<prompt> Definite case of Polio is considered if -Paralysis is for more than 6 weeksAntibody titre is more than 4 times of normal valueDemonstration of Polio virus in stoolAcute encephalitis with paralysis  <response>: In early stages polio is differentiated from other forms of AFP by analysing fecal specimens for the presence of polio virus. Two specimens are taken 24 hrs apa during to the first two weeks. Antibody titre acts as a suppoing evidence and cannot be used for early diagnosis of the disease. All the other options given above are non specific for polio. Hence a definite case of polio is considered if polio virus can be demonstrated in stool. Reference: Parks textbook of preventive and social medicine. 23rd edition. Pg no:203 