We now know that exposure to brief sunlight while soaked in water can somehow cure a vampire.

It's true that vampires will bake if exposed to sunlight for too long ,but if a vampires blood was somehow

heated by the sun's rays while inside the body, their heart would start beating again.This treated blood

thus turns into a Human vaccine of sorts, this also prevents those cured from being turned into vampires

ever again ,making this the perfect defense in the war to rebuild the human race.