so what happens if someone is killed. That person turns, and shit hits the fan again.
In this situation, assuming everyone turns when they die, they'll have to start up a system to ensure the brain is destroyed for everyone. Maybe large euthanasia centers, for when people are too sick/injured to recover, or maybe everyone has to do a daily "life check" to make sure no one secretly dies. Anyone missing, sets the town/state/country on a high alert, to either find the missing person (or find the walker and destroy it).
Could eventually make everyone wear a heart monitor, that sends out either a gps signal (or sets off an implanted explosive device), if someone's heart stops for a few hours.
Basically, constant, unending vigilance against unplanned/isolated death.
Or maybe just cure the disease, and give everyone a vaccine, where turning never happens again.