See the next post for the thinking of the guy who led the smallpox eradication effort regarding H5N1 gain-of-function research.
From the journal Science, December 5:
Some scientists examining mutations found in H5N1 viruses fear major outbreak is imminent but others say pathogen remains unpredictable
If the world finds itself amid a flu pandemic in a few months, it won’t be a big surprise. Birds have been spreading a new clade of the H5N1 avian influenza virus, 2.3.4.4b, around the world since 2021. That virus spilled over to cattle in Texas about a year ago and spread to hundreds of farms across the United States since. There have been dozens of human infections in North America. And in some of those cases the virus has shown exactly the kinds of mutations known to make it better suited to infect human cells and replicate in them.
No clear human-to-human transmission of H5N1 has been documented yet, but “this feels the closest to an H5 pandemic that I’ve seen,” says Louise Moncla, a virologist at the University of Pennsylvania. “If H5 is ever going to be a pandemic, it’s going to be now,” adds Seema Lakdawala, a flu researcher at Emory University.
Others are more sanguine, noting that similarly menacing avian flu viruses, such as one called H7N9, have petered out in the past. “Why didn’t H7N9 end up being easily human-to-human transmissible and cause a pandemic?” asks Caitlin Rivers, an epidemiologist at the Johns Hopkins Center for Health Security. “I feel like there’s really no way to estimate and it could go either way.”
Ever since H5N1 first caused an outbreak in humans in Hong Kong in 1997, sickening 18 who had been in contact with infected poultry and killing six, the avian virus has been high on lists of potential pandemic agents. Scientists have since built up a picture of the minimum changes H5N1 likely needs to spread widely in humans: mutations in its polymerase, the enzyme the virus uses to copy its genome, and in its hemagglutinin—the H in H5N1—the protein the virus uses to attach to cells, to stabilize it for airborne transmission and help it better bind to cells in the human upper airways.
A slew of recent findings all seem to suggest the risk of the current H5N1 clade in cattle and birds causing a pandemic is actually higher than previously thought. A study looking at blood samples from workers at H5N1-infected dairy farms in Michigan and Colorado found that many human infections go undetected, each one offering the bovine virus more chances to adapt to us. A preprint out this week indicates currently circulating clade 2.3.4.4b viruses are better at binding to human epithelial cells in the airways than previous versions of H5N1. And a Science paper out today shows in lab studies that a single mutation at one hemagglutinin site, dubbed 226L, is enough to shift the virus’ preference from the avian-type cell surface protein to human-type receptors. Many scientists had thought at least two mutations were required. A switch based on just one mutation “means the likelihood of it happening is higher,” says Jim Paulson of Scripps Research, one of the authors.
So why hasn’t H5N1 touched off a pandemic yet?
One simple answer is that the virus may just need more time to hit the right combination of mutations. The high mutation rate of influenza viruses should tip the odds in H5N1’s favor: “My rule of thumb is that one in 4000 [virus] particles will have a mutation at the amino acid that you are interested in,” Paulson says. Indeed, one polymerase mutation the virus likely needs, dubbed 627K because it leads to the amino acid lysine (K) at position 627 of the protein, has been found several times in strains infecting mammals but also in virus isolated from the first human case associated with the U.S. outbreak in dairy cows....
....MUCH MORE
And those Dutchmen?
January 2012Psychotic Dutch Scientists: "Killer flu doctors: US censorship is a danger to science"
The grins and giggles guys [a little alliteration? -ed] we first met in "Dutch Scientists Have Genetically Altered the H5N1 Bird Flu Virus to Make it More Contagious" (could kill half humanity) are back in the news.
From The Independent:
Dutch lab that created deadly bird flu virus attacks America for redacting its research.
December 2012
More Wacky Dutch Scientists: "Dutch to send mobile clinics to euthanise people in their own homes"
Let's hope they get the right address.December 2012
Earlier we posted on the Dutch scientists who
a) Weaponized bird flu to the point that it could kill half the people in the world.
b) Planned to publish the recipe.
c) Got crabby when told that might not be a good idea.
Here's another group....
UPDATE: Dutch Scientists Agree to Redact Details of Super-lethal (50% Kill Rate) Genetically Modified Bird Flu
The third chapter of the nuttiness:
Psychotic Dutch Scientists: "Killer flu doctors: US censorship is a danger to science"
Chapter the Fourth:
World Health Organization: Okay to Publish Super-lethal Bird Flu Recipe
May 1, 2023
RISK: Don't Look Now But H5N1 Bird Flu Has Been Found To "Efficiently" Spread In Certain Mammals
And F***ed up:
Via "L’olandese del Coronavirus. Ed altri scriteriati."
Oh, and this "Fouchier study reveals changes enabling airborne spread of H5N1":
A study showing that it takes as few as five mutations to turn the H5N1 avian influenza virus into an airborne spreader in mammals—and that launched a historic debate on scientific accountability and transparency—was released today in Science, spilling the full experimental details that many experts had sought to suppress out of concern that publishing them could lead to the unleashing of a dangerous virus....
