If you spot it in Wikipedia, point it out, it does get removed. Leaving a comment on the talk page <!-- or in the article --> gets editors on-board to patrol for accidental attempts to add the incorrect information back in. Wikipedia does not like https://en.wikipedia.org/wiki/Citogenesis
On the other hand, some of the best is when a hoax written by a monk in the north of England some time around 1300 is debunked by late 20th century scholarship, and eventually someone makes Wikipedia no longer re-hash a propagandist revision of the Battle of Stirling Bridge re-set in Wales that stood unchallenged for almost 7 centuries.