MELBOURNE, AUSTRALIA (REUTERS) - All Sam Kanizay did was cool his feet off in the water at Dendy Beach in Melbourne, Australia. By the time he'd hobbled home it was a bloodbath. "By the time I had walked across the sand, about 20m, to put my thongs on, I looked down and noticed that I had blood all over my ankles," said the 16-year-old. Thousands of tiny bites were found all over Sam's feet, baffling doctors and nurses at first.