to be able to do so quickly. It’s just remarkable the way the world is poised now to respond to this new coronavirus pandemic.” 

Peter, who was 3 years old when his father moved the family from Michigan to Wexford, Pennsylvania, to work at Pitt, doesn’t remember much about the mood of the country during the outbreak, but one incident stands out in his mind.

“I remember on vacation in Lake Erie I wanted to go to an amusement park, but our parents didn’t want us to mix with crowds during polio season,” he said.   

Donald Burke, former dean of the Graduate School of Public Health, Distinguished University Professor of Health Science and Policy, Epidemiology and holder of the Jonas Salk Chair in Population Health, Epidemiology, remembers the chilling atmosphere all too well. He recalled being warned to stay away from a body of water in his neighborhood dubbed the “polio pond,” which was across the street from where a child struck with the illness lived. (Polio is transmitted through close person-to-person contact.)

Seven years after the Salk team’s polio vaccine was distributed, the incidence of polio in the U.S. had declined by 97% and the nation’s anxieties were eased. National priorities had also shifted in ways that would benefit public health and medical research for years to come.“Even though there wasn’t a full lockdown, people understood that polio was transmitted from contaminated areas,” he said. “More importantly, people were afraid. It was a different fear, it was a fear for the children.”

“There was very little government funding for any kind of biomedical research. The polio research was privately funded through the March of Dimes,” explained Randy Juhl, Dean Emeritus and Distinguished Service Professor Emeritus in the School of Pharmacy.

After the polio vaccine was proven effective, Juhl said the government recognized investment in science and medicine was a “lifesaving proposition.”

“The National Institutes of Health and all the federal funding of research that is done now received a huge jolt forward thanks to the polio vaccine.”

Within the University, investments in medicine and science blossomed, and its reputation in the fields became internationally known overnight. 

“The fact that the polio vaccine project was so successful made an enormous difference for the University in terms of its ability to expand its research programs and capacity,” Peter Salk said. “The University has such an extraordinary infrastructure in the health sciences, including the School of Medicine, the Graduate School of Public Health and the Center for Vaccine Research. It continues to make a wide range of important contributions in the fields of medicine and public health.”

Beyond Pitt, Juhl believes the story of the Salk team’s polio vaccine is one designed to advance American medical innovation as a whole. Juhl worked with Carl Kurlander, a senior lecturer in the Film and Media Studies Program in the Kenneth P. Dietrich School of Arts and Sciences, to create the documentary, “The Shot Felt Round the World,” which explores the creation of the vaccine and the important role that the Pittsburgh community played in its success.

“Whether Pitt ends up doing it again or not [with COVID-19], people should take a large degree of hope that when American medicine is unleashed on a problem, good things can really happen,” Juhl said.

Peter Salk’s call to medicine

When 9-year-old Peter Salk saw his father bring home a set of glass syringes and needles to inject the family, his first thought wasn’t about being delivered lifesaving immunity from a disease that had crippled tens of thousands. It was the anticipation of pain.

“I hated shots. But this time, for some reason, the needle must have missed a nerve because I didn’t even feel it,” he said. “I’ll never forget that moment, it was such a relief.”

It would be years before Peter fully understood that the momentary angst he and his brothers experienced in 1953 was part of an effort to alleviate years of agony that had been inflicted upon the country and the world by recurrent polio outbreaks. As use of the vaccine spread, the number of new cases of polio in this country dropped by 97% and his father was a full-fledged star.

And so was the rest of the family.

“As kids it was embarrassing having this much attention focused on the family. We had to get an answering service because of all of the calls from reporters. Imagine what that’s like for a kid in the sixth grade to have friends call their house and to have someone from an answering service pick up,” he said.

As a young adult, Peter respected and admired his father’s work but found himself attracted to his mother’s interests and talents in languages and music as well. For a while, he devoted attention to those fields, but the urge to be trained in medicine ultimately won out.

“Even though I had those other pulls, I felt internally I’d be doing a disservice to some ideal not to follow in the path my father had laid down. I really needed to pursue science to be able to hold my head high and feel I’d done something that would have a possibility of making a difference in that kind of way,” he said.

Following that path led to Peter working alongside his father in his Salk Institute lab, starting in 1972. Their collaboration began with cancer immunotherapy and would include multiple sclerosis studies and other vaccine related projects.

After the Salk lab closed in 1984, Jonas teamed up with the newly formed Immune Response Corporation in 1987 to work on an AIDS vaccine. Peter later joined him in the effort, under the auspices of a nonprofit foundation his father had formed. They worked together  on the AIDS vaccine project until 1995, when Jonas died of heart failure.

Today, as the world anticipates the breakthrough that will protect citizens from COVID-19, Peter thinks back to what was happening during his childhood: When the National Foundation for Infantile Paralysis, popularly known as the March of Dimes, funded research efforts to understand and prevent polio, including those of the Salk team. When schoolteachers and children alike mailed in dimes to support the organization’s efforts. When parents enthusiastically enrolled 1.8 million children to participate in a massive field trial of the vaccine. 

“The beauty of the polio vaccine experience is that everybody wanted it. It was a product of the need felt by millions of people in this country. There was no government funding. It was individuals throughout the country giving dime by dime, dollar by dollar, in movie theaters and from the doorsteps of their homes,” said Peter.

“It’s heartening to see the public support for the social measures being taken now to reduce the devastating spread of this newly emergent coronavirus. I anticipate that it will not be long before a variety of vaccines will begin to be tested with the goal of providing the kind of security we all want to feel in attempting to protect ourselves from this new worldwide threat.”

From the Pitt Med magazine archives

Among My Souvenirs”: Read about patients who participated in the polio vaccine clinical trials at Pitt.

It Works! It Works!”: News coverage of the 1955 success of the vaccine.

Pitt Medcast: Polio Pioneers”: Listen to firsthand accounts of how ordinary people helped win the struggle against one of the most crippling diseases in history.