Technically, Ethan died in 7, remember? You learn that Jack killed him but he kept on due to the mold. Ethan was a walking mold bioweapon, in a way. Explains why he can just glue his hand back on over and over.
Is he really dead tho? Who was the mysterious hitch hiker at the end of the epilogue?? Rumors man. DLC should answer some of these questions.... maybe