A Nigerian health official wearing a protective suit waits to screen passengers at the arrivals hall of Murtala Muhammed International Airport in Lagos, Nigeria, Monday, Aug. 4, 2014. Nigerian authorities on Monday confirmed a second case of Ebola in Africa’s most populous country, an alarming setback as officials across the region battle to stop the spread of a disease that has killed more than 700 people. (AP Photo/Sunday Alamba)