crazy trainer is not infected
i have been using that trainer for about 2 years and nothing! plus i use crazy trainer to other games too, so maybe you just screwed something up before you reinstalled the game? did you instal any mods? if you did you have to reinstal and remove all remaining files of GTA:SA. if you moded your main.scm file and stuff like that, sometimes they stay eventhough you uninstal the game because they have been changed