The Ebola outbreak that was called "unprecedented" when it had killed 80 people in March has now infected at least 500 people in three countries and health authorities say they're not sure how to stop it. The outbreak has now killed at least 337 people, making it the worst since the incurable virus surfaced in 1976, and reported cases have surged 60% over the last two weeks. "There are many villages in the eastern part of Sierra Leone that are basically devastated," a virologist tells NPR. "We walked into one village ... and we found 25 corpses. One house with seven people, all in one family, were dead."
Experts say the virus tends to kill so quickly that outbreaks are relatively easy to stop, but this outbreak, the first major one in West Africa, is different, with the virus spreading from Guinea into Sierra Leone and Liberia. "This is a complex outbreak involving multiple locations in three countries with a lot of cross-border movement among the communities," a UN health agency spokeswoman tells Al Jazeera. "This makes this one of the most challenging Ebola outbreaks ever." She says fear of the disease has hampered efforts to isolate infected people and more needs to be done to get sick people into treatment and track down people they have come into contact with. A few days ago, the first cases surfaced in the Liberian capital, including at least seven deaths, the AP reports. At a hospital on the outskirts of Monrovia, staff and patients fled after the death of a nurse. (Read more Ebola stories.)