He can see the consideration in that frown, knows what she's about to try, and feels a great deal of relief when she decides against it.

"All right. Could you use anything else? Because you are here and I truly would like to help." Even if she doesn't know of anything non-magical that could have caused this. He doesn't know how to spin this if people start worrying about magical diseases on top of everything else in regard to mages, but he's going to have to figure it out.