To many Americans, the cold war is ancient history. Yet only a few decades ago the planet was dangerously divided between West and East, and the antagonism between the U.S. and the Soviet Union defined global politics. Flare-ups such as the Korean “police action,” which killed millions of people in the early 1950s, and the Cuban missile crisis, 10 years later, drew the American and Soviet governments and their proxies to the threshold of nuclear war.

At the same time, Americans lived in mortal fear of an enemy much closer to home. That enemy was polio—short for poliomyelitis, also known as infantile paralysis because of its prevalence among children and young adults. Scientists had known its cause—a virus spread via contact with fecal matter—since the 1930s, but its control eluded them. During sporadic epidemics authorities closed swimming pools, movie houses and other popular gathering spots, hoping to contain the disease, which attacked the central nervous system, often crippling and sometimes killing its victims. Newsreel footage of toddlers with twisted limbs and teenagers lying helplessly on their backs in coffinlike iron lungs frightened the public as few of the era’s images did.

Then, during the deep winter of the cold war, two extraordinary scientists—one an American, the other a Russian—formed a powerful alliance. Their joint venture would have outraged fanatics on both sides of the iron curtain if those fanatics had been aware of it. Yet the collaboration—fleshed out in archival materials recently made available at the University of Cincinnati and by several contemporaneous sources—led to one of the greatest medical achievements of the 20th century and saved countless lives around the world.

The Quest for an Effective Vaccine
By the early 1950s the quest for a polio vaccine had moved into high gear in the U.S. Virologists Jonas E. Salk of the University of Pittsburgh and Albert B. Sabin of the University of Cincinnati had emerged as the most prominent among dozens of American researchers funded by the National Foundation for Infantile Paralysis (now the March of Dimes Foundation). In 1955, after tests involving nearly two million schoolchildren across the country, Salk’s vaccine became the first to receive the approval of the U.S. government. While Salk became, in the words of historian David M. Oshinsky, “an instant hero, a celebrity-scientist,” Sabin continued to labor over what he believed was a superior vaccine.

Both approaches would protect against infection, though in different ways. The Salk vaccine was made up of polioviruses that had been inactivated, or “killed” in popular terminology, using the chemical formalin. Sabin thought that a vaccine made up of a weakened but still active poliovirus would be more effective than a killed-virus vaccine because it could generate lifelong immunity. Live-virus vaccines also offered the possibility of secondary immunization, in which vaccinated children would passively infect their contacts with the vaccine virus, thereby immunizing many unvaccinated people. Finally, unlike Salk’s vaccine, which was injected, the Sabin vaccine could be administered in a bite-size sugar cube or swallowed off a spoon. Thus, tens of thousands, even millions, of citizens could be given the vaccine quickly, inexpensively, and without the fear and fuss of needles. For all these reasons, Sabin believed that the best hope of not only controlling the disease but wiping it off the face of the earth lay with his live-virus oral vaccine.

Mainstream media made much of the competition between Sabin and Salk even though other important scientists were also involved in the “race” to capture the U.S. market. There was a certain amount of truth underlying the press’s exaggerations. Salk and Sabin—despite their common Russian-Jewish heritage, funding source and virological enemy—disliked each other intensely. Sabin scoffed at Salk’s “kitchen chemistry,” insisting that Salk “didn’t discover anything.” Salk believed that Sabin, jealous of his early success, was “out for me from the very beginning.” Sabin doubtless resented the enormous acclaim Salk enjoyed following the dead-virus vaccine’s approval, whereas Salk surely bristled at the suggestion that, in the words of one contemporary, he “was an overblown publicist, while Sabin was the real scientist.”

By 1955 Sabin had identified the three strains of poliovirus he believed had to be included to make his vaccine effective (Salk had used different strains), but he lacked the numbers to prove himself correct. Beginning in the mid-1950s, Sabin tested his vaccine on hundreds of volunteers, including young adults incarcerated at the federal prison in Chillicothe, Ohio, as well as himself, his wife and their two daughters, neighbors and friends. (He assured the prison volunteers that they faced considerably less risk ingesting his vaccine than he had faced driving from Cincinnati in a snowstorm.) Even as he conducted the tests, though, he knew that hundreds, even thousands, of study participants would not be enough. He needed millions of subjects to document his vaccine’s safety and efficacy. Because the Salk vaccine was already widely used in the U.S., there were not enough unvaccinated Americans to provide sufficient numbers.

