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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
B19 usually causes a very mild disease. Two groups of people for whom it can be serious, however, are?
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The correct answer is  Primary infection in pregnant women is very serious and can result in death of the fetus. In patients with sickle-cell disease, the virus can initiate a transient aplastic crisis. Reference: Ananthanarayan and Paniker&;s Textbook of Microbiology Tenth edition