Objective: Eastern Equine Encephalitis (EEE) is a rare but potentially fatal mosquito-borne virus when transmitted to humans. There are no longitudinal studies regarding the neuropsychological functioning in children with EEE. CB was infected with the virus which resulted in coma, seizures, tremor, fever, and respiratory insufficiency. He had elevated white blood count and hypogammaglobulinemia, which was treated with IV immunoglobulin. Seizures included right sided tonic/clonic activity, staring spells, and EEG evidence of left temporal spike discharges. Over a 4 week recovery, he had transient aphasia, swallowing dyssynergy requiring gastrostomy feeding, Parkinsonism, and right hemiparesis. MRI scan on admission showed FLAIR imaging evidence of white matter change reminiscent of leukodystrophy at the anterior and posterior portions of the parietal centrum semiovale. Two years following diagnosis, CB also tested positive for Lyme Disease. Method: CB underwent neuropsychological evaluations across four time epochs. Results: While CB's verbal skills have remained in the extremely low range, his perceptual reasoning skills have fluctuated significantly. Visual motor, processing speed, and memory skills have remained very weak. Conclusion(s): CB has received intensive intervention for 9 years following virus contraction. While improvements were made in right hemisphere related tasks, such as perceptual reasoning, there were minimal improvements, with periods of regression, in verbal tasks suspected to be the result of ongoing seizure activity in the left hemisphere. Additionally, behavioral decline and emotional dysregulation were noted and were thought to be related to increased right frontal hypomyelination.