Complex sentence: Shackleford and Sissy are dying from a virus in their blood which is very lethal to this new race of cybernetic Tripods, and before he dies he convinces George to inject his infected blood into himself.
Split into simpler sentences: Shackleford and Sissy are dying from a virus which is lethal to the Tripods. Before he dies he convinces George to inject his infected blood into himself.