Kasokero virus

As a typical member of the Nairoviridae family, Kasokero virus is a negative sense, single-stranded RNA virus with a genome divided into three segments: large (encoding the RNA dependent RNA polymerase), medium (encoding glycoproteins Gn and Gc) and small (encoding the nucleocapsid protein).^[4]

Kasokero virus was first isolated from serum samples collected from Egyptian fruit bats, known natural reservoirs of the human-pathogenic Marburg virus (Orthomarburgvirus marburgense).^[3] In addition, the virus has also been isolated from soft argasid ticks (Ornithodorus faini), observed to feed on fruit bats and considered part of the enzootic transmission cycle of Kasokero virus.^[3]

To date, Egyptian fruit bats are the only known vertebrate hots of Kasokero virus on the African continent. Ecological surveys of wild-caught bats in Uganda have detected that, on average, about 3% of these bats are positive for Kasokero RNA.^[5] Experimental infections of Egyptian fruit bats with Kasokero virus have shown that infected bats don't develop overt signs of disease despite detectable virus replication in various tissues.^[6][7]

Shortly after its discovery in 1977, Kasokero virus caused laboratory-acquired infections among three laboratory staff members at the Uganda Virus Research Institute. A fourth case was later also detected in a driver who had reported no direct contact with lab staff or facilities.^[8] Among the four cases, clinical signs of disease ranged from mild febrile illness to prolonged systemic disease involving fever, headaches, arthralgia, stomach pain, nausea, diarrhoea, chest pain and coughing.^[3]