Rwanda's first outbreak of viral hemorrhagic fever was detected in late September, with 46 cases and 12 deaths reported since then

Marburg has caused small, episodic outbreaks since first being identified, most recently last year in Tanzania and Ghana. It is one of the deadliest known viruses, with no approved vaccines or specific treatments.

The East African country continues to investigate the source of the outbreak, first traced among patients in health facilities.