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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
All the following are true regarding Type A influenza virus, EXCEPT:
assistant
The correct answer is  There are 16 subtypes of hemagglutinins. Rest of the statements given are true. Antigenic changes occurs only to a lesser degree in group B influenza virus. Influenza C virus appears to be antigenically stable. Note: Almost all of the pandemic which has ever occurred is due to Type A influenza virus. Ref: Park, Edition 21, Page - 143,144