Services worker Marcelo Rocha Santos, 51, left work last Saturday and met up with a group of friends at Piedade beach in Greater Recife, one of the largest cities in Brazil’s Northeast. After a game of football in the sand, he took a quick dip in the sea to wash himself off. As he waded back to shore, Mr. Santos appeared panicked and screamed for help.
The water was at waist height when Mr. Santos’s friends arrived to rescue him, and as they got closer they noticed a large pool of blood gathering around his legs. He had severe...