Read this in the context of the current political environment.
They buzz all around, but you rarely see the one that gets you.
The swamp is a perfect place for them to live, and grow, and reproduce.
Individually, they are mostly benign, but there are those that carry something that will really get you.
They get “into your head”, and, even if they are not biting this very minute, you stay fully aware they are still there.
They are out for blood.
Just one more reason to drain the swamp!