Medicine: Vaccine Free-for-AII

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The U.S. Public Health Service last week licensed the manufacture of a live-virus vaccine, to be taken by mouth for protection against one of the three types of poliomyelitis. Developed by the University of Cincinnati's Dr. Albert Sabin, the licensed vaccine is manufactured in England by a subsidiary of New York's Charles Pfizer & Co., which will distribute it in the U.S. Since it is the first oral vaccine approved for general distribution, its licensing would seem to be a major step forward in the battle against polio. But the effect of the Government action was to throw the already confused polio vaccine situation into worse confusion.

The trouble with the newly licensed vaccine is that it is effective against only Type I poliovirus. Said the PHS's Surgeon General Luther L. Terry: "I want to emphasize that an oral vaccine providing protection against all three types of poliomyelitis will not be available for some time. It is of the highest importance that vaccinations continue with the Salk vaccine, which is the only weapon we have today against all three types of polio."

Strict Safety Test. Type I poliovirus used to cause 85% or more of all paralytic polio; Type II caused less than 5%; and Type III was blamed for the rest. Now Type II has all but disappeared, and Type III is reported as causing more than half of the paralytic cases. Why is not yet certain; one suggestion is that the injected Salk vaccine, which combines the three types in a single shot, was often weakest in its Type III component.

Dr. Terry said he expected the oral Type II vaccine to be licensed "in the near future," but that is now a relatively irrelevant matter. The issue is oral Type III. All vaccine batches are brewed separately by types, and samples are sent to the PHS's Division of Biologies Standards for testing of safety and potency. The toughest safety test is to inject vaccine directly into the brains of monkeys. If autopsies show any appreciable virus damage to the monkeys' nerve centers, PHS orders the vaccine discarded. Type I vaccine has already passed this rigorous test the required five times; Type II is nearing the finish line. But for reasons unknown, Type III vaccine, from all manufacturers so far reporting, retains some power to damage monkey brains, even though it has been given to almost 100 million people (mostly in the U.S.S.R.), apparently with no ill effects.

Waiting Till Spring. The monkey-brain test is admittedly arbitrary, because no human being is likely ever to get the vaccine that way, even by accident. So some experts would like to see it dropped. Vaccinventor Sabin calls it "an insignificant test." But Dr. Jonas E. Salk tried in vain to block general release of any oral vaccine this year except for an emergency stockpile for Government controlled use in epidemics. The National Foundation's Basil O'Connor snorted: "It is totally unorthodox to license part of a vaccine." Some manufacturers guessed that release of Type III oral vaccine cannot come before spring.