A lot of "Vampire" folklore get's lumped in together with the most popular depiction even if they only bear vague similarities. Also Dragons are common stand-ins for Satan, so there's a cursed by God angle baked in. On Coppola's film, I forget where I got this from, but it was apparently the originator for a romance between Mina and Dracula, which influenced the direction Vampire fiction went after, at least on film.
Except that the nickname Dracul came from his membership of the Order of the Dragon, a knighly order dedicated to St. George which focused on opposing the Ottoman Empire (= the dragon they wanted to slay).
