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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
The most common cause of sporadic viral encephalitis is :
assistant
The correct answer is  “The most common virus causing sporadic cases of encephalitis in immunocompetant adult are HSV-1, VZV, EBV and less commonly enterovirus.”
Remember: Epidemic of encephalitis are caused by Arbovirus which include:

Alphaviruses
Toga viruses
Bunyaviruses