Acyclovir improves outcomes in HSV encephalitis [0], but does not completely cure it or prevent long-term damage in all patients.
The worst side effect of encephalitis is memory impairment:
> The most common and most disabling complication of herpes simplex encephalitis in our patients, and in other studies,9 10 20-24 was memory impairment, which especially affected short term memory. Occasionally remote memory is more severely affected than anterograde memory.