The Myth of Jonas Salk
It was Albert Sabin’s vaccine, not Salk’s, that truly defeated polio.
Medical Mythmaking Splendid Solution:
Jonas Salk and the Conquest of Polio
By Jeffrey Kluger
Putnam, 2004, $25.95 Polio: An American Story
By David M. Oshinsky
Oxford University Press, 2005, $30.00 April 12 was the day, 50 years ago, that the U.S. Public Health Service licensed the killed-virus vaccine against poliomyelitis developed by Jonas Salk. In the decades since, a great myth has grown to dominate the popular imagination. Its name is “The Conquest of Polio,” and Salk is its hero.
On the anniversary day and minute, the Smithsonian Institution tolled the bell on its oldest building 50 times to open an exhibit at the National Museum of American History centered on Salk and the vaccine. That morning, the science correspondent for National Public Radio extolled the polio conquest and the Salk vaccine in the first part of a three-part series. Publications marked the occasion – the New York Times, the Washington Post, the Chicago Tribune, the Los Angeles Times, USA Today, Smithsonian magazine, and a dozen others. In the weeks before, two new books had appeared. Six more are now in the works.
This retelling of the history of polio, however, is largely a distortion. The full, true story is far more complex. Its hero is Albert Sabin – for if any one man conquered polio, it was Sabin, who developed the oral attenuated live-virus vaccine. While Salk’s vaccine did slow down the incidence of polio among middle-class Americans, its cost and its requirement of three injections and a booster meant that for years the disease continued to affect the poor and others lacking access to proper medical care. It was only after Sabin’s oral vaccine, which was cheap, effective, and easy to administer, was licensed for production in 1962 that polio could be fully controlled in the United States.
But it seems some prefer the myth to the fact. Jeffrey Kluger’s Splendid Solution: Jonas Salk and the Conquest of Polio pushes the myth to an extreme. Kluger is a senior writer at Time. In his version, the myth contains three assertions. First, Salk was a great scientist “with such a deep regard for scientific facts,” Kluger writes, “a tectonic force in scientific history.” Second, the Salk vaccine was effective and conquered polio in this country. If only it had been used for a few more years, it would have eradicated the disease. Third, the “temperamental” Albert Sabin, who was working on his own vaccine at the University of Cincinnati, sabotaged the killed-virus vaccine. Kluger implies that Sabin’s opposition had no basis in science but arose from jealousy.
In contrast, contends Kluger, Salk was controlled in his demeanor: “Stupidity always made him angry; malevolent stupidity made him angrier still. He wouldn’t show it; he never did. You couldn’t run the kind of lab he ran and conduct the kind of research he conducted and allow yourself the luxury of pique.” Kluger’s reconstruction of the history, and especially of the controversy between Salk and Sabin, depends heavily, painfully, on innuendo and inference.
These charges demand careful attention. In the first place, Salk’s research was altogether derivative. It arose from four crucial discoveries. In 1949, David Bodian, Isabel Mountain Morgan, and Howard Howe at the Poliomyelitis Laboratory at Johns Hopkins University first established that polio comes not in a single variety but in at least three. Then they showed that a preparation of killed virus could inoculate monkeys against the disease. In 1952, Dorothy Horstmann of Yale University School of Medicine and Bodian, independently, established that polio is a blood-borne disease. Also in 1952, Howe suggested that killed virus could produce good antibody responses in children.
D. A. Henderson – the man who organized the worldwide eradication of smallpox – was then at the U.S. Communicable Disease Center (now the Centers for Disease Control and Prevention) in Atlanta. In a recent interview, he told me, “So Jonas came in at this point with pretty much everything done except for moving on to wider-scale human trials.”
But by the early 1950s, Sabin and many other immunologists and epidemiologists were convinced that an oral attenuated live-virus vaccine would be more effective. Soon after Salk’s vaccine became available in the spring of 1955, many recognized that it had serious problems.
For Sabin, the problems were three: safety, efficacy, and practicality. Early on, Sabin held that one particular strain Salk had used–a highly virulent strain called Mahoney – would be hard to kill and thus dangerous. The question of efficacy was whether any killed-virus vaccine could produce lifelong immunity. And finally, even though the vaccine did stimulate production of antibodies, three shots were necessary, plus a later booster. Sabin put the point most succinctly: “The need for inoculating large amounts and the need for repetition are bad.” In contrast, an oral vaccine with a small dose of the attenuated versions of each of the three strains, administered once, would give lifelong immunity.
Then came the shock of the Cutter incident. On April 24, 1955, just days after the Salk vaccine went into use, polio broke out among children who had received shots from a batch made by Cutter Laboratories in California. Eleven died. It is usually asserted that the Cutter incident was caused by particular lots of vaccine that still contained live polio virus, but the presence of the live virus has never been satisfactorily explained. Joshua Lederberg, who received a Nobel Prize in 1958 for his work in bacterial genetics, was involved in polio-virus research in the early 1950s. Lederberg told me in March 2002 that the Cutter incident is “still a little bit of a mystery.” The virus strains in the Salk vaccine were inactivated with formaldehyde. Lederberg said that the chemistry of the formaldehyde-virus interaction has never been adequately studied. “It is my opinion that under some conditions, it is a reversible reaction,” he said. “In fact I know that it is.” He went on, “The question is [with] what reagents or under what conditions a formaldehyde will come off the inactivated complex and thus restore its infectivity.” And so, Lederberg said, because nobody understood the reasons for the “Cutter catastrophe,” research continued into alternatives to the Salk vaccine. (After the Cutter incident, production methods were changed. No further safety problems with the vaccine have been reported.)
