Ebola is making headlines worldwide today, but the origins of the disease go back between 16 and 23 million years, according to new research.
Filoviruses, the group of microorganism that include Ebola and the deadly Marburg virus, can be traced back to the Miocene Epoch. This was a period on Earth during which grasslands and kelp gardens first became prominent on the land and sea. Great apes also first evolved during this time, leading to the wide range of primates in the world today. During the period, Ebola and Marburg evolved into separate families of organisms, becoming genetically distinct from each other.
The Marburg virus can lead to hemorrhagic fever inn victims of the disease. It was first identified in Germany during the 1960's.
Most biologists believed, prior to this study, that filoviruses first came into existence around 10,000 years ago, soon after the end of the last major Ice Age. This new study significantly pushes back the measured age of the deadly virus.
The current strain of Ebola infecting thousands of people in Africa and beyond may have a much more modern lineage origin than pointed out in this study. However, the research does show when the virus first evolved into a unique lifeform, apart from the Marburg virus.
Fossil gene are pieces of genetic code carried by viruses that infect host bodies. One of these genes, VP35, was found in two species of voles, as well as a pair of different types of hamsters. These two forms of rodent genetically separated from each other during the early Miocene Epoch. Presence of the code in both hamsters and voles suggests Ebola evolved previous to that time.
"These rodents have billions of base pairs in their genomes, so the odds of a viral gene inserting itself at the same position in different species at different times are very small. It's likely that the insertion was present in the common ancestor of these rodents," Derek Taylor of the University at Buffalo, said.
Ebola outbreaks have occurred from time to time, since 1976. Mystery still surrounds the events that made the virus so prevalent 38 years ago.
Researchers believe this study could assist investigators developing vaccines to emerging viruses.
"When they first started looking for reservoirs for Ebola, they were crashing through the rainforest, looking at everything - mammals, insects, other organisms. The more we know about the evolution of filovirus-host interactions, the more we can learn about who the players might be in the system," Taylor told the press.
Genetic study of Ebola and when the virus first evolved was profiled in the journal PeerJ.
