United Nations, Shawwal 19, 1436, Aug 4, 2015, SPA -- The World Health Organization (WHO) said Tuesday that Guinea and Sierra Leone each reported a single case of Ebola in the past week. WHO Assistant-Director Bruce Aylward told reporters that tight surveillance and tracing contacts of infected people remain crucial, and are especially challenging during the heavy rains in August. "The progress is real ... as of today we have two cases (in the week to August 2)," Aylward said. "It is a realistic goal to have transmission stopped this year." According to the WHO, in the previous week to July 26, there were seven confirmed cases in the two countries, which had been the lowest in the past year. More than 11,000 people in West Africa have died during the epidemic since December 2013. --SPA 20:45 LOCAL TIME 17:45 GMT www.spa.gov.sa/w