The discovery of active, transmittable Marburg virus in fruit bats caught in three Sierra Leone locations marks the first time the virus has been found in West Africa and has identified a potential public health threat without a single known case of human illness, the U.S. Centers for Disease Control announced today.
The Marburg virus, often called a “close cousin” to the Ebola virus, was first identified in Germany when laboratory workers carrying out research on imported African green monkeys in Marburg and Frankfurt, Germany as well as in what was then Yugoslavia, fell ill with hemorrhagic fever, their illnesses spreading to family members and health workers who cared for them. Seven of at least 31 people infected during that outbreak died. Twelve outbreaks of the disease — in Uganda, Zimbabwe, the Democratic Republic of Congo, Kenya, Angola and South Africa — apparently sparked by mine-workers’ exposure to fruit bats and then transmitted, as Ebola has been, to care givers, and through funeral practices, have been confirmed over the years since. The largest known outbreak occurred in Angola, where 90 percent of 252 people infected died.
The discoveries of five Egyptian rousette bats carrying the Marburg virus in Sierra Leone were made through projects supported by the U.S. Centers for Disease Control and Prevention in partnership with Njala University and USAID in partnership with The University of California Davis and the University of Makeni, launched in the wake of the 2013-2016 Ebola outbreak in West Africa to find locations of bats harboring that disease. Diversity among the strains of Marburg virus found indicates that the virus is not new to bat colonies in Sierra Leone, the CDC noted. While bats do not get sick from the virus, the presence of the virus has typically been discovered when humans, exposed through fruit contaminated by bat droppings or saliva, through bat bites or through other animals infected by exposure to the bats, fall ill.