[Barriss being a Jedi is something Leia doesn't know and can't particularly tell solely by looking at her. And as it is, many of the Jedi teachings are something Leia herself doesn't know. She may have trained slightly with the Force here, but she trained with the explicit request that she not be considered a Jedi.

Her gaze once again falls to Barriss' stone foot. She's not fully sure which emotion would be causing that, but centering herself is bound to help, Leia knows that much. And while she maybe can't make Barriss calm down, she can continue to try and help as best she can.]

I wouldn't consider it a disease, but yes. It's a tall order to ask you to calm down upon arriving in a place like this, I know.

[She pauses, before continuing, thinking over both their current surroundings and the emotions in effect here.]

Perhaps moving to a less populated area might help. Do you think you can walk?