Avian H5N1 influenza viruses in the wild may be one small step away from spreading effectively between mammals. That is the sobering message from a controversial study by Yoshihiro Kawaoka at the University of Wisconsin–Madison, published online by Nature1 after months of debate about how to release the findings publicly.We knew that H5N1 was only few mutations away from H2H since well before as soon as the security Mafia's heads started to explode in an orgy of security theater.
“After wanting to read it for so long, it was like eating again after fasting,” says Vincent Racaniello, a virologist at Columbia University in New York. “And it does not disappoint.”
H5N1, commonly known as bird flu, is highly pathogenic and often lethal in humans, but it cannot spread efficiently between people and cases seem to be rare. To find out if H5N1 could evolve easy transmissibility between humans, Kawaoka and his team mutated its haemagglutinin (HA) gene, which produces the protein that the virus uses to stick itself to host cells. Because flu viruses in the wild can also gain new properties by swapping genes, the researchers combined this gene with seven others from a highly transmissible flu virus, the H1N1 strain that caused a pandemic in 2009.
Kawaoka found that the hybrid virus could spread between ferrets in separate cages after acquiring just four mutations. Three of these allow the HA protein to stick to receptor molecules on mammalian cells, and the fourth stabilizes the protein. “Before we initiated this experiment, we knew that receptor specificity is important,” says Kawaoka. “We didn’t know what else was needed.”
Worryingly, some Middle Eastern H5N1 strains can already recognize human receptors2. Kawaoka’s work suggests that they could be just one stabilizing mutation away from being able to spread between humans. Discovering “that HA needs to be stable to be transmissible through the air between mammals” is a key finding, says influenza virologist Wendy Barclay at Imperial College London.
The post 911 security apparatus doing more harm than good.
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