ServerBlight, or "Blight" for short, is sort of a "virus" inside Team Fortress 2. Which is capable of assimilating players and capturing (and, by far, torturing) them in-game.
It is yes unknown HOW OR WHEN Blight appeared in the first place. But my first sight of it was on pl_thundermountain. As for now it was seen most active on following maps:

— ctf_sawmill
— pl_thundermountain
— pl-snowycoast
— koth_sawmill

I beg you. If you see DOZENS of name joining in, and you see the following nicknames:
— Syrenix, directionz, GUILLIESUIT, JohnyDany12, scubamaster64, Hector0n.
GET. OUT. OF. BOUNDS.
It shouldn't get to touch your characters body. The best way to do so is by jumping of maps edge... If there's NO way to easily get your body Out Of Bounds (example: koth_sawmill and ctf_sawmill) - Get your ragdoll Out Of Bounds by rocket-jumping. But don't get yourself gibbed (a.k.a don't deal any crit damage to yourself while rocket-jumping). Gibs are enough for it to assimilate you.

There are currently a few escape tactics known to me. So listen carefully. There's nothing hard to understand.

1 — Jump out of maps edge. Simple as it sounds, just jump into the nearest pit or of in-game cliff. Best to do on pl_thundermountain and pl_snowycoast.

2 — Get your ragdoll out of bounds. Simple as the first one, of there's no easy Out Of Bounds access through instakill pits etc. - Rocketjump so your dead body would go out of bounds, it will instantly get you out.
NOTE: DO NOT GIB YOURSELF. DO NOT GIB YOURSELF. BLIGHT *WILL* CATCH YOU ! ! !

... There's no other methods as for now... Sorry. Keep yourself save guys. Stay away from the Blight at all cost and help those who don't know about it.