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: Microbiology
[{'content': 'The characteristic features of El tor cholera are all except \nSelect and explain. \nA. More of subclinical cases, B. Moality is less, C. Secondary attack rate is high in family, D. El tor vibrio is harder and able to survive longer', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Secondary attack rate is high in family El Tor vibrio . It is much hardier than classical vibrios, capable of surviving in the environment much longer. . The severity of illness is much less, with a large propoion of mild and asymptomatic infections. . Moality is low and the carrier rate is high. . Fewer secondary cases in affected families (secondry attack rate is less) - Park", 'role': 'assistant'}]