Vampire bats, that is. Still, great cover. Stories and flicks centred around mass vampire bat attacks aren't unique. There's Martin Cruz Smith's novel, Nightwing (1977), it's cinematic adaptation (1979) and, of course, Vampire bats (2005).
But their path of destruction's paled—and preceded—by the apocalyptic vampire bats in Alan Hyder's novel, Vampires overhead (1935). Oh, and they're also from outer space.