Sommerfield (Natasha Lyonne) has come up with a virus that can wipe out all of the vampires in the world, but it must be mixed with Drake/Dracula's (Dominic Purcell's) blood to reach full potency. Sommerfield warns Blade that he might also be killed by the virus, because he is a hybrid. At the final showdown with Drake, while Drake is fighting with Blade, Abigail Whistler (Jessica Biel) fires an arrow loaded with the virus at him from behind. Unfortunately, Drake turns around in time and catches the arrow in midair, but Blade manages to get the arrow and stabs Drake with it. The virus kills all the vampires. Before Drake dies, he tells Blade that he (Blade) will be the start of a new generation of vampires, and that Blade's vampire nature will eventually win out over his human side. As the sun rises, the dead vampires turn to ash. We are made to think that Blade has been killed by the virus, but when his body being autopsied, it suddenly c hanges into the body of Drake (who is a shape-shifter). As we see Blade riding off on his motorcycle, a voice-over from Hannibal King (Ryan Reynolds) explains that Blade is still out there, "doing what he does".
Thanks, Alena B!