A group of researchers from the Robert Koch Institute in Germany found that the Ebola outbreak in West Africa likely began when a young boy played too close to an infected group of bats. Their findings were published Tuesday in the journal EMBO Molecular Medicine.
The Ebola outbreak, which has killed 7,857 people so far, is believed to have started with 2-year-old Emile Ouamouno, who died in December 2013. Ebola epidemics start in animals and spread to humans. The virus can hide in larger mammals, infecting humans through meat or other direct contact. But the outbreak could have started with a much smaller animal: bats.“We monitored the large mammal populations close to the index village Meliandou in south-eastern Guinea and found no evidence for a concurrent outbreak,” said Fabian H. Leendertz of the Robert Koch Institute, who led the study.
Fruit bats have been a source of earlier Ebola virus outbreaks, spreading to humans who kill the bats for meat. Eating bats is a common practice in south-eastern Guinea, but that doesn’t appear to be the source in the most recent epidemic, researchers said. If bushmeat was the source, the adults in the village would have gotten sick before young Ouamouno, the study concludes.
In their four-week trip to Guinea in April, researchers visited Meliandou, the village where Ouamouno lived. They found a burned-out stump about 50 yards from the boy’s home. After talking with neighbors, they learned that Ouamouno used to play there with his friends. When the tree caught fire in 2014, a “rain of bats” fell on the village, residents told the researchers.
The villagers collected the bats for the bushmeat, but disposed of them the next day after a government-led ban on the practice.
Tests of living bats nearby found no traces of the virus. No previous tests of the species have found Ebola either. Given the amount of bat meat eaten every year, this is a rare incidence, Leendertz concluded.
“If more bats carried the virus, we would see outbreaks all the time,” he told BBC News. “The Ebola virus must jump through colonies from bat to bat, so we need to know more.”
And killing the bats is not the answer to preventing another outbreak, he added.
“These bats catch insects and pests, such as mosquitoes. They can eat about a quarter of their body weight in insects a day,” he said. “Killing them would not be a solution. You would have more malaria.”