Posts Tagged ‘aerosol transmission’

Five Mutations Make H5N1 Airborne | The Scientist

23 June, 2012

See on Scoop.itVirology News

“After more than 6 months of heated discussion, the second group that succeeded in making the H5N1 avian flu transmissible between ferrets, considered a good model for human transmission, has published its results. The paper, which came out today (June 21) in Science, demonstrates that only five mutations are needed to confer this aerosol transmissibility among mammals, and that re-assortment between different types of viruses—a technique used by the other group, which published its results last month in Nature—is not necessary.

Said Fouchier in a press conference “We both find … loss of glycosylation at the tip of the HA molecule, and this loss of glycosylation seems to increase the receptor binding specificity of the HA”. And though not all the mutations identified in the two studies match, “the mutations that are not identical still have a similar phenotypic trait,” he added.”

 

So this is what all the fuss was about?  This is what the NSABB did not want everyone to know?  How could they POSSIBLY think that the international virology and infectious disease community should be kept in the dark about this?  What this work has done has pointed the way along a path that will lead us to understand why and how influenza viruses change in order to more effectively get transmitted when they switch hosts – which is a good thing, surely.

And yet all they see is bioterrorism.

See on the-scientist.com

Avian flu viruses which are transmissible between humans could evolve in nature

23 June, 2012

See on Scoop.itVirology News

It might be possible for human-to-human airborne transmissible avian H5N1 influenza viruses to evolve in nature, new research has found.

The findings, from research led by Professor Derek Smith and Dr Colin Russell at the University of Cambridge, were published June 22 in the journal Science.
Currently, avian H5N1 influenza, also known as bird flu, can be transmitted from birds to humans, but not (or only very rarely) from human to human. However, two recent papers by Herfst, Fouchier and colleagues in Science and Imai, Kawaoka and colleagues in Nature reveal that potentially with as few as five mutations (amino acid substitutions), or four mutations plus reassortment, avian H5N1 can become airborne transmissible between mammals, and thus potentially among humans. However, until now, it was not known whether these mutations might evolve in nature.
The Cambridge researchers first analysed all of the surveillance data available on avian H5N1 influenza viruses from the last 15 years, focusing on birds and humans. They discovered that two of the five mutations seen in the experimental viruses (from the Fouchier and Kawaoka labs) had occurred in numerous existing avian flu strains. Additionally, they found that a number of the viruses had both of the mutations.
Colin Russell, Royal Society University Research Fellow at the University of Cambridge, said: “Viruses that have two of these mutations are already common in birds, meaning that there are viruses that might have to acquire only three additional mutations in a human to become airborne transmissible. The next key question is ‘is three a lot, or a little?’ “

 

So: was it a good idea to publish those two papers on mutating H5N1 viruses, or not?  Given that as I and many other more famous people pointed out, if you don’t know what makes the viruses mammal-to-mammal transmissible, you don’t know what to look for – and now we do, and look what they found.  This story will run, and run, and run – so we really, really should include an H5 consensus HA in seasonal flu vaccines!!

See on www.sciencedaily.com

H5N1: coming soon to a ferret near you?

20 December, 2011

From Nature News today:

“It is a nightmare scenario: a human pandemic caused by the accidental release of a man-made form of the lethal avian influenza virus H5N1.

Yet the risk is all too real. Since September, news has been circulating about two groups of scientists who have reportedly created mutant H5N1 variants that can be transmitted between ferrets merely breathing the same air, generally an indicator that the virus could also spread easily among humans.”

And yet…and yet…we won’t know, will we? Until and unless a human catches the ferret-bred virus, OR one develops all by itself out here in the world, that has the same mutations – which we won’t know about, unless we are told what those are.

Wednesday 21st December
And updating this story: the BBC has an interview with Anthony Fauci - formerly head of the US NIH – on what will be happening with the information.  The answer – it will be “redacted”, so the conclusions are published, but not the methods the groups used to produce their viruses.  Apparently the redacted details will be shared with national health authorities and “reputable” universities and institutes.

I would be very interested to see who makes those decisions, and who is considered ‘reputable” – our group, at the best university in Africa and 103rd best in the world by some rankings, are not even reputable enough to be able to order bluetongue virus genes from DNA synthesis companies, for example.

Watch this space….


Follow

Get every new post delivered to your Inbox.

Join 529 other followers