The Ebola virus epidemic made headlines around the world both in relation to the death toll among hundreds of people from four African countries and the handful of international aid workers who have contracted the disease. Ebola is a serious viral infection with a high mortality rate; common signs of the disease include bleeding from mucous membranes and puncture sites. If the infected person does not recover, death due to multiple organ dysfunction syndrome occurs.
The West African outbreak began following the cross-species transmission of Ebola virus from an animal reservoir, most likely bats.
The question of how far did the Ebola virus mutate was first raised by Harvard University researchers who investigated Ebola samples and blood samples relating to infected people in Sierra Leone. The inference of the genetic research was that the virus was rapidly mutating. This was reported to the journal Science, in a paper titled “Genomic surveillance elucidates Ebola virus origin and transmission during the 2014 outbreak”.
Further study, undertaken by Professor Jeremy Luban from the University of Massachusetts Medical School, infers that significant adaptation took place. This is based on a review of Ebola virus genomic sequences, which allowed the research group to track patterns of mutation.
This research discovered found that mutations of the gene that encodes the Ebola virus glycoprotein had taken place. The consequence of this was to increase the virus’ ability to infect cells of humans and other primates. This particular mutation emerged early in the outbreak at the point where case numbers significantly increased and this quickly became the dominant virus type circulating in the outbreak.
The research shows how specific amino acid substitutions in the Ebola virus glycoprotein led to increased tropism in human cells. A ‘tropism’ is a growth in response to a stimulus.
In a research brief, Professor Luban explains further: “It’s important to understand how these viruses evolve during outbreaks. By doing so, we will be better prepared should these viruses spill over to humans in the future.”
The research has been published in the journal Cell. The research is titled “Ebola Virus Glycoprotein with Increased Infectivity Dominated the 2013–2016 Epidemic.”
