Question

the different procedure of polio vaccination in current scenario as well
as before 20 years.​

Answer 1

Answer:

Between 1917 and the early 1950s several therapies were explored in an effort to prevent deformities including hydrotherapy and electrotherapy. In 1935 Claus Jungeblut reported that vitamin C treatment inactivates the polio virus in vitro, making it non-infectious when injected into monkeys.

Explanation:

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