Recovering in hospital after he was mauled by a large shark, David Pearson spent 12 hours reacting to another kind of vicious assault - comments on social media by people who wished he had died. They said Pearson didn't deserve sympathy because Australia was a "shark nation".

"Here's me sitting in hospital, thinking, 'What have I done to these people?' I have done nothing but get bitten by a shark, and all of sudden, I was the worst person in the world," Mr Pearson said. In 2011, a three-metre long bull shark bit his left arm while he was surfing at Headland Beach on the Mid North Coast.

David Pearson set up Bite Club to help other victims of shark bites. Credit:James Brickwood

Now new research by the University of Sydney’s Brain and Mind Centre shows shark-bite survivors who were attacked in the media were 12 times more likely to say they had symptoms of post-traumatic stress disorder (PTSD) than others who had been attacked.

Published in the Australian and New Zealand Journal of Psychiatry on Wednesday, the study surveyed 60 Australian shark-bite survivors, witnesses, first-responders, and their families. They were all members of a group called Bite Club, which Mr Pearson established in 2012 to help survivors recover and cope with media attention.