According to the Post-Dispatch Fowler does have the flu along with the rest of his family. He’s being given fluids because he was apparently getting dehydrated.
I agree that JMart’s defense is passable. But that’s mainly because his hitting keeps people from thinking so much about his mistakes in the field. He looks really clumsy at times in the field. If his manager and coaches had sent him up to the Royals, and if he then would have made one of his clumsy mistakes, the manager and coaches would have had to dodge some rotten apples.