My area has recently seen 3 children at 2 separate facilities present with eerily similar and so far undiagnosed problems. Similar age group, but nothing else in common (different locations, ethnicities, no similar contacts or travels, etc.)Presentation: 2-3 day history of fever, c/o headache, occasional vomiting. ER admission due to changes in level of consciousness or physical mobility. Work-up: CT, MRI, LP, pan-cultures, viral panel of CSF, blood and secretions, standard lab work-up. All repeated after a few days of admission. Regular blood cultures. All results unremarkable. WBC's normal, CRP mildly elevated in 1-2 patients, CT and MRI normal, spinal fluid clear, cell count, protein, glucose results normal. All cultures and panels persistently negative. Treatment: Broad-spectrum antibiotics and antivirals including max doses of vancomycin, ampicillin and acyclovir. Course of stay: Progressive decline in neurological status. Most recent presenting patient deteriorated from oriented and physically appropriate to a GSC score of 6 within 8 hours. Seizures in the first 2 presenting patients. Loss of ability to maintain airway. Intubated for currently 2 weeks and 4 weeks respectively. We are all at a loss. Does anyone have any insight?