Many beds are empty at newly opened Ebola treatment units in Liberia's urban centers because the outbreak is now flaring in more rural parts of the country. In Sierra Leone's capital, there aren't enough treatment units as the epidemic spreads there, AP reported. Those helping battle the world's worst Ebola outbreak must be more agile to catch up as the dreaded disease jumps from one place to another, experts say. That's a challenge because it is a slow process for governments to authorize aid, to gather it together and then deliver it. And to build treatment units, even rudimentary ones, takes even more time. By the time they're built, the outbreak may have moved elsewhere. In Liberia, the U.S. this week opened an Ebola treatment unit in Tubmanburg, about 40 miles (64 kilometers) north of the capital, Monrovia. A 250-bed Doctors Without Borders clinic in Monrovia is treating only about 50 patients. There have been no patients at another facility in Foya, in northern Liberia, since Oct. 30. The U.S. plans to build 17 units in all, and it has already opened a field hospital to treat infected health workers. The head of the U.N. mission fighting Ebola in West Africa called on Thursday for a more flexible and nimble response that puts treatment units in remote regions and gets staff rapidly to new outbreaks. -- SPA 19:52 LOCAL TIME 16:52 GMT تغريد