Human cases of 'highly fatal' Marburg virus recorded in Africa, CDC warns

April 6 (UPI) -- Cases of the "highly fatal" Marburg virus disease, which can have a mortality rate of between 23% and 90%, have been recorded in two African nations, the Centers for Disease Control and Prevention warned Thursday.

"Marburg virus disease is a rare but highly fatal viral hemorrhagic fever caused by two zoonotic viruses, Marburg virus and Ravn virus, that are closely related to ebolaviruses within family Filoviridae," the CDC said in the health advisory.

The disease is not contagious until symptoms appear, which can include fever, headache, fatigue, muscle and joint pain, loss of appetite and unexplained bleeding. It is spread through contact with the blood or body fluids of an infected person. It is not spread through airborne transmission.

CDC officials said that one case was recorded in the Central African nation of Equatorial Guinea in February while another was recorded in the East African nation of Tanzania in March.

No cases have been reported in the United States or any other country, though officials warned that there is currently no vaccine or treatment approved by the Food and Drug Administration.

"These outbreaks mark the first time that Marburg virus has been identified in either Equatorial Guinea or Tanzania, though the virus has been identified previously in neighboring countries and the reservoir, the Egyptian fruit bat, is known to be present in both countries," the advisory reads.

Officials said that early information suggests that the two cases are believed to have originated in their respective countries with no evidence suggesting that the outbreaks are linked. Experts are currently conducting viral genetic sequencing on the samples from the Tanzania case to compare with Equatorial Guinea.

Health officials in Equatorial Guinea said that the first case came after a "cluster of deaths" from a viral hemorrhagic fever were reported in two villages in the district of Nsok-Nsomo in February. Samples were collected from each of those who died and one was confirmed to have tested positive for the virus.

That patient had presented with fever, vomiting, bloody diarrhea, and convulsions and died the same day, according to the CDC.

"This patient appears to be epidemiologically linked to four deceased community members from one of the affected villages in NsokNsomo district," the advisory reads.

A CDC-supported laboratory at a local hospital confirmed Wednesday that 14 cases have been identified in the county and that 10 of those cases have been fatal.

"There are no known epidemiologic links between patients in one province, Centre Sur," the advisory reads.

"This, taken together with the wide geographic spread of the outbreak within the country, suggests that there may be undetected community spread of the virus in the country."

While the risk of MVD in the United States remains low, the CDC said that clinicians "should be aware of the potential of imported cases."

The last reported outbreak of MVD occurred in Ghana's Ashanti region in 2022, with three cases and two deaths recorded.