Filoviruses is amongst the most lethal of primate pathogens. Filoviruses cause lethal hemorrhagic fever in humans and nonhuman primates. The family Filoviridae includes two genera: Marburgvirus, comprising various strains of the Lake Victoria marburgvirus (MARV); and Ebolavirus (EBOVs), comprising four species including Sudan ebolavirus (SEBOV), Zaire ebolavirus (ZEBOV), Ivory Coast ebolavirus (CIEBOV), and Reston ebolavirus (REBOV); and a tentative species Bundibugyo ebolavirus (BEBOV).

The infections typically affect multiple organs in the body and are often accompanied by hemorrhage (bleeding). Once the virus has been transmitted from an animal host to a human, it can then spread through person-to-person contact.