For those of us under the age of 50, it is difficult to imagine how the fear of polio once pervaded American society. But during the postwar years especially, polio was an almost constant concern, on par with communist “subversives” or atomic war. Given that this fear often bubbled over into near-hysteria, it is clear why Dr. Jonas Salk, who devised the first polio vaccine, became (at least temporarily) a national hero.

The first epidemics of poliomyelitis – or “infantile paralysis” – in the United States arose in 1894 in Brooklyn and Vermont, and the cities of the Northeast would always remain identified with disease. At one point, in 1916, Rhode Island and three other states even banned children from New York from crossing their border without a note from their Department of Health.

Polio was caused primarily by contaminated drinking water, but during its heyday that was not known; it remained a mysterious disease that struck active, middle- or upper-class children with paralysis and death.

And so every summer, when polio was at its most contagious, children were forbidden from swimming, or going to the movies, or even visiting the library – practically everything that allowed a break from the heat. Even during cooler months, children were confronted with the disease. Leg braces and crutches were a common sight. Movie theaters showed newsreels about “the man in the iron lung,” whose upbeat smile could be seen in the mirror affixed to his enormous respirator.

Certainly the actual threat of the disease was exaggerated. In “Polio: An American Story” (Oxford University Press, 368 pages, $30), David Oshinsky reminds us that, even in the 1940s and 1950s, “ten times as many children would be killed in accidents … and three times as many would die of cancer.” But after reading the first person accounts in Daniel Wilson’s “Living with Polio: the Epidemic and Its Survivors” (University of Chicago Press, 320 pages, $29), I’m not surprised Americans were scared.

Polio began with relatively mild symptoms, like a sore throat, a mild fever, or a stiff neck. For most, the worst would be over in a few days. But for others, the pain increased until it was excruciating. (According to Mr. Oshinsky, when Franklin Delano Roosevelt took sick, “he couldn’t tolerate the feel of his pajamas or the rustle of a breeze.”) Then came the first stages of paralysis: A victim would realize that he could no longer button his shirt or walk to the bathroom.

The “best” way to diagnose polio was through the painful and often traumatic procedure of a spinal tap. A positive result meant additional trauma, especially for children: They would be immediately quarantined. As described by Mr. Wilson’s “polio narratives,” life in the isolation ward consisted of agony and terror. Patients whose breathing muscles had been paralyzed were put in iron lungs, which forced air in and out of the body with air pressure on the chest. Literally every bodily function was impossible without the aid of a nurse – a humiliating position for anyone, no matter how kind the staff.

And some were not so kind. Mr. Wilson quotes one Hugh Gallagher, whose therapist tested his ability to breathe on his own only after he had fallen asleep. Then “she would turn off the respirator and, with a stopwatch, time how long it was before I awoke from suffocation.” Even less sadistic health professionals relied on techniques that now seem almost medieval. Throughout the 1930s, those with “lesser” forms of paralysis had their limbs immobilized by splints, casts, and other kinds of restraints. (Richard Owen, 12 when stricken with polio, had both legs immobilized for nine months.)

The treatment of paralyzed extremities improved somewhat with the arrival of Elizabeth Kenny, an Australian semi-charlatan whose snake oil actually worked. “Sister” Kenny had dubious nursing credentials and an abrasive manner, but she also had a way with her patients, and what Mr. Oshinsky calls a “remarkably keen sense of human anatomy.” Her treatment consisted of applying hot, wet wool packs directly to the affected limb, followed by gentle stretching. The regimen often restored some strength and flexibility, but it had its dangers: Mr. Wilson relates instances of children being scalded by the boiled wool, and of terrible itching as it cooled.

Mr. Oshinsky’s “Polio” and Mr. Wilson’s “Living With Polio” are only two of many books being published on the 50th anniversary of the vaccine. Mr. Wilson, a history professor at Muhlenberg College and a polio survivor himself, has done an admirable job of assembling more than 150 first-person accounts into a coherent narrative. He recounts every stage of the disease, including a chapter on “post-polio syndrome,” a mysterious resurgence of muscle weakness that assails many polio victims decades after they have accepted – and often overcome – their disabilities.

Yet Mr. Wilson has almost done too good a job. There are too many voices in “Living with Polio,” and many of their stories are too similar. Had Mr. Wilson selected only three or four accounts or been more generous with his own, he may have narrowed the scope of his book and done away with a good amount of repetition.

Mr. Oshinsky does not ignore the victims of polio, but he spends much more time on the outsized personalities associated with the disease. He provides brisk, engaging biographies of major figures, from Roosevelt to Basil O’Connor (the brilliant workaholic who ran the March of Dimes) to Dr. Salk and his competitors. He tells the stories of polio’s effects on American culture, from the ascent of minorities in the professions (Dr. Salk and his two main rivals were Jewish; O’Connor was Irish-American) to the rise of corporate philanthropy and public relations.

In the America of 2005, new cases of polio are extraordinarily rare; the World Health Organization hopes to eradicate it completely by 2008. But Mr. Wilson reminds us that more than half a million Americans are still living with its consequences. And Mr. Oshinsky shows that, in many ways, we all are.

Mr. Haber last wrote in these pages on the Gulag.