This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'Under national polio eradication programme, a case of acute flaccid paralysis is confirmed as polio by surveillance after how many days? \nSelect and explain. \nA. 15 days, B. 30 days, C. 60 days, D. 90 days', 'role': 'user'}, {'content': 'Answer: C \nExplanation: 60 days REF: Park 20\' edition page 177, 178, Infectious disease surveillance - Nkuchia M. M\'ikanatha Page 507, www.npspindia.org "As soon as lab results and (when required) 60-day follow-up repos are available, the cases are classified at NPSU as polio or non-polio AFP. Cases with inadequate specimens are reexamined at 60-days; if no residual weakness is found, the case is discarded as non-polio AFP. Beyond 60 days after paralysis onset, the likelihood of detecting poliovirus is very low"', 'role': 'assistant'}]