In a recent interview, Sean Waltman reveals that he is unable to perform for TNA because he has contracted the heptitiis C virus, which attacks the liver. Since it is a disease that is transmitted via blood, it's a wise move to keep him away from other performers.
No word yet on when or if Sean Waltman will return to TNA. Management is currently satisfied with Eric Young as his replacement in the Band (with Kevin Nash & Scott Hall).
Source wrestlingrevealed.com
Full article - http://www.wrestlingrevealed.com/next/content.php?659-Sean-Waltman-Explains-Absence
I feel sorry for him, I hope he gets better soon. What a great in ring talent, he had just got his life together as well.