Archive for June, 2012

Science| Special Issue: H5N1 [exploring the "supervirus" controversy]

29 June, 2012

See on Scoop.itVirology News

“Introduction
The publication in this issue of these research papers on the airborne tranimssion [sic] of H5N1 marks the end of 8 months of controversy over whether some of the data, now freely accessible, should be withheld in the public interest.”

 

I think this is an important landmark in the so-called “dual use” debate: that is, the propensity of bodies in the US to attempt to regulate the release of information that MAY be usable in the making of bioweapons, or be usable in bioterror attacks.

 

Let us diffidently point out at this juncture that it is only really the superpowers who are definitively known in recent years to have had bioweapons programmes – apart from apartheid-era South Africa, that is! – and that damn nearly ANYTHING published on transmission or mechanisms of pathogenicity of human or animal pathogens (or even plant, for that matter) could be termed “dual use” if someone wanted to – and censored as a result.

 

It is also – as I tire of pointing out – possible to PROTECT against H5NX viruses using conventional vaccines right now – and the new universal flu vaccines coming on stream will almost certainly make this even more feasible.

 

The fact is that H5N1 flu is an ever-present threat to people living in Egypt, Indonesia, Cambodia, Viet Nam, Thailand and China – WITHOUT being weaponised.  It is no more than a notional threat to the US or Europe – and keeping information that could help in understanding how or how soon the virus could mutate to pandemicity out of people’s hands, is simply stupid. 

See on www.sciencemag.org

Nobel fight over African HIV centre

28 June, 2012

See on Scoop.itVirology News

Laureates question choice of interim scientific director.

See on www.nature.com

How Seanan McGuire Perfected Her Fictional Zombie Virus

27 June, 2012

See on Scoop.itVirology News

When Seanan McGuire set out to write her Newsflesh trilogy, she went to some extreme lengths to make her zombie virus as realistic as possible….

 

OK, ONE more on zombie apocalyspes (thanks @gussilber)!  Except she didn’t: a quote-

“when those two viruses met, they had babies, and what you got was a shifting-antigen flu that does not leave the body under any circumstances but is capable of turning into something that converts human tissue into more of the virus. And that’s how we got Kellis-Amberlee, which makes zombies” – don’t make it for me.  Human tissue turning into viruses = bloody slime, NOT walking corpses!  Rabies: now THERE’S yer zombie virus!

See on www.wired.com

Complete Genome Sequence of a New Circular DNA Virus from Grapevine

26 June, 2012

See on Scoop.itVirology and Bioinformatics from Virology.ca

“A novel circular DNA virus sequence is reported from grapevine. The corresponding genomic organization, coding potential, and conserved origin of replication are similar to those of members of the family Geminiviridae, but the genome of 3,206 nucleotides is 4% larger than the largest reported geminiviral genome and shares only 50% overall sequence identity.”

Interesting stuff!  These novel ssDNA viruses are popping up everywhere – probably because they ARE everywhere, well adapted to natural hosts, only rarely transmitted to crop species, and we only stumble upon them by deep sequencing.  Or blind luck.

See on jvi.asm.org

Corrupted Proteins Spread Disease | The Scientist

23 June, 2012

See on Scoop.itVirology News

“Many neurological diseases are caused by misfolded proteins that gather in large, destructive clumps, causing neuronal degeneration. Some of these proteins can also convert normal versions into their own twisted images, thus spreading the disease throughout the brain. The classic examples are prion diseases like mad cow disease and Creutzfeld-Jacob disease (CJD). They are caused by misshapen forms of the PrP protein, which corrupts the shapes of normal PrP.

Now, new research published today in the Proceedings of the National Academy of Sciences suggests that Alzheimer’s disease might work in a similar way. Its hallmarks include tangled clumps of amyloid-beta, a peptide (protein fragment) that aggregates in large plaques, which according to the new study, can seed more protein clusters, creating a wave of plaques that spreads through the brain.”

