Well, the thing is that when Columbus returned he, and everyone else, thought he discovered only some islands near Asia, not really America. So your question may be interpreted two ways:
Which I touched on this old answer where I talk briefly about the incredibly fast rate of reprinting the Columbus letter around Europe:
We do know is that Columbus letter announcing his discovery was a major hit all over Europe, being quickly translated to Latin in Rome, and from there being republished in many other countries.
As stated on this webpage:
Christopher Columbus's 1493 announcement of the success of his voyage westward across the Atlantic Ocean quickly became one of the earliest 'best sellers' of European publishing. No less than eleven editions were published in 1493! They were issued across western Europe, in Spain, Italy, France, Switzerland, and the Netherlands. Six more editions were published in 1494-97.
And the article is accompanied by a nice infographic showing how much and how fast the letter publication spread. From this it is obvious that Columbus letter was read and known in many corners of Europe. But just how much read and known is impossible to guess just from looking at the publishing numbers.
The other way we can look at your question is:
This I covered in this answer, where I mention that it is only by 1502-1503 and Amerigo Vespucci that a realization of existence a whole new continent (initially Southern America) fully materialized, and even then it took few more decades to be sure North America is not just part of Asia.
