Jaws screen reading software does not change the keyboard navigation and as such user cannot access any of the menus in JIRA Agile. There are some hotkeys but not for all features

Specific to the scrum boards user have to navigate with the keyboard top to bottom left to right. This means that to be able to read the description of an item in the scrum board, the user have to first read the entire backlog start to finish. Then to go to the next item have to keyboard navigate back to where was and repeat the process. This means hundreds of keystrokes to accomplish the task of reading the description of one item.

Referral links:
Jaws screen reader: http://www.freedomscientific.com/products/fs/jaws-product-page.asp
Accessibility Standards: http://en.wikipedia.org/wiki/Web_Content_Accessibility_Guidelines