<prompt> Polio is said to be eradicated if no case of polio by wild poliovirus occurs in an area for ?1 year2 years3 years4 years  <response>: Ans. is c i.e., 3 years Ceification of polio eradication is conducted an regional bases. Each region can consider ceification only when all countries in the area demonstrate the absence of wild poliovirus transmission for at least three consecutive years. 