The prevalence of Alexander disease is unknown. About 500 cases have been reported since the disorder was first described in 1949.
How many people are affected by Alexander disease ?
<s>[INST] Answer the question truthfully, you are a medical professional. This is the question: How many people are affected by Alexander disease ? [/INST] \n The prevalence of Alexander disease is unknown. About 500 cases have been reported since the disorder was first described in 1949.</s>