I came across this research on sleep disorders and things you can do and things to avoid to help with sleeplessness - which is a frequent side effect of encephalitis.
I often lie awake till 3am and then sleep till noon even with exercise. Pills don't work and are pretty ill-advised for long-term use. I'll try some of these measures and see if they help. Thankfully cold showers in the morning are most beneficial to those under 60 years old.