Meanwhile, in the Soviet Union, the incidence of polio was rising sharply. For years during the dictatorship of Joseph Stalin, authorities denied that polio was a problem in the “workers’ paradise.” But as outbreaks in Moscow, Minsk and population centers as far away as Siberia put the lie to the propaganda, Soviet scientists sought the same answers pursued by their U.S. counterparts. Soviet and American investigators had occasionally joined forces in the quarter of a century between the 1917 Bolshevik revolution and the end of World War II. That cooperation all but vanished, however, when East and West squared off in the aftermath of the Allied victory in 1945. Then, in 1953, Stalin died, and his slightly less rigid successors, alarmed by the increasing polio numbers, directed their researchers to look beyond their borders for help.

Russia’s two most prominent virologists at the time were Anatoli Smorodintsev and Mikhail P. Chumakov. In January 1956 Smorodintsev, Chumakov and Chumakov’s wife, Marina Voroshilova—a distinguished researcher in her own right—traveled to the U.S. to confer with several American scientists, including Salk and Sabin. Though quietly approved by both governments, the visit was shadowed by cold war bugbears: the Russians were required, for instance, to cross the country by rail rather than, more conveniently, by air, and the Americans were convinced that at least one “doctor” accompanying the visitors was a KGB operative. Still, both sides discreetly hailed the tour as a success. Valuable scientific information was exchanged; more important, as events transpired, Chumakov and Sabin hit it off, establishing the ties that would lead to a spectacularly productive relationship.

Dr. Sabin Goes to Russia
In June 1956, authorized by a cautiously obliging U.S. Department of State and vetted by the ever watchful FBI, Sabin flew to Russia and, over the next several weeks, met with Chumakov, Voroshilova, Smorodintsev and other key researchers.

Even though both he and Salk had been invited, Sabin was on a mission of one. Decades later Salk’s son Peter told Oshinsky that his father had turned down the Russians’ invitation because Salk’s wife, weary of her husband’s frequent absences, had finally “put her foot down.” Oshinsky’s chronicle suggests another possibility. As a younger man, Salk had been one of thousands of Americans who publicly espoused left-wing causes and thus aroused the FBI’s attention. Perhaps Salk feared that a visit to the Soviet Union would be misconstrued. More likely, the “celebrity-scientist,” whose game-changing vaccine had made him famous and wealthy, believed he had little to gain from a Soviet trip. Unlike Sabin, he had nothing to prove.

Sabin, for his part, was returning to his roots. He was born in 1906 in Bialystok, a Polish city that had been part of imperial Russia and then the Soviet Union. His family was poor. His father, a weaver, was the breadwinner, but his mother, he recalled much later, was “the one with the initiative.” After the Sabins emigrated to the U.S. in 1921, Albert quickly mastered the English language and American ways. After earning a medical degree from New York University in 1931, he made a name for himself as a medical researcher in New York City, London and, eventually, Cincinnati, focusing on polio, encephalitis and other neurological diseases. He was among the researchers who challenged the received wisdom regarding the way by which the poliovirus entered the human body. The virus’s entryway was not the nasal passages, as Simon Flexner, the “father of polio research,” had theorized, but the alimentary canal; after it entered through the mouth, the virus migrated to the digestive tract, where it infiltrated the bloodstream en route to the central nervous system. That knowledge would prove critical to the next step—developing a vaccine that could induce the immune system to attack the virus in the blood.

In the U.S.S.R., Sabin faced a number of new challenges as he huddled with researchers and championed his live-virus vaccine. His exposure to the language as a child notwithstanding, he was never proficient in Russian, nor were most of his Soviet counterparts fluent in English. Interpreters were provided, but the painstaking collaboration surely would have been easier if the scientists had communicated in the same language. It is tempting to wonder, moreover, what fears and biases might have lingered from Sabin’s childhood in Bialystok, where Jews lived in constant fear of attack and where, he once remarked, he grew up “thinking of Russian soldiers as murderers.” If Sabin harbored such thoughts during his Soviet visits, he apparently kept them to himself. Later, he would insist he was unfazed by the Soviet and American agents who tracked his movements and recorded his public comments.

Despite the complications, Sabin developed valuable working—and, in some cases, close personal—relationships with his Russian hosts over the next several years. None proved to be more beneficial than his friendship with Chumakov.

“The General” and the Red Phone
Chumakov, it turned out, was a perfect match for Sabin. He was born in 1909 to a humble family in the Caucasus. His father was an army veterinarian, his mother a peasant who did not learn to read or write until she was in her 70s. When Chumakov was 16, his son Konstantin says, he went off to Moscow to attend college and was later admitted to both law and medical schools before choosing a career in medicine.

