The Ebola outbreak in west Africa has just entered its second year, though it’s only now its origins have been pinpointed. Researchers from the Robert Koch-Institute in Germany have identified Ebola-infected bats as the most likely reservoir and therefore origin of the infection that has gripped west Africa and garnered the world’s attention in the past year. This is in contrast to suspicions of contaminated bush meat or fruit bats being the origin, as suggested earlier in the outbreak.
[caption id="attachment_39" align="alignleft" width="300"] Under the electron microscope: Ebola. Image by Cynthia Goldsmith of CDC. CC2.0.[/caption]
Study leader Dr Fabian Leendertz said “"We monitored the large mammal populations close to the index village Meliandou in south-eastern Guinea and found no evidence for a concurrent outbreak.” This suggested that the second route of infection, through exposure to infected insectivorous bats, was the most likely scenario.
Ebolavirus epidemics typically originate in animals other than humans, and previously fruit bats or contaminated animal meat have been suspected as the source. The original human case was two-year-old Emile Ouamouno, a boy local to Meliandou. Members of his family subsequently became ill. This was considered inconsistent with food-borne transmission which typically affects adults simultaneously with children.
The Germany study conducted interviews with villagers from Meliandou, which is located near forested areas. They identified a hollow tree inhabited by a large colony of free-tailed insectivorous bats around which children used to play, according to local reports. This exposure to infected bats seems a more likely route of transmission and may have resulted in the Ebola outbreak being battled today.
Following this first case in Meliandou, Ebola spread to several countries in west Africa and remains entrenched in Guinea, Sierra Leone, and Liberia. It has taken the lives of over 7,800 people and continues to spread. A lacklustre response from the World Health Organization, together with a multitude of unfortunate factors, has made this the worst outbreak of Ebola since its discovery in 1976. Reports suggest it could be late-2015 before the outbreak finally subsides.