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In reply to the discussion: 16 Members of Doctors Without Borders Infected with Ebola, Nine Dead [View all]LovingA2andMI
(7,006 posts)77. That's not True....
"When viruses enter a cell, they make copies of their genetic information to assemble new virus particles. Viruses such as Ebola virus, which have genetic information in the form of RNA (not DNA as in other organisms), are notoriously bad at copying their genome. The viral enzyme that copies the RNA makes many errors, perhaps as many as one or two each time the viral genome is reproduced. There is no question that RNA viruses are the masters of mutation. This fact is in part why we need a new influenza virus vaccine every few years.
The more hosts infected by a virus, the more mutations will arise. Not all of these mutations will find their way into infectious virus particles because they cause lethal defects. But Osterholms statement that the evolution of Ebola virus is unprecedented is simply not correct. It is only what we know. The virus was only discovered to infect humans in 1976, but it surely infected humans long before that. Furthermore, the virus has been replicating, probably for millions of years, in an animal reservoir, possibly bats. There has been ample opportunity for the virus to undergo mutation.
More problematic is Osterholms assumption that mutation of Ebola virus will give rise to viruses that can transmit via the airborne route:
If certain mutations occurred, it would mean that just breathing would put one at risk of contracting Ebola. Infections could spread quickly to every part of the globe, as the H1N1 influenza virus did in 2009, after its birth in Mexico.
The key phrase here is certain mutations. We simply dont know how many mutations, in which viral genes, would be necessary to enable airborne transmission of Ebola virus, or if such mutations would even be compatible with the ability of the virus to propagate. What allows a virus to be transmitted through the air has until recently been unknown. We cant simply compare viruses that do transmit via aerosols (e.g. influenza virus) with viruses that do not (e.g. HIV-1) because they are too different to allow meaningful conclusions.
One approach to this conundrum would be to take a virus that does not transmit among mammals by aerosols such as avian influenza H5N1 virus and endow it with that property. This experiment was done by Fouchier and Kawaoka several years ago, and revealed that multiple amino acid changes are required to allow airborne transmission of H5N1 virus among ferrets. These experiments were met with a storm of protest from individuals among them Michael Osterholm who thought they were too dangerous. Do you want us to think about airborne transmission, and do experiments to understand it or not?
The other important message from the Fouchier-Kawaoka ferret experiments is that the H5N1 virus that could transmit through the air had lost its ability to kill. The message is clear: gain of function (airborne transmission) is accompanied by loss of function (virulence)."
http://www.virology.ws/2014/09/18/what-we-are-not-afraid-to-say-about-ebola-virus/
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16 Members of Doctors Without Borders Infected with Ebola, Nine Dead [View all]
Purveyor
Oct 2014
OP
Why is it when a nurse contracts Ebola in Dallas it's all about how she broke protocol, but
jtuck004
Oct 2014
#4
I think the odds come into play here. Let's see you have the meds in Africa treating hundreds
LiberalArkie
Oct 2014
#44
That's another possibility, thank you. Also, the people who are making the most $$$ from this aren't
jtuck004
Oct 2014
#27
Or, they don't want to admit that the protocol was incorrect or not communicated.
Hoppy
Oct 2014
#38
Doctors Without Borders don't have access to the same kind of facilities and money as US hospitals.
Voice for Peace
Oct 2014
#17
I doubt it. They, unlike you, seem to be aware of the impossible working conditions
kestrel91316
Oct 2014
#28
Dr. Frieden: "Looking back, we say we should have put an even larger team on the ground immediately"
pnwmom
Oct 2014
#60
Really really really hoping the vaccine trials show it to be safe AND effective.
kestrel91316
Oct 2014
#19
Hopefully the blood transfusions will be found to work. I know that they need more money to
jwirr
Oct 2014
#25
There's more money to be made curing the erectile dysfunction of Wall Street CEOs. eom
whereisjustice
Oct 2014
#53
Yes they mutate, but they do not do so as to completely change the mode of transmission
Marrah_G
Oct 2014
#74
They (The Rich) will contract vendors to build isolation units immediately
LovingA2andMI
Oct 2014
#71