Washington, Shawwal 4, 1435, Jul 31, 2014, SPA -- U.S. health officials on Thursday issued an advisory against non-essential travel to Guinea, Liberia, and Sierra Leone in an effort to limit the spread of the Ebola outbreak in West Africa that so far has claimed more than 700 lives. The U.S. Centers for Disease Control and Prevention (CDC) said the risk of the deadly disease coming to the United States remains small, but the last time the federal agency issued such a travel warning was in 2003 due to the SARS (severe acute respiratory syndrome) outbreak in Asia. Doctor Thomas Frieden, the CDC director, said his agency is intensifying its response to the outbreak and will send an additional 50 health experts to assist with efforts to control the outbreak. At the White House, spokesman Josh Earnest said Washington is looking into medical-evacuation options to bring home two U.S. aid workers diagnosed with Ebola. A senior State Department official said the spread of the deadly virus and assistance for affected countries will be discussed during an African summit in Washington next week. U.S. Assistant Secretary of State for Africa Linda Thomas-Greenfield said the issue will be discussed in detail during side meetings. --SPA 21:33 LOCAL TIME 18:33 GMT www.spa.gov.sa/w