Dumb question

I might well be tripping or something, but I swear you could see when other players got poisoned (and other specific effects). I feel like I remember seeing the purple glow/effect flash on other people in videos and stuff whenever they get poisoned, but I haven't seen it happen whatsoever since buying the game a week or two ago.

Does anyone know whether the ability to see when poison effects hit people was removed, or was ever in the game to begin with?