The mass inoculation of millions of American children against polio in 1955, like the vaccinations of millions of American adults against COVID-19 in 2021, was a triumph of science.

But the polio vaccine had overwhelming public acceptance, while stubborn pockets of vaccine hesitancy persist across the U.S. for the COVID-19 vaccine. Why the difference? One reason, historians say, is that in 1955, many Americans had an especially deep respect for science.

"If you had to pick a moment as the high point of respect for scientific discovery, it would have been then," says David M. Oshinsky, a medical historian at New York University and the author of Polio: An American Story. "After World War II, you had antibiotics rolling off the production line for the first time. People believed infectious disease was [being] conquered. And then this amazing vaccine is announced. People couldn't get it fast enough."

Today, the unprecedented speed of the COVID-19 vaccines' development, along with a flood of disinformation on the internet about all vaccines, has led to a lingering hesitancy among some Americans to receive the increasingly available COVID-19 shots.

"In hindsight, Operation Warp Speed wasn't the best name," says Oshinsky. "It sounds like the project prioritized speed over everything else. They did roll it out quickly, but the FDA and CDC have done an amazing job of testing the vaccines and ensuring their safety and efficacy."

During the late 1940s and early '50s, according to statistics from the Centers for Disease Control and Prevention, polio disabled an average of 35,000 people a year in the U.S., most of them children. As outbreaks popped up across the country in the hot summer months, people were terrified and voluntarily isolated. Many parents kept their children close to home and away from community gathering spots like movie theaters, roller rinks and beaches.

"Back then, it affected business and travel," says Stacey D. Stewart, current president and CEO of the March of Dimes. "People didn't know how the virus was transmitted. They lived in a state of fear. Pools were closed. Businesses were affected because people didn't want to be out in public."

President Franklin D. Roosevelt, who had himself essentially lost the use of his legs after a polio infection in 1921, when he was 39, launched the National Foundation for Infantile Paralysis, a charitable organization, in the late 1930s. Later renamed the March of Dimes, the foundation took the lead in efforts to fund research at a time when the National Institutes of Health was in its infancy.

"Roosevelt's passion for finding a solution — a cure, a vaccine — made polio a priority coming from the very top leader of this country," says Stewart. "People across the country felt like they were called to duty. It was a call to action, like the war effort."

An army of volunteers for the March of Dimes, largely mothers, went door to door, distributing the latest information about polio and the effort to stop it; they also asked for donations. As little as a dime would help, they said. And the dimes and dollars poured in, Oshinsky says, handed to the volunteers, or inserted into cardboard displays at store checkout counters or placed in envelopes sent directly to the White House.

Cases of polio may have peaked in the U.S. in 1952 with nearly 60,000 children infected. More than 3,000 died. (By comparison, roughly a year's worth of comparable statistics for the COVID-19 pandemic reveal more than 32 million reported cases in the U.S. so far and more than 573,000 deaths.)

The years-long campaign of information and donations to the polio eradication effort made anxious Americans feel they were invested in a solution, Stewart says. So confident was the public in the research leading up to the polio vaccine that by the time the Salk vaccine was ready for experimental testing in 1954, the parents of 600,000 children volunteered their own offspring as research subjects.

When the results of those studies showed the vaccine to be safe and effective in 1955, church bells rang. Loudspeakers in stores, offices and factories blared the news. People crowded around radios. "There was jubilation," says Stewart. People couldn't wait to sign their kids up for a shot.

Then tragedy struck. One of the six labs manufacturing the vaccine, Cutter Laboratories in Berkeley, Calif., made a terrible mistake. The correct list of ingredients for the Salk vaccine called for polio virus that had been inactivated, but in the Cutter facility, the process of killing the virus proved defective. As a result, batches of the company's vaccine went out that mistakenly contained active polio virus. Of the 200,000 children who received the defective vaccine, 40,000 got polio from it; 200 were left with varying degrees of paralysis, and 10 died.

In April, the U.S. campaign against COVID-19 suffered a blow too. Reports that an extremely rare but serious blood-clotting disorder might have resulted from Johnson & Johnson's vaccine — one of the three authorized for use against COVID-19 in the U.S. — once again raised the question of whether possible harms caused by a vaccine might derail people's confidence in a public health campaign at a crucial time.

On April 13, the CDC and the Food and Drug Administration jointly announced that among the 6.8 million doses of the Johnson & Johnson vaccine administered to date, six cases of a serious blood-clotting issue had been recorded, and one had woman died.

Ten days later, after a careful review of those cases and others, the pause was lifted and immunization with the vaccine resumed, with new guidance for recipients and doctors about what to look for in the way of symptoms and how to treat these extremely rare events.

Polio vaccinations were temporarily halted in 1955 following the Cutter error as well. In both incidents, health officials followed the science. After Cutter's manufacturing error was pinpointed as the problem, vaccinations restarted within weeks, with renewed quality control efforts and minus any involvement from Cutter Laboratories.

In 1955, mothers and fathers jumped right back in following the Cutter tragedy, once again signing permission slips and lining their kids up to get their polio shot. It was widely understood and accepted that the risks of polio were a much greater threat than the risks of the vaccine.

"I think back then, people were so personally invested in the vaccine," Stewart says. "They listened to what happened in the Cutter case, and they understood. They continued to trust."

Because of that trust, the campaign to prevent polio with vaccines — first Jonas Salk's and then also Albert Sabin's — was successful, eventually nearly eliminating the disease from the planet. But that also means, says Oshinsky, that people born after the mass vaccination effort don't have memories of how bad the disease could be.

"Vaccines have been a job ... done so well they have obliterated evidence of what the disease can cause: kids on crutches, in wheelchairs, in iron lungs," Oshinsky says. "I remember seeing the occasional empty desk in school because a child had died. People had seen polio every summer, and they wanted kids vaccinated as soon as possible."

The polio vaccine effort offers some lessons for today, says Stewart. First, volunteers from local communities are trusted and invaluable in providing education on disease, research and vaccines. To get people's attention, add to that numerous high-profile advocates — individuals recognized and esteemed by various parts of the population. The March of Dimes recruited Judy Garland, Mickey Rooney and Marilyn Monroe to join the fundraising effort to educate people about polio and the value of the vaccine. And in 1956, Elvis Presley was vaccinated backstage at The Ed Sullivan Show.

Vaccine efforts at the time did have to contend with racism. Oshinsky writes, for example, about some areas in the Jim Crow South where Black children lined up for shots on the front lawns of white schools, while white children got their shots indoors. The Black children, he notes, weren't allowed inside those white schools, even to use the bathrooms. Very aware of the prejudices of the times, Stewart says, the March of Dimes knew it would also need to recruit prominent and popular Black performers to promote the polio vaccine.

Sammy Davis Jr., Louis Armstrong and Ella Fitzgerald joined the campaign. "There was a very early recognition that you couldn't just have white people talking about the vaccine," Stewart says. In addition to beloved Black celebrities, she says, "the March of Dimes had Black children on the posters to raise awareness in Black communities."

It has now been several months since Sandra Lindsay, a nurse on Long Island, N.Y., became the first person in the U.S. to receive a COVID-19 vaccination. At least 30% of the country's total residents are now fully vaccinated, and more than 44% have received at least one dose.

"That's the low-hanging fruit," says Oshinsky. "After you vaccinate all the people champing at the bit to get it, that's when you have to think of strong marketing strategies for those who are hesitant."

The strong, consistent message during the polio years was "We're all in this together." The same message, says Stewart, must come across loud and clear today.

Susan Brink is a freelance writer who covers health and medicine. She is the author of The Fourth Trimester and co-author of Change of Heart.

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