There are two polio vaccines that are used throughout the world today. There is the oral polio vaccine and the injected polio vaccine. The injection vaccine was invented first. It was invented by Jonas Salk and first tested in 1952. It was announced to the world on April 12, 1955. The second vaccine was invented by Albert Sabin. This vaccine was the oral one. The oral vaccine was a scientific breakthrough at that time. The vaccine was began testing in 1957 and was introduced to the world in 1962.
The Oral Polio Vaccine was much more fit for the younger polio victims. …
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