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
What is the recommended period of isolation for shigellosis? 
Select and explain. 
A. Until 1 negative stool culture., B. Until 2 consecutive negative stool cultures, C. Until 3 consecutive negative stool cultures, D. None of the above
C: Until 3 consecutive negative stool cultures
Answer: C: Until 3 consecutive negative stool cultures 
Explanation: In cases of shigellosis and salmenollosis, the recommended period of isolation is until 3 consecutive negative stool cultures. Ref: Park 21st edition, page 110-111.