I found this quote interesting for two reasons. The first is that something can be that small, and if you read on that there are things that can be even smaller than that. It's amazing how very little things can be and if you, say, took a microscope to the skin under your fingernail (according to XKCD, you should never do this), you'd probably find all sorts of insane viruses and bacteria lurking around in there just waiting to kill you.
The other reason was because I get sick so often. I thought it was interesting that the thing which potentially made me sick was smaller than what I could see, perhaps even imagine, and yet it did so much damage. It's amazing to think that something so small could cause such a large reaction... and if that's true, then maybe the theories about even smaller things manipulating the universe may have some credibility to them...