Well, we all know about shark shields, but a guy in Florida is focusing on more passive materials that may be a bit more applicable for fishing, such as shark repellant hooks. Whether it it will work or be incorporated into fishing gear remains to be seen. Could just be a load of bunk and not work, but interesting if theres something you could add to hooks. No mention of shark shields in the article though which is odd.

http://www.bbc.co.uk/news/magazine-17792624