AlQa'dah 2, 1435, Aug 28, 2014, SPA -- The Ebola outbreak in West Africa could eventually reach 20,000 cases, more than six times as many as are now known, the World Health Organization (WHO) said Thursday. A new plan by the U.N. health agency to stop Ebola also says that the actual number of cases in many hard-hit areas may be two to four times higher than currently reported. If that is accurate, it suggests that there could be up to 12,000 cases already. "This far outstrips any historic Ebola outbreak in numbers" Dr. Bruce Aylward, WHO assistant director-general for emergency operations, told reporters. "The largest outbreak in the past was about 400 cases." "What we are seeing today, in contrast to previous Ebola outbreaks is multiple hotspots within these countries not a single, remote forested area, the kind of environments that have been tackled in the past, and then not multiple hotspots within one country, but international disease," Aylward said. Aylward said that another new dimension is the difficulty in dealing with Ebola in large cities and broad areas. The agency published new figures saying that 1,552 people have died from the virus from among the 3,069 cases reported so far in Liberia, Sierra Leone, Guinea, and Nigeria. At least 40 percent of the cases have been identified in the last three weeks, WHO said, adding that "the outbreak continues to accelerate." WHO released a new plan for handling that aims to stop Ebola transmission in affected countries within six to nine months and prevent it from spreading internationally. The plan calls for $489 million to be spent over the next nine months and requires 750 international workers and 12,000 national workers.