The United States was declared 'polio-free' in 1979 – almost 43 years ago.
However, in what officials are calling "going back in time," New York Governor Kathy Hochul declared a disaster emergency on 11 September, after the polio virus was detected in wastewater samples from four counties.
In July, one person was found to be infected with polio in New York state's Rockland County in July, due to which the government began wastewater surveillance.
Why is this concerning? What are the reasons for this? FIT breaks it down for you.


