Because there is a close relationship between Marburg and Ebola, the scientists are also hopeful that progress on one virus could help solve the puzzle of the other.
By day, some of the most dangerous animals in the world lurk deep inside this cave. Come night, the tiny fruit bats whoosh out, tens of thousands of them at a time, filling the air with their high-pitched chirping before disappearing into the black sky.
The bats carry the deadly Marburg virus, as fearsome and mysterious as its cousin Ebola. Scientists know that the virus starts in these animals, and they know that when it spreads to humans it is lethal — Marburg kills up to 9 in 10 of its victims, sometimes within a week. But they don’t know much about what happens in between.
That’s where the bats come in. No one is sure where they go each night. So a team of scientists from the U.S. Centers for Disease Control and Prevention traveled here (Uganda) to track their movements in the hopes that spying on their nightly escapades could help prevent the spread of one of the world’s most dreaded diseases. Because there is a close relationship between Marburg and Ebola, the scientists are also hopeful that progress on one virus could help solve the puzzle of the other.
Their task is to glue tiny GPS trackers on the backs of 20 bats so they can follow their movements.
“We want to know where they’re going on a nightly basis,” said Jonathan Towner, 52, who heads a CDC team that specializes in how these deadly viruses are spread. If the animals are feeding on particular fruit trees, that information could identify communities most at risk and help prevent future outbreaks. “It’s much easier to put together a picture and say to local authorities, ‘Look, this could be potentially how the virus is spread, this is what the bats are doing.’ ”
U.S. officials are so concerned about Marburg becoming a global threat that the CDC is seeking funding from the Pentagon’s Defense Threat Reduction Agency to cover the cost of the bat trackers, which are about $1,000 each. The CDC is hoping to track more of these Rousettus aegyptiacus bats in several other caves in Uganda.
Marburg’s potential to spread was made clear a decade ago when a pair of tourists on separate trips walked into the cave looking for adventure and walked out with the virus. A Dutch woman died 13 days after her visit. The other visitor, an American woman named Michelle Barnes, survived after a long, painful illness. The cave was closed to tourists in 2008.
Marburg was first identified in 1967 when a shipment of infected African green monkeys from Uganda was sent to laboratories in Marburg and Frankfurt, Germany, and Belgrade, in then-Yugoslavia. Seven lab workers died within about a week. Since then, a dozen outbreaks have been reported, killing hundreds of people. Most took place near bat-infested caves or mines, including one last fall along Uganda’s eastern border with Kenya. Of four family members sickened, only one survived.
For the CDC scientists, success hinges on getting the tracking units, which are half the size of a pen cap, to stay on a bat body that is only about six inches long. A practice run in Atlanta with the same device on the same kind of bat in a special CDC laboratory failed. Trackers slipped off or were chewed by the bats.
“I have no idea how well this is going to go because it’s the first time we’ve tried it,” Towner said. “It could end up in total flames