Mystery virus identified
The mystery virus has been provisionally identified as an arenavirus.
The virus is rodent-borne and related to the Lassa fever virus of West Africa, according to the National Institute for Communicable Diseases and the Department of Health.
Arenaviruses cause chronic infections in multimammate mice — a kind of wild mouse — who excrete the virus in their urine which can then contaminate human food or house dust. Viruses similar to the Lassa fever virus has been found in rodents in Africa, but other than in West Africa have not been found to cause diseases in humans.
However, Lucille Blumberg of the NICD says that there is no evidence that the virus is present in South African rodents.