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

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.

Health officials in Rwanda are dealing with the country’s first outbreak of the Marburg virus, an Ebola-like disease which, if left untreated, has a fatality rate of up to 88%.