"(world) vice-champion" is to be found on loads of websites, but most of them seem to be non-native-speaking...

Following their defeat Germany finished as runner-up to World Champion Brazil.

world vice champion doesn't sound right to me - more like a very literal translation

Juan Antonio Navarro is Monopoly world vice champion until a new runner-up emerges at the Monopoly World Championship in Toronto this year.

from a US-Website

Vice-champion? I don't like it; it sounds like it could mean Weltmeister der Unsitten.