A New Jersey man died Monday evening after been diagnosed with Lassa fever - a frightening infectious disease from West Africa that is rarely seen in the United States, a federal health official said. The man recently returned from Liberia, arriving at New York City's JFK International Airport on May 17. He grew critically ill after his return, suffering from multiple organ failure, said Dr. Tom Frieden, director of the U.S. Centers for Disease Control and Prevention in Atlanta.