The Japanese giant oyster has created problems for bathers on the West Coast. A number of people have had to seek medical care after being injured by the oysters.
One of them is Andreas Rosenqvist. During a swim on his last day of vacation, he stepped right on an oyster and got a seven-centimeter jack. The injury gave him strep and canker fever and Andreas had to spend four weeks in hospital. Now he wants to warn others.
Hear Andreas tell more in the player above.