I think that both this and the daywalker stuff come next to exclusively from the movie Blade, which wasn't a particularly traditional view on vampires, or something close to it. I tried some searching to find any references...vampire with anything like "silver kills" reveals nothing classical, although I might have missed some combination (just silver gives to many false hits to cut down). Definitely daywalker got nothing other than RPGs and movies. Neither of these are listed on Britannica's page or any of the kid's books I can remember.
I found an interesting article on themestream.com [[1]]
I believe that the silver as dangerous to vampires theory has basis in history. --Alan D
Bram Stoker introduced us to "undead," of course, contemporaneously with the modernized legend of Vlad Drakul - aka "Vlad the Impaler" who was a quite real old-time prince who terrorized local peasants by hanging the heads and bodies of those who displeased him from stakes outside the "castle" or manor house.
Silver bullets are supposed to kill werewolves. Until a movie was made on the subject, I wonder if there was any substantial literary classic involving lycanthropy (people turning into wolves) to which we can refer, or if oral tradition is all there is to fall back on. Oral tradition does go back hundreds of years, at least.
I think there's some instances of lycanthropy amongst the ancient Greeks. There should be a book on my shelves somewhere with a detailed history of this sort of thing...
Getting back to vampires, it's interesting to see how Bram Stoker's Dracula was an assortment of folk traditions, grafted onto a more or less Roman Catholic framework of demonic possession; his Dracula is effectively the corpse of Vlad Dracul possessed by a demon - hence the crucifix & holy water being so effective.
How about mentioning vampire legends which do *not* depend so heavily on Stoker's work? e.g. works by Anne Rice, and, um, well that's all I can think of. :-) I haven't read up on vampires much, which was why I followed this link. :-)