a reply to: badgerprints
I hope I brought this all together to help bring out a little more of what your guy was trying to say in his article. The big idea from all these
references below is that as the virus adapts to its new niche it does so with one end goal, maximize their infectivity , or another way to think of it
is the best fit for their human host .
Here are a few papers and info I will try and bring together about the mutations and the significance from several science papers and researchers. I
think the greatest significance is what they summarize in terms of transmission and diagnostic reliability of current tests. It is very unlikely that
the mutations would all of a sudden accumulate into an entire new mode of transmission as that’s not normally seen. The speculation about it
becoming airborne like the flu is due to the following reason that the ebola virus contains similar fusion proteins. This mechanisms of membrane
fusion is seen in enveloped viruses such as influenza, HIV, or Ebola when they enter their respective host cells. ebola is also very different in many
ways, for example, more than one virus particle can enter a host cell.
Science jargon describing these proteins in case you want to look it up further. tammlab.medicine.virginia.edu...
virus outer viral 'fusion proteins' (GP) spikes resemble that of influenza. This is expected as both are believed to be Class I fusion
proteins...Both are also homotrimers and undergo pH-dependent conformational change in the late endosome. The interaction of fusion proteins with the
endosome is how these viruses 'trick' their way out of the late endosome, which in practice means these viruses pop out of the cellular 'trash can'
and into the cytoplasm. (SIB, 2014)
IMPORTANT TO THE DESIGN OF THE STUDY AND TO NOTE IS THAT THIS WAS DONE THE FIRST 78 DAYS OF OUTBREAK in Sierra Leone!! Another important fact is that
the repeated samples from same patients allowed for looking at the virus when they got infected as well as what it ended up as genetically after
reproducing massively in the same patient during the infection. As they said, “clearer view into how the virus can change in a single individual
over the course of infection”.
The question that’s hot is what has it done since last March!!
This current rate of mutations may be driven by the fact human to human transmission is resulting in mutations needed for adapting to this new host.
Historically, the previous outbreaks have been small and this certainly affects something called antigenic drift. The benefit of a high mutation rate
in Ebola 2014 is different -- the genetic changes in Ebola-2014 allow for rapid exploration of the entire fitness landscape in a brand new host --
humans. See infographic on this site ( I dont know how to insert the damn image!!!) www.operonlabs.com...
The problem is that accumulated Ebola mutations will scale with the size of the population infected. Which is why its so important to stop this at its
source. ” The idea that the Ebola-2014 Virus jumped species, but is now somehow 'static' or 'frozen in time' is a mistake. The Ebola-2014 virus is
undergoing a period of rapid adaptation in human hosts, as evidenced by the Ebola RNA sequences deposited in Genbank, and the studies referenced with
this article. Hopefully, interventions (like contact tracing) will be able to stop Ebola-2014 before the virus optimizes its genotype” .
Up to four different Ebola-2014 viral sub-clades (groups of genetically related Ebola isolates) have circulated between humans since the onset of the
2014 Ebola outbreak.
As the number of people affected by the 2014 Ebola outbreak has grown, so has the number of Ebola unique viral mutations and unique viral genetic
lineages. We can expect Ebola 2014 viral lineages to grow as some function f(i) proportional to the number of people infected with Ebola.
However, the mutations that are happening are very significant in terms of the infection mechanism of this virus variant as well as in terms of rate
that’s never been seen before in previous outbreaks. Ebola Mutation Rate: Analysis of the available research suggests that the Ebola 2014 virus is
currently mutating at a rate 200% to 300% higher than historically observed (Gire, 2014). Furthermore, the Ebola-2014 virus's mutation rate of 2.0 x
10−³ subs/site/year is nearly identical to Influenza A's mutation rate of 1.8 x 10−³ subs/site/year (Jenkins, 2002). This means Ebola 2014 is
mutating as fast as seasonal flu.
DISCLAIMER to make sure you note and understand exactly what these scientist demonstrate with this research and what they CAN NOT SAY!!
This paper contains no evidence (for or against) alternate modes of transmission for Ebola, nor is this paper postulating that genetic changes have
impacted EVD clinical presentation (although evidence for this has started to emerge). This paper is simply demonstrating what appears to be a rapid
rate of evolution in the Ebola 2014 Virus. Many recent Ebola viral mutations have been synonymous mutations, some have been in intergenic regions,
while others are non-synonymous substitutions in protein-coding regions. All have unknown impact at the present time. Such questions should be the
subject of future scientific research. This article simply points out that Ebola in 2014 is undergoing rapid mutation and adaptation. The future
implications of Ebola's rapid evolution are unclear.
Ebola in Zoonotic Reservoir: Viral Genome adapted to Fruit Bats. (Green)
Ebola in Human Hosts: Viral Genome adapted to Humans. (Red)
Ebola Genotype will move Green -> Red during serial passage through Humans.
In response to an ongoing, unprecedented outbreak of Ebola virus disease in West Africa, a team of researchers has rapidly sequenced and analyzed more
than 99 Ebola virus genomes. Their findings could have important implications for rapid field diagnostic tests.
 Genomic surveillance elucidates Ebola virus origin and transmission during the 2014 outbreak. (Gire et al, 2014).
 Rates of Molecular Evolution in RNA Viruses: A Quantitative Phylogenetic Analysis. (Jenkins et al, 2002).
 Isolates of Zaire ebolavirus from wild apes reveal genetic lineage and recombinants. (Wittman et al, 2007).
 Ebola Recombination: Recombinomics Commentary. (Niman, 2007).
 Evolutionary Dynamics: Exploring the Equations of Life. (Nowak, 2006).
edit on 22-10-2014 by bella2256 because: (no reason given)