Commuters ride an L train for the morning commute a day after an announcement that the subway system had been used by a doctor now testing positive for Ebola in New York October 24, 2014. Craig Spencer, a New York City doctor who treated Ebola patients in West Africa, became the first person to test positive for the virus in America's largest city, setting off fresh fears about the spread of the disease. New York Mayor Bill de Blasio said residents were safe to travel around the city, even as officials disclosed that Spencer had ridden subways, taken a taxi and visited a bowling alley since returning from Guinea on October 17. REUTERS/Lucas Jackson (UNITED STATES - Tags: HEALTH DISASTER TRANSPORT)