Near-Disaster

Just as the Public Health Service was using one hand last week to press the starter button and get the stalled polio vaccine program running again, one of its spokesmen disclosed how close the U.S. had been to unimaginable disaster. Dr. William H. Sebrell Jr., director of the PHS's National Institutes of Health, testifying before a House committee, in effect answered the question that for a month had haunted U.S. parents: was the Salk vaccine safe? Answer: no, not under testing procedures so far used. Sebrell admitted that the safety tests originally developed for the 1955 Salk vaccine had proved to be "less than satisfactory," and also that the margin of safety built into the minimum standards was "no longer dependable."

No specific reason has yet been found to explain why two lots of vaccine made by California's Cutter Laboratories should have touched off polio infections in so many cases (69 at week's end), but Dr. Sebrell went on:

1) the slipup, whatever it was, could have happened to any manufacturer, and

2) would not have been detected by the established tests.

From all sides he had heard manufacturers report failures "for no apparent reason" in the process of inactivating the virus, i.e., making a safe vaccine. A manufacturing rival of Cutter said with commendable candor: "There is absolutely nothing to indicate that Cutter testing was not adequate. If that's so, then what happened to them could have happened to any one of us."

If it had happened to all at once, the U.S. might have had not a hundred but thousands of cases.

Tenfold Step-Up. While these disclosures were being made as unobtrusively as possible, PHS officials succeeded in beating down opposition by some of the vaccine makers so that all eventually accepted amendments to the testing procedures. (If Cutter makes and tests vaccine according to the revised specifications, it can get back into the business.) Spokesmen for both sides had been chattering all week about the new procedures being simply a question of interpretation--as Dr. Jonas E. Salk put it, "like reading the fine print in an insurance policy." But this was not so. The changes, as finally announced, were substantial:

P:Manufacturers can no longer mix for--maldehyde with the virus, leave it, and test the product afterward to see whether the virus has been inactivated: they must make intermediate tests during the process to see that the virulence is going down.

P:Before single-strain vaccines (representing each of the three main types of polio virus) are mixed to form the triple-threat end product, there must be more tests, using much larger volumes of material. Formerly, one-tenth of 1% of each strain was taken for testing; now, a minimum of 500 cc. must be used--a tenfold increase for a firm making vaccine in lots of 150,000 cc., and probably some increase for all manufacturers.

P:After the three separate strains are pooled, at least 1,500 cc. must be tested. Previously, there was no specified minimum amount, but one-tenth of 1% would have satisfied the wording. This change also could mean a tenfold increase.

P:All makers must use one of three preservatives. (Some omitted them after Merthiolate, used last year, was shown to have made much of the vaccine worthless.)

To give the manufacturer a break, because of the chance that stray virus in the air of his labs may give him a false positive test, he need not throw away a batch of finished vaccine after a single unfavorable test. He can have it tested in other labs, and if two successive tests are favorable, submit the batch for U.S. approval.

Safe, Safer? The more the authorities congratulated themselves on the new tests, the more (by implication, at least) did they condemn the old. PHS's Dr. James Shannon said that the revisions provide "more frequent and sensitive testing on what we now believe to be a more rational basis." Surgeon General Leonard Scheele called it "making a safe vaccine safer."

Use of the original "safe" vaccine had been followed by 113 cases of polio among the vaccinated. Last week an additional ten were among Cutter subjects. But because four full weeks had passed since Cutter inoculations were stopped, and the incubation period for polio is rarely more than 31 days, it seemed more likely that in the new Cutter cases the trouble was not defective vaccine, but the absence of a second shot in time to prevent a natural polio infection.

Across the country, the needlework that the National Foundation for Infantile Paralysis had sought to hasten for 8,500,000 first-and second-graders was being stilled. More and more parents were withdrawing permission. Virtually all the vaccine that had been approved and re-approved was used up. Dr. Scheele was confident that some vaccine, already finished, could be released by the middle of this week, and that the flow would increase rapidly. But all sights had been lowered: the best he could hope for was completion of the foundation's priority program by Aug. 15. All manufacturers, he forecast, would be slowed down by the stricter safety standards. Against this background, congressional proposals for ever-bigger Government bounties to give vaccine free to poor children added up to wind and politics. Equally inappropriate, because premature, was the congressional love feast, exculpating all concerned in the vaccine difficulties.

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