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
You are the medical officer of a PHC in Kerala and you confirm the diagnosis of polio in one of your patients. This can be considered as: 
Select and explain. 
A. Endemic, B. Epidemic, C. Sporadic case, D. Pandemic
B: Epidemic
Answer: B: Epidemic 
Explanation: Here this disease is an unusual occurrence in the community and is clearly in excess of the expected frequency. So even a single case of polio is an epidemic as per definition. A sporadic case means the case occurs irregularly, haphazardly from time to time and generally infrequent. Ref: Park, Edition 21, Page - 89