They slither and squirm. They're slimy and can be deadly. Parasites are the hidden invaders of our bodies. But studying these body snatchers can be, well, disgusting. Imagine a brain-eating amoeba that swims up your nose or a sneaky parasite that kills its host's tongue--and then becomes its new tongue! Featuring the latest scientific research, this humorous hi-lo book dives into the gross and weird world of parasites.