Just a couple of addenda to my post on The Swarm:
I found this page that offers a comparison of The Swarm and the novel it's ostensibly based on, by Arthur Herzog. Short version: the movie has very little to do with the novel, which is a "slightly above average pop novel." The one scene in the movie that sort of works, the scene where an immunologist tests his vaccine on himself, is from the novel.
But I should also note that Herzog's bio actually boasts about the fact that he wrote the source material for the movie versions of not only The Swarm but also Orca. I would think that'd be something he'd want hushed up.
And (from Badmovies.org), here's the moment when The Swarm truly established itself as a masterpiece of badness. It's amazing how much bad dialogue, bad special effects, bad line delivery, bad acting from good actors (Caine and Widmark) and total outer-space logic can be packed into 30 seconds of film.