from Science – (LEFT TO RIGHT) MAMBU MOMOH; SIMBIRIE JALLOH; PARDIS SABETI; MIKE DUBOSE*
One of the big mysteries in the Ebola outbreak in West Africa is where the virus came from in the first place — and whether it’s changed in any significant ways. These unanswered questions could be making it more difficult to diagnose the disease and find treatments.
Now scientists are starting to get some answers. In a new paper in Science, researchers reveal that they have sequenced the genomes of Ebola from 78 patients in Sierra Leone who contracted the disease in May and June. Those sequences revealed some 300 mutations specific to this outbreak.
I wrote about this almost a month ago. There was something different about this outbreak and it might be due to new variants of the virus.
Now we have sequence data that shows this virus outbreak has a new strain(s) involved.
Researchers are also planning to study the mutations to see if any of them are affecting Ebola’s recent behavior. The number of mutations found is completely normal, and it isn’t necessarily the case that they’ll have a big effect. But it’s possible that something intriguing could turn up.
For example, this outbreak has had a higher transmission rate and lower death rate than others, and researchers are curious if any of these mutations are related to that. (Right now, social factors are thought to be the main causes of these two changes.)
Higher transmission rates coupled with lower mortality. That is what has usually been seen with other viral outbreaks in humans. Until there is a balance reached.
The changes are found throughout the genome and by studying them, they have been able to put together a ‘genealogy’ of the virus variants from the first outbreak in 1975.
I expect we will have treatments for this rather rapidly. Now that we have some data.
Tragically, this paper ends in something I have never seen before in a research paper:
In memoriam: Tragically, five co-authors, who contributed greatly to public health and research efforts in Sierra Leone, contracted EVD in the course of their work and lost their battle with the disease before this manuscript could be published. We wish to honor their memory.
Such brave people. Their pictures are at the top.