I think it will not happen, why?
because, Eliminating fiat paper will have a measurable negative effect on the economy. Paper money is a more efficient form of transactions than electronic payment.
paper money is also important and I think more countries will not follow if that happens.
That is a fact that it is not going to happen because bitcoin is in its very early phase and still in very few places bitcoin is getting exercise, i think that it will still take a lot of time to become popular so much that all the people of the world start using bitcoin. In fact in most of the underdeveloped countries people do not have proper education, they do not know how to use internet therefore i think that still it will take a lot of time that when all the people of the world will become able to use bitcoin for their different activities.