A species of African fruit bat may be the long-sought natural host of the deadly Marburg virus, according to a study published this week.
The animal sustaining Marburg transmission has been difficult to find because outbreaks of the virus often take place in tropical settings teeming with different animals and insects.
Jonathan Towner, a microbiologist with the federal Centers for Disease Control and Prevention, said the bat, Rousettus aegyptiacus, was a good suspect because it roosts in caves.
"It fits very nicely with the epidemiological data of previous outbreaks, where it has been linked back to caves and mines," said Towner, lead author of the study, published Wednesday in the journal Public Library of Science One.
Bats also have been found to carry Ebola, a virus related to Marburg. Like Ebola, Marburg causes hemorrhagic fever, with symptoms including diarrhea, rash and gastrointestinal hemorrhage.
Marburg virus was first recognized in 1967 after outbreaks in Marburg, Germany, and two other European cities when laboratory workers handled sick monkeys from Uganda.
Nearly 450 people have contracted the disease worldwide. More than 80% have died.
One of the largest outbreaks, in the Democratic Republic of Congo, involved mostly young miners.
Two cases have been tracked to a cave in Kenya.
Towner's group tested more than 1,100 bats representing 10 species from five locations in Gabon and the Republic of Congo.
Only R. aegyptiacus tested positive, with four bats showing low levels of the virus in their tissues and five showing significant levels of Marburg antibody in their blood.
The study is the first to show the Marburg virus in anything other than a human or primate.
"We still haven't found a definitive reservoir for Marburg virus, but this is the best lead we have," said Dr. C.J. Peters, a virology researcher at the University of Texas Medical Branch in Galveston, who was not involved in the study.