Medicine: Polio Progress

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When a legion of doctors gathered in Chicago last week to swelter through the annual convention of the American Medical Association, they had not long to wait for the news that interested them—and their patients—the most. How is the Salk polio vaccine working out?

In a jampacked session on Navy Pier, four experts led by Vaccinventor Jonas Salk pronounced a favorable verdict. One year and 40 million inoculations after the initial flurry of accidents, controversy and fumbling, the vaccine has been vindicated. Said Dr. Salk in an unwontedly cautious, indirect statement: "Inferences that the theoretical considerations were unsound or were not applicable . . . seem not to have been supported by time."

Surgeon General Leonard Scheele of the U.S. Public Health Service happily backed up Salk's rebuttal to his nowsilenced critics (the most vociferous were not even invited to appear on the program). Since May of last year, when Scheele imposed stricter controls to guard against faulty vaccine, "there has been no ... evidence that any lot of [commercial] vaccine has been unsafe." From the millions of shots given to date, no more than one "suspicious" polio attack has come out of each big lot — a figure, according to Scheele, "well within the limit of expected coincidence."

Women & Children First. The main vaccine problem is supply, which is still far behind demand, although 69 million cc. have been released. Of the expanding monthly output (9,500,000 cc. in May), 60% now goes to public agencies for free clinics and distribution to local doctors. The rest goes through normal sales channels to druggists and M.D.s. Scheele urged doctors to give high-priority coverage to children under 15 and to pregnant women.

Scheele based his plea on heartening statistics. In studies covering 8,500,000 children in 22 states and New York City last year, the overall attack rate among vaccinated children, most of whom had but a single injection, showed only 6.3 polio cases per 100,000. Among the unvaccinated, the attack rate was almost five times as high: 29.2 cases per 100,000.

Eventually, every U.S. child can expect polio immunization, reported Dr. Salk. If properly administered, he said, the vaccine would give close to 100% protection against paralytic polio. In a 1955-56 study of 4,167 children, he found that only 4.8% had sufficient polio antibodies before vaccination. After the first shot, 43% had protection against all three polio virus types. After the third dose, administered a year later, 98.5% were found to have three-way immunity. Salk emphasized his prescription of a three-shot schedule: two shots two to six weeks apart, and the third about seven months later. But even one shot is far better than none, for it may protect the central nervous system (where polio does its worst damage).