That's an interesting anti-vampiric plot device.

[modernwizard]

Over on Moonlight, previously mentioned here, season 1, ep. 12, The Mortal Cure, summarized here,  El Doofus Grande, Mick, learns about a temporary antidote to vampirism. Developed during the French Revolution [?!], this herbal compound temporarily makes a vampire mortal if absorbed through an open wound. That's a neat plot device: temporary mortality. Too bad I didn't think of it.

Overall, Moonlight alternates between pissing me off and entertaining me. The overdetermined and shallow narration adds nothing and detracts a lot from the story. The characters aren't particularly deep. At the same time, the creators seem to have invested actual brainpower into vampires not only as supernaturals, but also as members of a subculture with its own hierarchy and rules.