Sixty years ago this month Dr. Jonas Salk's polio vaccine was declared safe and effective. It has since been given to billions of children around the globe. And, as VOA's Carol Pearson reports, in just a few years, the entire world could be polio free.
from Voice of America http://ift.tt/1PpBa6g
from Voice of America http://ift.tt/1PpBa6g
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