Feb 19, 2013

Scientists have created new strains of polio.

New Polio Strains That Protect Vaccine Factory Workers. Scientists have created new strains of polio intended to protect workers in factories that make polio vaccine. The new strains have the same ability to invoke an immune reaction as the live viruses now used to make vaccine do, but there is virtually no risk anyone will get polio if one of the new strains somehow escapes. 

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