It was largely eradicated almost 50 years ago, but the crippling disease polio is making a comeback. 
The polio virus has been discovered in London, Jerusalem and New York state, where officials have declared a health emergency. 
Today, the health commissioner from the US county where there are already hundreds of cases on what needs to be done to stop the worldwide spread. 
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Dr Patricia Schnabel Ruppert, epidemiologist and health commissioner, Rockland County, New York