Oh wait, but it's the game, not the series, right?
That's interesting, I was thinking game was also using the original "kurwa" as in the books.
If Polish game version decided to go with "zaraza", which directly translates to "plague" in Polish, and is rather archaic form, this explains why they used the same in Russian.
And game might have gone for "zaraza" to bypass age restrictions 馃槂