Neither Chumakov nor Sabin suffered fools gladly, and both were convinced that fools were everywhere. Sabin’s brilliance as a scientist was rivaled only by his fearsome reputation as a taskmaster and competitor. Fastidious himself, he demanded a fana­tical attention to detail from his staff; dead sure of his positions, he publicly challenged his rivals’ conclusions. Philip Russell, an eminent virologist and a founder of the Washington, D.C.–based Sabin Vaccine Institute, knew Sabin and many of the investigators who worked in Sabin’s labs. Echoing the widespread opinion of both the man and the researcher, Russell says, “Albert was driven and meticulous—a visionary scientist. He was also tough, arrogant and never wrong—even when he was.” Sabin’s acquaintances might have been surprised to learn that Chumakov may have had the more volcanic personality. In a 1958 letter to Sabin, Chumakov complained about “the intrigues of ... cowards and pseudo­­specialists,” whom he did not hesitate to cite by name.

“Thankfully, they found each other,” says Konstantin, who has lived in the U.S. since 1989 and is currently an associate director in the Office of Vaccines Research and Review at the Food and Drug Administration. “Sabin had the vaccine that could save uncounted numbers from death or paralysis, and my father found the way to push it past the bureaucratic obstacles. Sabin called my father ‘the General’ because he could get things done.”

Russian virologists had experimented with Salk’s dead-virus vaccine, but Chumakov sought a simpler, less costly, more efficacious way to extend protection against polio across the vast population of the Soviet Union. In 1959 Chumakov decided to organize the first large-scale clinical trials of the oral vaccine made from the live, weakened strains Sabin had developed in the U.S. It would be a monumental undertaking, fraught with problems—beginning with approval from the top.

“Sabin publicly gave credit to my father and the Soviet system whose organization made such large trials possible,” Konstantin says. “But I’m not sure my father ever told Sabin the true story behind it. What actually happened—according to my father—went like this:

“My father couldn’t get permission for a really big clinical trial. A lot of people in the Health Ministry were opposed to it. He was told, basically, ‘We have the Salk vaccine, and it works fine, so there’s no reason for you to test the live virus.’ Well, my father decided to go around them.

“In the Soviet Union there was a higher authority—the Politburo [then known as the Presidium of the Central Committee], which consisted of a small group of Communist Party officials who could overrule everybody. At the time, Anastas Mikoyan was the Politburo member responsible for public health. Mikoyan was not a medical man—he was a political figure who went back to the revolution. But he and my father were well acquainted. Mikoyan may have appointed him to head the polio initiative in the first place.” Refusing to accept the ministry’s decision not to grant permission for the oral vaccine tests, Chumakov picked up one of the red telephones provided for the exclusive use of the most powerful people in the Kremlin—he was not among them—and dialed Mikoyan’s number.

As Chumakov related the story to his son, he got right to the point and asked Mikoyan’s approval to proceed with the live-virus vaccine tests.

“Are you sure this is a good vaccine, Mikhail?” Mikoyan asked. “And that it’s safe?”

“Yes,” the virologist replied. “I’m absolutely sure.”

“Then go ahead,” Mikoyan said.

“That was it,” says the younger Chumakov, whose account rings true with others familiar with the principals. “The only per­mission he had was verbal, over that Politburo hotline. Of course, the health minister was unhappy, but there was nothing he could do.”

A Lasting Success
In 1959 Chumakov tested the oral vaccine on 10 million children throughout the U.S.S.R. The Soviets set up vaccination centers not only at hospitals and clinics but in schools, nurseries and other nonmedical locations. Within the next several months virtually everybody under the age of 20—eventually including almost 100 million persons in the Soviet Union and its satellites—received the vaccine, either by medicine dropper or inside a piece of candy, and the outcome seemed to justify the effort. Chumakov was ecstatic about the vaccine’s widespread application, and within a year a representative of the World Health Organization (WHO) acknowledged both the vaccine’s safety and a significant reduction of paralytic cases.

There were still, to be sure, Western scientists who refused to accept the glowing reports from the other side of the iron curtain. “The general reaction, usually not expressed publicly, was, ‘Well, you can’t trust anything those people do,’” Sabin grumbled more than once. But the documented achievement of the Sabin-Chumakov collaboration ultimately trumped the ideological differences. Their oral live-virus vaccine became the weapon of choice against polio around the world—including, after its full federal licensing in 1962, for three decades in the U.S. In 1972 Sabin donated his poliovirus strains to the WHO, with the objective of making the vaccine accessible in even the poorest countries.

Today polio remains a serious threat only in parts of Pakistan, Afghanistan and Nigeria. If polio is ever completely eradicated from the globe—as seems more and more possible—the world will have the little-known and improbable collaboration between Albert Sabin and Mikhail Chumakov to thank for it.

This article was published in print as "Birth of a Cold War Vaccine."