Snakes on a Train 2006 ( 3.7)

Under a powerful Mayan curse, snakes are hatched inside a young woman, slowly devouring her from within. Her only chance for survival is a powerful shaman who lives across the border. With only hours to live, she jumps on a train headed for Los Angeles. Unfortunately for the passengers aboard, they are now trapped, soon to be victims of these flesh-eating vipers.