Thomas Nellon, left, 17, and his brother Johnson Nellon, 14, of Liberia, smile at their mother in the arrivals area at John F. Kennedy International Airport in New York, earlier this month. The brothers received a health screening upon arrival. The U.S. says it will step up screening measures for arrivals from Ebola-affected West African countries. Craig Ruttle/AP hide caption

itoggle caption Craig Ruttle/AP

Hong Kong Federation of Students council members attend a meeting with senior Hong Kong government officials in Hong Kong on Tuesday. Tyrone Siu/Reuters/Landov hide caption

itoggle caption Tyrone Siu/Reuters/Landov

Swedish corvette HMS Stockholm patrols Jungfrufjarden in the Stockholm archipelago, Sweden, on Monday. Swedish authorities say they've detected "foreign underwater activity" thought to be a possible Russian submarine. Anders Wiklund/EPA/Landov hide caption

itoggle caption Anders Wiklund/EPA/Landov

Pro-democracy protesters gather during a rally of the ongoing Occupy Central movement in the Admiralty District of Hong Kong on Monday. The territory's leader has accused foreign elements of helping stoke unrest. Jeon Heon-kyun/EPA/Landov hide caption

itoggle caption Jeon Heon-kyun/EPA/Landov

Dutch Foreign Minister Bert Koenders (center) speaks with Luxembourg Foreign Minister Jean Asselborn (second from left) and British Foreign Minister Philip Hammond (right) during a round table meeting of EU foreign ministers in Luxembourg on Monday. The ministers hope to raise 1 billion euros to fight Ebola. Virginia Mayo/AP hide caption

itoggle caption Virginia Mayo/AP