33
/ru/
AIzaSyB4mHJ5NPEv-XzF7P6NDYXjlkCWaeKw5bc
November 1, 2025
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polio
Category:
Иное
Обновлено:
26 ноя 2017
1
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476
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Created by
Sophie
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eee
By
Sophie
26 ноя 2017
0
0
507
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Polio was the most feared disease of this time.
Jonas Salk announced that he was developing a trial vaccine for polio.
The Salk vaccine was tested on 1.8 million schoolchildren.
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