The Polio Vaccine 1955 – Poliovirus

Polio is a viral disease that can result in muscle paralysis. Nearly 58,000 cases of polio were reported in the United States in 1952. While 21,269 people were left with mild disabilities, 3,145 children died. At the time, Americans regarded only the atomic bomb as worse than polio. 

When the existence of an injectable vaccine was announced on radio and television on April 12, 1955, according to physician Paul Offit,"church bells rang across the country, synagogues and churches held prayer meetings, and parents and teachers wept."

Polio has affected humanity since prehistoric times, as illustrated by ancient drawings and paintings in Egypt depicting children with wasted limbs walking with canes. Three different types of poliovirus can enter the gastrointestinal tract through contaminated food or water and then spread to the central nervous system, causing paralysis. Depending on which nerves are infected, the virus can paralyze only the legs or almost the entire body, making it impossible for a person to breathe without mechanical assistance.

Today, two types of vaccines are used to combat the virus:

• One is a vaccine based on inactivated virus, developed in 1952 by American medical researcher Jonas Salk. Salk cultured poliovirus in monkey kidney tissue cells and chemically inactivated it with formalin. When the inactivated forms of the three viral types are injected, the body develops antibodies against the three live forms. 
• The other is American medical researcher Albert Sabin's oral polio vaccine (OPV), based on forms of the three polioviruses that replicate in the intestine and have been "attenuated".

Today, because the attenuated virus in OPV can revert to a paralysis-causing form in very rare cases, many industrialized countries use the injectable vaccine. Widespread vaccination has made polio rare in the Western world.

Historical Figures Mentioned in This Article: Albert Bruce Sabin (1906–1993), Jonas E. Salk (1914–1995)

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