<prompt> Acute onset headache, fever, seizure:MeningitisMigraineSubarachnoid haemorrhageEncephalitis  <response>: Encephalitis: Ref: 2480, 88, 247-73-2387-H 2621-22-H17thMeningitis: - Clinical triad fever headache and nuchal rigidity Stiff neck 90 of cases Seizures occurs as part of the initial presentation of bacterial meningitis 20 - 40 of patients Kernigs sign and Brudzinskis sign positiveSubarachnoid hemorrhage: - Most common cause of S AH is rupture of saccular aneurysm Sudden loss of consciousness, severe headache generalized, neck stiffness and vomitingNo fever Common deficits - hemiparesis, aphasia and abulia Focal deficits frequently absent 995 - CMDTMigraine: - Migraine, the most common cause of headache Headache, nausea, vomiting, photophobia, scalp tenderness is common symptomsEncephalitis: - Acute febrile illness, meningitis features, confusion, behavioural abnormalities, altered level of consciousness, focal or generalized seizures occurs in severe encephalitis Focal finding aphasia ataxia, hemiparesis, cranialnerve palcies ocular palsies, facial weakness 2480 - H 