The flare-up is due to a number of factors including people going in and out of Liberia and traditional practices such as the washing of bodies, said Liberia's Assistant Health Minister Tolbert Nyenswah.
Forty-nine cases were reported in in western Grand Cape Mount County between December 1 and 25, Nyenswah told state radio.
"In a very small population, an increase in the number of (Ebola) cases raises high level of concerns that we need to take very seriously as people of Liberia and people of Grand Cape Mount in particular," he said.
Sierra Leone, in comparison, has now eclipsed Liberia with more than 9,000 Ebola cases, according to the World Health Organisation.
