Tracking the next pandemic: Avian Flu Talk |
H7N9 has mutated |
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jacksdad
Executive Admin Joined: September 08 2007 Location: San Diego Status: Offline Points: 47251 |
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Posted: January 11 2014 at 9:26am |
A tip of the hat to Cobber for finding this one. It deserves it's own thread.
H7N9 has mutated, may spread from human to human: expert2014/01/11 18:34:41
George F. Gao, the vice-president of Beijing Institutes of Life Sciences under the Chinese Academy of Sciences and deputy director-general of the Chinese Center for Disease Control and Prevention, told the Weekly that he and his research colleagues have broken down the mechanisms of transmission of the H5N1 and H7N9 avian flu viruses. The research team pointed out in a study published in Science magazine in September last year that they have identified mutations in four key sites of amino acids of the H7N9 strain and found that the virus has an ability to bind to human cells in the upper respiratory tract. Although the H7N9 and H5N1 viruses have not had the ability to widely spread from human to human, after undergoing genetic mutations and redistribution through mutations, they become better able to bind to human cells in the upper respiratory tract and can evolve into bird flu strains with the ability to transmit among humans, the team says. In nature, H7N9 is an avian flu virus, but it tends to bind to poultry cells in the lower respiratory tract, Gao said. He added that although the H7N9 virus can invade cells in the human upper respiratory tract, it only has a limited ability to transmit among humans. This winter, China reported several human cases of H7N9 bird flu, with two new cases reported Friday in eastern China's Zhejiang Province and one death in Fujian Province. The report said that H5N1 and H7N9 have been two of the the most lethal avian influenza viruses for humans in recent years. Since the first case of human influenza A H5N1 was reported in 1997 in Hong Kong, the virus has affected more than 60 countries around the world, with a fatality rate of 60 percent. After a number of human infections of the H7N9 virus have been reported in eastern China, mostly in the Yangtze River Delta region in late February 2013, more than 140 human infections of H7N9 have been reported in 12 provinces and cities in China, including 46 deaths, according to the report. Gao said that closing live poultry markets, adopting more intensive livestock farming practices and using the mass slaughter of live poultry are good measures to control the spread of the H7N9 epidemic. The Shanghai City government has announced it will shut down live poultry markets from the Lunar New Year holiday (Jan. 31) until April 30. (Cheng Chung-sheng and Y.L. Kao) http://focustaiwan.tw/news/acs/201401110017.aspx |
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"Buy it cheap. Stack it deep"
"Any community that fails to prepare, with the expectation that the federal government will come to the rescue, will be tragically wrong." Michael Leavitt, HHS Secretary. |
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jacksdad
Executive Admin Joined: September 08 2007 Location: San Diego Status: Offline Points: 47251 |
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I wish there was a more distinct timeline to determine if this is a recent change or just rehashing of an article from September, and I'd like some clarification of where the mutation has been seen. In patients or the lab? It's also a little confusing when the lead researcher is quoted as saying that "although the H7N9 virus can invade cells in the human upper
respiratory tract, it only has a limited ability to transmit among
humans".
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"Buy it cheap. Stack it deep"
"Any community that fails to prepare, with the expectation that the federal government will come to the rescue, will be tragically wrong." Michael Leavitt, HHS Secretary. |
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arirish
Admin Group Joined: June 19 2013 Location: Arkansas Status: Offline Points: 39215 |
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We're talking twenty five plus cases in eleven days! Something's changed and not for the better!
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Buy more ammo!
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jacksdad
Executive Admin Joined: September 08 2007 Location: San Diego Status: Offline Points: 47251 |
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Last year it emerged toward the end of the flu season as temperatures started to warm up, but it definitely got an earlier start this year and seems to have hit the ground running. Hopefully it's just the colder weather, but I have a feeling that there's more to the uptick in cases than that. And while the geographical spread is pretty impressive, I'm still surprised that Taiwan is still the only other country that's seen infections.