The force behind Salk and his vaccine was the National Foundation for Infantile Paralysis – later rechristened the March of Dimes – and in particular its president, Basil O’Connor, who was not a scientist. In an interview in 1984, Salk said, “I would say that the fact that the vaccine became available in 1955 was attributable to the existence of Basil O’Connor, that without him the story would have been quite different….He had it within his power to cause almost anything to happen.” As Sabin dug deeper into his vaccine research, he began openly to oppose the foundation, for he believed it ignored important scientific conclusions and was unrealistically pushing for a quick solution.
Sabin was particularly critical of O’Connor, charging that he was biased. In a letter dated June 25, 1955, he asked O’Connor, “Would it not be better if you as President of the National Foundation of Infantile Paralysis observed a more impartial attitude regarding the scientific work and contributions of all scientists whose work is supported by the donations from the American people through the Foundation which you so ably lead?” On August 1, in another letter, Sabin attacked O’Connor’s interpretation of safety: “A killed-virus vaccine for poliomyelitis must be safe without qualifications. If it is admitted that it can be made safer, then it is not sufficiently safe.” He referred to the Cutter incident: “When such a tragedy occurs you do not continue operations as usual.”
David Oshinsky’s Polio: An American Story is a richer and more complex book than Kluger’s. Oshinsky’s position on the mythmaking? “I am trying to stay away from it,” he said in a recent conversation.
Salk emerges here as a complex scientist. He was an outsider, Oshinsky writes. “Salk was marooned out there in Pittsburgh, fiddling with an old-fashioned killed-virus vaccine and doing the dog’s work that his betters refused to do.” Yet he was close to the National Foundation for Infantile Paralysis and to O’Connor. He was meticulous in his science. “It was a game of trial and error, testing and tinkering, and few knew it better than Jonas Salk.” He was confident about his work but aware of its dangers. “ ‘When you inoculate children with a polio vaccine,’ he said later, ‘you don’t sleep well for two or three months.’” He was sensible and accommodating, yet he could be insensitive and egotistic, especially when dealing with his laboratory team. “Once the goal was reached, the group would split apart amidst charges that Salk had not appreciated, much less acknowledged, the collaborative nature of his success.” He shied away from the media yet craved publicity. “One of his greatest gifts was a knack for putting himself forward in a manner that made him seem genuinely indifferent to his fame, a reluctant celebrity, embarrassed by the accolades, oblivious to the rewards.”
All this Oshinsky unfolds in the context of the National Foundation’s politicking and lobbying, and of the larger politics of the day. In the end, Oshinsky’s Salk emerges as someone we care to know something about, most notably his left-wing leaning early in life (which Oshinsky learned about from FBI files), his apolitical stance in midlife, and his mystical tendencies in old age. Yet Oshinsky’s account has problems of its own. Although early concerns about Salk’s vaccine were scientifically motivated, those at the end of the 1950s were broadly social. An immunity gap among different social and economic classes had developed; Oshinsky knows this but gives the subject only two pages.
In 1959, epidemiologists reported findings on the pattern of the disease. These suggested a shift in incidence according to age, geography, and race. By 1960, less than one-third of the population under 40 years of age had received the full course of three doses of the Salk vaccine plus a booster. Most of those who had were white and from the middle and upper economic classes. The disease raged on in urban areas among African Americans and Puerto Ricans and in certain rural locales among Native Americans and members of isolated religious groups.
The gap had to do with access to vaccination. Pediatricians were not well compensated. “This was the one thing they could do which was a guaranteed reasonable flow of cash,” explained Henderson. The physicians resisted losing that cash; they argued for a vaccine that required their professional training.
Late in 1960, at the mid-winter clinical session of the American Medical Association, the surgeon general of the United States presided over a symposium on the state of polio immunization. E. Russell Alexander, chief of the surveillance section at the Communicable Disease Center, said, “The residual pattern of disease represents a measure of our failures to apply vaccine completely enough.” A. D. Langmuir, chief of the epidemiological branch at the center, said, “[P]olio seems far from being eradicated. The dreamed-for goal has not been achieved. In fact, many students of the problem question that eradication of poliomyelitis infection with inactivated vaccine is a scientifically tenable concept.” One of the main concerns was that the Salk vaccine did not prevent infection in the gut and thus did not break the chain of transmission.
Beginning in January 1962, pediatricians in two Arizona counties, Maricopa and Pima, containing the state’s largest cities, Phoenix and Tucson, conducted separate but similar voluntary mass immunizations using Sabin’s vaccine. “Previous programs in the county, using the Salk vaccine, had failed to bring polio immunization to a satisfactory level,” they reported a year later in the Journal of the American Medical Association. The program was called SOS (Sabin Oral Sundays). More than 700,000 people were immunized–75 percent of the total population in both counties. The vaccine was given at the cost of 25 cents, for those who could pay. It was given to population groups that were socially, racially, and culturally diverse, on Indian reservations and military posts and in urban and rural areas. The program became a model for subsequent U.S. mass-immunization programs. By the mid-1960s, Sabin’s vaccine was the only one in use in the United States. It was the Sabin vaccine that closed the immunity gap and effectively put an end to polio in the States.
Yet Sabin’s vaccine, too, has a problem. Attenuated live virus can mutate back into a virulent form. This has happened in a small number of cases. In the United States, therefore, after the decades in which the Sabin vaccine extinguished polio, the Salk vaccine is, ironically, once again preferred for immunizations. But the Sabin vaccine, cheap and easy to administer, is still the one used in the current campaign to eradicate polio worldwide. This campaign has extinguished the disease in the rest of the Western Hemisphere and in Europe, and almost entirely in Asia, though recent flare-ups in central Africa remain ominous.
Angela Matysiak is completing her PhD at George Washington University, in history of science, and is writing a biography of Albert Sabin.