 

Interesting!  As a non-specialist, I have long been struck by the apparent similarities between prion diseases and Alzheimer’s – and now it has been shown that they really are similar in causation.

I just wonder how much of my brain is affected….

See on the-scientist.com

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

Non-canonical translation in RNA viruses

23 June, 2012

See on Scoop.itVirology News

“Viral protein synthesis is completely dependent upon the translational machinery of the host cell. However, many RNA virus transcripts have marked structural differences from cellular mRNAs that preclude canonical translation initiation, such as the absence of a 5′ cap structure or the presence of highly structured 5′UTRs containing replication and/or packaging signals. Furthermore, whilst the great majority of cellular mRNAs are apparently monocistronic, RNA viruses must often express multiple proteins from their mRNAs. In addition, RNA viruses have very compact genomes and are under intense selective pressure to optimize usage of the available sequence space. Together, these features have driven the evolution of a plethora of non-canonical translational mechanisms in RNA viruses that help them to meet these challenges. Here, we review the mechanisms utilized by RNA viruses of eukaryotes, focusing on internal ribosome entry, leaky scanning, non-AUG initiation, ribosome shunting, reinitiation, ribosomal frameshifting and stop-codon readthrough. The review will highlight recently discovered examples of unusual translational strategies, besides revisiting some classical cases.”

 

Great article for anyone interested in how RNA viruses subvert cellular processes.

See on vir.sgmjournals.org

Condoms not effective against HPV or herpes

23 June, 2012

See on Scoop.itVirology News

“Viral STDs make up the modern “4-H club.” Herpes simplex virus (HSV), human papilloma virus (HPV), hepatitis (B and C), and HIV are the most common STDs, causing pain, cancer, liver disease and AIDS, respectively.

Condoms significantly decrease transmission rates of the most life-threatening viruses, HIV and hep B and C.

Unfortunately, condoms do not do an adequate job of protecting against human papilloma or herpes simplex virus infections. Women diagnosed with HPV are often mystified and frustrated, having been “super careful,” or picky, in choosing intimate partners and faithfully using condoms for all intercourse.

But UCSF researchers have shown these viruses to be present on genital skin with no symptoms that might prompt diagnosis and treatment. That means HPV and HSV can be deposited on the condom’s outer surface from viral particles living on the scrotum, penile shaft not covered by the condom or vaginal/vulvar tissues.”

 

Interesting – because it’s been known a while that condoms are less effective in preventing spread of HPV than for bacterial STDs and HIV, and now we know why.  The only things that can really prevent the transmission of these agents, in the absence of abstinence, is vaccination.

See on www.sfgate.com

[dsRNA] Treatment for deadly bee virus promising

23 June, 2012

See on Scoop.itVirology News

“There’s buzz about a new treatment that could save bee populations from a deadly virus.
Researchers at the University of Manitoba have found a way to suppress the deformed-wing virus (DWV), which has had catastrophic effects on bee colonies worldwide, causing many to have crumpled or deformed wings.
Entomology PhD student Suresh Desai fed his bees double-stranded RNA, a treatment that prevented the virus from expressing itself in the host.
“It gives us a little bit of hope that we can manage this virus, because there is no control mechanism right now,” he said.
The study, published online on Insect Molecular Biology on June 12, showed bees fed the double-stranded RNA in a syrup and then inoculated with the virus had a much better survival rate than those who weren’t. RNA is much like DNA, but is in a single strand. It carries the genetic material of some viruses, including DWV. RNA is taken from the DWV and then converted into a double strand. When introduced in the bee, it suppresses the viral RNA.”

 

I find it fascinating that the dsRNA that we as plant virologists grew to know and love in the 1980s – because it’s easier to isolate from plants than ssRNA, and far more stable – has newly become so much more useful as an anti-viral therapeutic.  And you can isolate a tonne of dsRNA from virus-infected insects, too, so it’s also interesting why exogenous material should be effective.

See on www.winnipegfreepress.com


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