A medical relief worker at an Ebola treatment center in Guinea says new patients continue to be admitted on a daily basis.
Jonas Hagensen, of Doctors Without Borders, says many of the people receiving treatment at the center in Conakry know how they were exposed.
"A lot of the people who come into our centers, they actually know how they had been infected because they had been in close contact with a person that they know had had Ebola."
In a VOA interview, Hagensen said medical relief workers are concerned about people who may be showing symptoms of the deadly virus but are not receiving treatment.
"The concern is that the people who are sick, they actually get into the treatment center and that we make sure that we have all of their contacts. That is the difficult part, to get people who believe that they are sick and they know that they had contact with someone who had Ebola, that we can get the whole picture of all those people who had been in contact with that person. It is a huge, huge work and it is very, very demanding."
At least 142 deaths from Ebola have been reported in Guinea and Liberia since the outbreak erupted in the region in February. Health officials are also investigating confirmed or suspected cases in Guinea, Liberia and Sierra Leone.
The Ebola virus is spread by contact with bodily fluids. It causes symptoms that include vomiting, unstoppable bleeding and organ failure.