Jojo If the book was Host, then it would have the same idea and be called Host. Yes, the book is about aliens, but it is also about other things as well. The 5th wave drove me crazy when I finished because I wanted more. And told, everything is not always what it seems. Read it and you will find out it is very different then Host. When I read it, Host did not pop into my head, like some books can relate to others this one I couldn't really think of anything. Please read it. Great read.
This answer contains spoilers… (view spoiler)[No, in this book they don't take over bodies that way. They want to kill all. If they are in a human body it's because they came down years and years before, and 'downloaded' themselves into a baby within a womb, sleeping until the moment they were awoken, after the baby has grown up. (hide spoiler)]