WASHINGTON, April 28, 1955 (UP) -- The Public Health Service urged parents today to go ahead with any plans they have to get Salk polio shots for their children. It said they can have complete faith both in the effectiveness of the serum itself and in the vaccination programs now under way throughout the country.
The health service made the statements in a frank effort to calm a wave of concern and uncertainty set in motion yesterday by a government ban on all vaccine produced by Cutter Laboratories in Berkeley, Calif.
The ban was ordered as one child died and at least nine and possibly 11 suffered paralysis from polio after receiving Cutter vaccine. Government experts don't think the serum is responsible, but they want to be absolutely sure.
Two health service specialists were rushed to California last night to make a detailed study of the company production methods. And the National Institute of Health began running tests here today to check samples of its vaccine for safely, purity and potency.
Officials also revealed they are considering a plan which could eliminate the need for a ban on a firm's vaccine. This calls for creation of teams of experts equipped to investigate a polio case so quickly the vaccine could be removed as a suspect in a matter of hours.
Government officials aimed their biggest effort, however, at maintaining public confidence in the Salk program as a whole so as not to jeopardize polio protection for the nation's children this year.
No sooner was the federal ban announced yesterday than authorities began calling back Cutter vaccine in 43 states where it was distributed. Parochial schools in Philadelphia temporarily halted a mass inoculation program.
And doctors and parents besieged the health service with one question: Should Salk shots be continued?
Dr. Leonard A. Scheele, U.S. surgeon general, said the answer is yes. His own 7-year-old son, Bobo, will be inoculated shortly in the program here.
Scheele said some deaths and some cases of paralysis must be expected this year because the vaccine is not 100 % effective. But he said it is 80 to 90 % effective and therefore is a very useful weapon against polio.
Scheele predicted more cases of polio will crop up in vaccinated children and that they will involve serum produced by firms other than Cutter.
The cases of paralytic polio which prompted the Cutter ban were reported in Chicago, Denver and in four California cities - Ventura, Napa, Oakland, and San Diego, where there were two cases. The death occurred in Pocatello, Ida.
Dr. Jonas E. Salk, the vaccine's developer, said in Pittsburgh "it is difficult to say" whether the vaccination in these cases was "one of cause and effect or of coincidence." He endorsed the federal investigation.
Government officials said the vaccine probably is not to blame in any of the cases, although they won't know for sure until their inquiry is completed several weeks from now. Here are their reasons:
Number of shots: The children generally received only one shot. The vaccine's peak immunity is not reached, however, until three shots have been administered over a seven-month period.
Timing: The children were inoculated between about nine and 15 days ago. Salk shots develop very little immunity after so short a period.
Incubation period: The incubation period of polio - infection to onset - ranges from 3 to 30 days and averages between 10 and 14 days. It is believed in the vaccinated cases that the children may well have contracted polio before they received their shots.
One polio expert pointed out that in Southern California - where most of the 11 cases occurred - polio is endemic. That is, the polio viruses are active year round.
But, for the week ending Apr. 16 - which was about the time the children were being vaccinated - only nine polio cases, three of them paralytic, were reported in the entire state. Idaho reported no cases.