The Search for the Source of the 2014 Ebola Outbreak

The source of the current Ebola outbreak – which has thus far claimed 7600 lives in West Africa – has not yet been firmly established. However, the first casualty, a two-year old child in Meliandou, Guinea, lived and played with his family and friends in close proximity to a tall, hollow tree that was home to thousands of bats.

But before scientists could establish a clear cause-and-effect relationship between the bats in the tree and the little boy’s death – the tree burned to the ground, killing all the bats. And the villagers disposed of the bodies – in many cases through consumption – before the scientists reached the scene. The best they could do with the DNA they were able to salvage was to definitively identify the species of bat as Mops condylurus, the insectivorous free-tailed bat.

Bats play an important role in the area’s eco-system. The fruit-eaters pollinate flowers and spread seeds while the insect eaters keep the mosquito population in check. Bats also form a regular part of the people’s diet and the children enjoy catching and playing with them.

According to a 2013 study, bats play host to approximately 60 different viruses – far more than earth-bound rodents do. And it is possibly because of the metabolism and heat that their bodies generate in flight that they can carry and spread the viruses while remaining immune to them.

Scientists tested other bats in the area – as well as larger animals – and found no trace of Ebola or any other disease among them. Nevertheless, the Guinea government has banned the hunting and eating of bats.

The death of the two year old in Dec. 2013 was followed by the death of his sister, mother and grandmother. It was not until March of 2014 that the source of their illness was identified as Ebola. By summer, Ebola had spread across borders into Sierra Leone, Liberia and Nigeria – in the worst outbreak of the disease ever recorded.