On 29 June 2015, a new case of Ebola virus disease was identified in Liberia 50 days after interruption of active transmission was achieved on 9 May. Since then, a cluster of cases has been identified, all of them from Nedowein in Margibi county. Currently, 5 people have been confirmed with Ebola virus disease by laboratory testing.
As part of the investigation into the source of this new cluster of infections, samples taken from the first person found to have Ebola were sent to the Liberian National Reference Laboratory for genetic sequencing. Tests on these samples have shown that the virus is genetically similar to viruses that infected many people in Margibi County more than 6 months ago, in late 2014.
This information provides important insights into the probable origin of the virus responsible for this new flare in Liberia. Because the virus appears to be related to the one previously circulating in Liberia, it is unlikely that this recurrence has been caused by virus imported from infected areas of Guinea or Sierra Leone. It also makes it unlikely that this has been caused by a new emergence from a natural reservoir, such as a bat or other animal.
Genetic sequencing on samples from the 4 other cases in this new outbreak is underway.