Commentary
H7 Q226L In Shanghai and Anhui H7N9 Cases
Recombinomics Commentary 20:15
April 1, 2013 The recent H7N9 cases in China have caused considerable concern. This serotype had never been found in humans previously and only one fatal bird flu case that was not H5N1 had been reported (H7N7 in The Netherlands in 2003. Two of the H7N9 cases were fatal (87M and 27M), while one was critical (35F).
The WHO Chinese Influenza Research Center released a full set of sequences for all three cases. Each had PB2 E627K, as well as a 15 BP deletion In N9. PB2 E627K is a mammalian adaptation and was present in both H5N1 transmission experiments (CDC and EMC) which used an avian PB2.
All three of the H5N1 transmission studies introduced the receptor bind domain change Q226L to increase affinity for mammalian receptors.
Q226L has never been reported in natural H5N1 isolates.
Two of the H7N9 cases, A/Shanghai/2/2013 and A/Anhui/1/2013 have Q226L, raising serious pandemic concerns.
Post to me or FReep mail to be on/off the Bring Out Your Dead ping list.
The purpose of the “Bring Out Your Dead” ping list (formerly the “Ebola” ping list) is very early warning of emerging pandemics, as such it has a high false positive rate.
So far the false positive rate is 100%.
At some point we may well have a high mortality pandemic, and likely as not the “Bring Out Your Dead” threads will miss the beginning entirely.
*sigh* Such is life, and death...
So we are supposed to panic, just not yet.
This strain would be a kick in the tail...our vaccines are geared to H1N1 strains. I watched H3N8 jump species and it was a over a year before anyone got a handle on the disease.
Imagine someone selfish enough to throw thousands of pigs into a river to float his problems on everyone downstream.
Imagine people drinking water from that river.
Communism is the most selfish of governments in history, with the most hypocritical history of being "for the people".
Angry Birds!
Nah! Rotting carcass’ in water never caused any problems!
For a little clarity, the “H7” in its nomenclature stands for “Hemagglutinin (HA) type 7”. There are at least 17 different HA antigens, numbered 1-17.
The first three hemagglutinins, H1, H2, and H3, are found in easily transmissible among people, human influenza viruses.
H1N1 was the type of flu that caused the Spanish Flu in 1918, killing millions around the world. But iterations of H1N1 since have been limited by “near immunity” in most people. The recent exception being the Ukraine H1N1 flu epidemic, which traumatized that region, with some of the dead having lungs so damaged they looked black and burned.
However, the flu with the most potential for an epidemic the likes of which has never been seen on Earth, the potential “thermonuclear bomb” of influenza, is H5N1.
A highly pathogenic avian flu virus of H5N1 type has been found to infect humans at a low rate. It has been reported that single amino acid changes in this avian virus strain’s type H5 hemagglutinin have been found in human patients that “can significantly alter receptor specificity of avian H5N1 viruses, providing them with an ability to bind to receptors optimal for human influenza viruses”.
And no one has even limited immunity to H5N1. There is no vaccine for it.
Which brings us to the other side of the equation, the “N” factor, which stands for “Neuraminidase”. There are at least 200 known kinds, the first four of which (N1-N4) have been around so long that parts of them have been integrated into the human genome. There are five other “N” factor subtypes, but only N1 and N2 are commonly found in people.
Put simply, the “H” factor is how the virus enters host cells, and after reproducing inside them and killing the cell, the “N” factor is how they get out of the dead cell before it is destroyed by the body.
All anti-viral drugs are designed to inhibit the “N” factor, to keep the virus trapped inside the cell until it is destroyed along with them.
While it is much less likely to become incredibly transmissible between humans, yet still retain lethality, like H5N1, H7N9 does have possibilities, perhaps by swapping genetic information with other influenza viruses.