Video: 'The fight against Polio - 1953 | Movietone Moment | 26 March 2021'

(Thursday, March 26, 1953) — A vaccine against polio that has been used safely and successfully in preliminary trials on ninety children and adults, producing protective immunity bodies against all the three viruses causing the disease, was announced tonight at a special meeting at the Waldorf-Astoria Hotel in New York City under the auspices of the National Foundation for Infantile Paralysis.

The vaccine, one of the great landmarks in the story of man’s battle against disease, was described by Dr. Jonas E. Salk, Professor of Research Bacteriology at the University of Pittsburgh, who headed the team of scientists in developing the vaccine, with the aid of March of Dimes funds.

There are three types of polioviruses, known as Brunhilde, Lansing, and Leon. The vaccine has been found to provide protection against all three.

In many cases, Dr. Salk reported, the number of antibodies (immunity factors) produced by the vaccine was greater than the number produced naturally in persons who had been exposed to one or more of the viruses.

Dr. Salk warned, however, that much further experimentation will be required before the vaccine could be safely given to the public.

Video: 'Jonas Salk, Polio Conqueror | San Diego Union-Tribune'

“Although the results obtained in these studies can be regarded as encouraging.” Dr. Salk said, “they should not be interpreted to indicate that a practical vaccine is now at hand.

“However, it does appear that at least one course of further investigation is clear. It will now be necessary to establish precisely the limits within which the effects here described can be reproduced with certainty.

“Because of the great importance of safety factors in studies of this kind. it must be remembered that considerable time is required for the preparation and study of each new batch of experimental vaccine before human inoculations can be considered,” Dr. Salk said.

These considerations indicate that it may take at least another three years before the vaccine can be made available safely for general use.

In 1954, Salk tested the vaccine on about one million children, known as the polio pioneers.

The vaccine was announced as safe on April 12, 1955. Following the introduction of polio vaccines in the 1950s polio incidence declined rapidly.