More links to this story.
One of the doctors said that the disease that Travis had, which is called Lyme disease is related to rage and depression, which do also happens on humans... so it could be why he "snapped" all of a sudden.
Residents Shocked By Brutal Chimp Attack - Connecticut News Story - WFSB Hartford
'Shoot him!' Chimp owner heard on 911 call - Life- msnbc.com
Travis is alot bigger than I thought. 
close to the size of a silverback goriall. No wonder he was so difficult to handle when he attacked these women.
