Construction workers build an Ebola isolation and treatment center in front of a unfinished and abandoned government building in Monrovia, Liberia, Thursday Sept. 25, 2014. The center , due to open within two weeks, will add 200 beds to existing centers. The outbreak of Ebola has overwhelmed the weak health systems of some of the world's poorest countries: There aren't enough doctors and nurses or even clinics to treat the spiraling number of cases.(AP Photo/Jerome Delay)

(AP)—The World Health Organization says the number of deaths linked to an Ebola outbreak in West Africa has passed 3,000.

The new tolls published Friday showed that there were more than 150 deaths in Liberia alone in just two days. The outbreak has also touched Guinea, Sierra Leone, Nigeria and Senegal—but it is the worst in Liberia.

WHO has said that even the heavy toll in this outbreak—the largest ever—may be an underestimate. Cases are going unrecorded because people are afraid to go to hospitals, or, worse, are turned away from them because they're overflowing.

The latest figures said more than 6,500 people are believed to have contracted Ebola.

Construction workers build an Ebola isolation and treatment center in front of an unfinished and abandoned government building in Monrovia, Liberia, Thursday Sept. 25, 2014. The center , due to open within two weeks, will add 200 beds to existing centers. The outbreak of Ebola has overwhelmed the weak health systems of some of the world's poorest countries: There aren't enough doctors and nurses or even clinics to treat the spiraling number of cases. (AP Photo/Jerome Delay)

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