What are the adverse effects of electrical current running through the human body?

Electricity is heat, it heats up the cells and kills them.

The electric currents running through our bodies and brains are the result of chemical reactions. And of course, some of the chemicals are leftover after our death, as well, the electric currents would have been lost as heat most likely. So I suppose you could call the remaining energy a 'ghost' but then you could just as easily call a muffin a ghost, since it too is made of chemicals and could have been heated by an electric oven. In fact, everything would be a ghost in that case (radio waves, plastic chairs, yogurt, concrete blocks, t-shirts etc) everything is made of chemicals and contains electric energy.

Um 100+ milliamps, um... death

Death !