What caused polio virus in 20th century

Like a horror movie, throughout the first half of the 20th century, the polio virus arrived each summer, striking without warning. No one knew how polio was transmitted or what caused it. There were wild theories that the virus spread from imported bananas or stray cats. There was no known cure or vaccine.

Explanation:

1894, first outbreak of polio in epidemic form in the U.S. occurs in Vermont, with 132 cases. 1908, Karl Landsteiner and Erwin Popper identify a virus as the cause of polio by transmitting the disease to a monkey.

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chapter i -- paris: september, 1792

a surging, seething, murmuring crowd of beings that are human only in name, for to the eye and ear they seem naught but savage creatures, animated by vile passions and by the lust of vengeance and of hate.

during the greater part of the day the guillotine had been kept busy at its ghastly work: all that france had boasted of in the past centuries, of ancient names, and blue blood, had paid toll to her desire for liberty and for fraternity.

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