To those saying that the blurry screen is not a bug: In this case, it is. This is not the winded/dying blurry screen. It can happen to anyone, healthy or not. I have experienced it with healthy characters. It only happens after logging in to a server. Sometimes, the screen is more or less blurry. I have found that this blurry screen is far worse than any intended screen effects, and have never experienced that level at any other time. Sometimes, the screen doesn't show at all and instead presents a solid color, usually a puke green. This also goes away if you open the video settings.

I also have this bug. The blurriness will persist until the video options menu is opened. I played for a long time with the screen blurry, thinking it was part of the game, but I eventually got fed up and went to the video settings menu, and the game immediately sharpened.