Where one plays Counter-Strike or Counter-Strike: Source for long periods of time in a Zombie-like state. You may not be seen for a long while as you will spend every moment, that is not spent doing otherwise, playing CS or CS:S. The remedies for the "sickness" are:
1.) Un-install it and do something else.
2.) Find something that over-powers the urge to play CS.
3.) Go outside and have some fun.
There may indeed be other remedies, but these are the best. Now stop playing CS and go outside!
Counter-Strike zombie: in my 3 weeks offline i pwned hundreds of n00bs with my l33t deagle skills!
Internet forumer: That guy has the Counter-Strike sickness.
Random funny comment guy: Hey, come on, get up, get down with the sickness! :D XD :p
Counter-Strike zombie: n00bs! im going to go play cs, i dont have tiem for dis!