Look, The Fifth Wave is a fun read, and nobody enjoys a good alien invasion of Earth yarn more than me, though living on Mars as I've been doing for the past two Earth years gives me an interesting perspective on this subgenre. I mean, c'mon Mr. Wells, did you really think Martians would be too dumb to remember to get their shots before invading the Earth? Sheesh, even the late unlamented Johnny Marshall alias "King Ares III" wouldn't have been that stupid.
This, unfortunately, is not much of a digression from my review, because Mr. Yancey's novel indulges in the plague theme along with a bunch of other superannuated tricks (although it's the aliens who turn nasty little critters loose on us humans). That's not giving away much, because the first four "waves" of the alien assault are neatly listed at the beginning of the novel, and the first three won't cause any science fiction fan worth her salt to so much as raise a purty little eyebrow, though they are said to have done in about 99 percent of Earth's human population: "Lights Out," (i.e., your friendly neighborhood Cold War bogeyman, the Electromagnetic Pulse famed of song, story, and fried circuitry of all kinds); "Surf's Up" (worldwide tsunamis caused by the simple expedient of dropping junk into active undersea faults); and the aforementioned plague, pneumonic Ebola virus (all right, that one was scary if not very original). It doesn't take long for the cryptic "Silencer" fourth wave listed helpfully at the start of the book to reveal itself as a good old-fashioned Invasion of the Body Snatchers. So, what is the eponymous Fifth Wave?
*************SPOILER ALERT*************The Fifth Wave is a children's crusade, orchestrated by the Body Snatchers, who cleverly tell the young pups that they are exterminating the invaders when they're really being used to hunt down all surviving adults who haven't been Body Snatched. But, not to fear, one of the Snatchees is about to turn traitor on his own alien folk... and all for love of a sixteen-year-old girl, our heroine, Cassie-short-for-Cassiopeia.
Pardon me while I puke all over this plot device. But we've got bigger problems, pardner. Any writer worth his salt, in fact any reasonably sentient person, knows that despite or perhaps because of their vaunted life experience, adults can be way easier to trick than kids, who have yet to be fully trained in the intuition suppression known as "acting civilized." So I would think the Body Snatchers would be more likely to run their three-card monte scam on the surviving adults. Still, there is a genuine creepiness to the idea of brainwashed child soldiers, which has in fact cropped up all too frequently in the so-called real world ("Lord's Resistance Army," anyone?)
So my major complaint with the novel is that we do not get nearly enough of the Children's Crusade and its implications, and what we do get is largely focused on teenage draftees when a first-person account from a seven-year-old (the lower age limit for the Crusaders, we are told) would be much more compelling, if harder to write. Also, there is a planet-sized plot hole in that we are told the invaders are disembodied consciousnesses (that's how they can Body Snatch, natch) with no apparent plans to reincarnate themselves--the Snatching of what they regard as repulsive human bodies being an unfortunate exigency of war, in their view. In that case, WHAT IN TARNATION DO THEY NEED THE EARTH FOR? I'm talkin' to you, Mr. Yancey!