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"Buy it cheap. Stack it deep"
"Any community that fails to prepare, with the expectation that the federal government will come to the rescue, will be tragically wrong." Michael Leavitt, HHS Secretary. |
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RegiMental
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Seems to me that the chance of a Flu Pandemic is layered with chance upon chance. There is a chance that two nasty Flu viruses have to infect the same host at the same time. They have to have some genetic change that will make them more transmissible/virulent; they are just as likely (more likely?) to experience a change that will do nothing or be debilitating. Then for that to then go Pandemic, really that person has to be surrounded by a lot of people and people that are vulnerable to infection, move around a lot etc etc. Layers of chance there all the way. Could happen tomorrow, may never happen.
Of course, with H7N9, it is looking more and more likely. I feel like everyday we are dodging a bullet here and eventually one will hit. And who knows how bad that hit will be? What I don't get is that no government seems to be putting any pressure on China to put extra measure in place (better tests? Poultry Vaccine for H7N9? (is someone doing this? Seems a bit obvious to me)). Or insisting on a change in the way poultry is farmed/mass sold so better bio-containment is achieved? The Global powers seem to be all getting into bed economically with China and so I know there must be some leverage there. They all seem to be worried about economics and failing to see that if this hits and is as bad as some predict then there will be no economics to speak off. It will not be the mortality that will hits the most. If they say 100 million die then really that is less than 2% of Global population. However people staying away from any crowds out of utter utter fear will be the problem, especially in the Western world. Why oh why do the people who apparently run this joint not see this. |
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Kilt2
Adviser Group Joined: December 17 2007 Status: Offline Points: 7414 |
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when you see 100 h2h cases - shut the gates
we have the bug but no h2h spread as yet - i believe its coming though
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And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him.
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cobber
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i shouldn't be posting now as i should be doing other things, but just quickly.
Below is the abstract from Science magazine. It mentions HA H7N9 AH as having the ability to bind to both human and avian receptors. This gives the virus the ability to jump back and forth. Meaning increased mutation potential. It doesn't mean however that the virus will spread easily from human to human. My on personal interpretation is the virus has developed the ability to bind to human receptors it cant be far away from going human to human. (may already be doing so) This variant was discovered in the South of China around the same time Hong Kong had its first case. Remember the reaction the Hong Kong government took!!! I thought at the time it was over the top. It was an over reaction. Maybe it wasn't and they knew about this new strain?? Abstract: An avian-origin human-infecting influenza (H7N9) virus was recently identified in China. We have evaluated the viral hemagglutinin (HA) receptor–binding properties of two human H7N9 isolates, A/Shanghai/1/2013 (SH-H7N9) (containing the avian-signature residue Gln226) and A/Anhui/1/2013 (AH-H7N9) (containing the mammalian-signature residue Leu226). We found that SH-H7N9 HA preferentially binds the avian receptor analog, whereas AH-H7N9 HA binds both avian and human receptor analogs. Furthermore, an AH-H7N9 mutant HA (Leu226 → Gln) was found to exhibit dual receptor-binding property, indicating that other amino acid substitutions contribute to the receptor-binding switch. The structures of SH-H7N9 HA, AH-H7N9 HA, and its mutant in complex with either avian or human receptor analogs show how AH-H7N9 can bind human receptors while still retaining the avian receptor–binding property
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jacksdad
Executive Admin Joined: September 08 2007 Location: San Diego Status: Offline Points: 47251 |
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Cobber - I'm always supposed to be doing something else when I'm here.
Funny you should post this because I was going add to something I wrote earlier in this thread but got busy and cut it short. I was going to make a comment about whether they're seeing distinct changes that we should worry about between the original Shanghai virus and any of the strains popping up in other regions, specifically in the south. Pretty much answered that one for me And you're right. It would explain why Hong Kong has been on higher alert of late. |
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"Buy it cheap. Stack it deep"
"Any community that fails to prepare, with the expectation that the federal government will come to the rescue, will be tragically wrong." Michael Leavitt, HHS Secretary. |
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