Bitcoin opens many doors of new markets, which would affect the economy of a country, the reason why there are some countries who don't like bitcoin because cryptocurrency controlled by no one and because they don't get taxes. But if governments open there eyes and use bitcoin in its positive ways as possible you would be shocked that the third world countries who opens their gates on bitcoin will become one of the best countries we have ever seen.
i really don't know if it will affect the whole economy. But i think, if the bitcoin becomes the currency, it might affect because it doesn't have any taxes at all. On the other hand, maybe it may become positive but no distinct reason why.