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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Bacilli Calmette Guerin contains the avirulent strains of
assistant
The correct answer is  BCG is produced from strain Mycobacterium bovis Ref: Harrison&;s Principles of Internal Medicine; 19th edition; Chapter 202; Tuberculosis