Scientists have found the deadly Marburg virus in one type of African fruit bat, the first time it has been detected in an animal other than a monkey.
The bats were collected in the West Africa countries of Gabon and the Republic of Congo, but the test results support a theory that bats caused two recent Marburg cases in nearby Uganda, health officials said.
Scientists are not sure how Marburg is transmitted to humans, but for years they have suspected bats have something to do with it.
"It's a big step in pointing us in the right direction," said Jonathan Towner, a US Centers for Disease Control and Prevention (CDC) microbiologist investigating the Uganda outbreak.
Towner is also coauthor of the paper containing the tests results from Gabon and the Republic of Congo. The paper appears in PLoS ONE, an online medical journal.
Two dozen investigators from the CDC, the WHO and other health agencies have been in a remote part of western Uganda, following the death last month of a 29-year-old man who worked in a lead mine there.
The man died of Marburg virus, a rare cousin of Ebola that can cause a rapid and gruesome death in which patients may bleed from the eyes, ears and elsewhere. A second miner is also believed to be a Marburg case.
Since Marburg was first identified in 1967, large outbreaks have been reported in Congo, Angola and other countries. It can spread from person to person and international health responses to outbreaks are common.
"It's very scary," said James Steinberg, a professor of infectious diseases at Emory University's School of Medicine.
In the new paper, scientists say they tested more than 1,100 bats representing 10 species. They found Marburg in only one species, Rousettus aegyptiacus, a common type of fruit bat that lives in caves. Four bats tested positive for the virus, and 21 tested positive for at least low levels of antibodies to the virus, Towner said.