H7N9 virus mutant was found in human cases from China - possibly more pathogenic in chickens

[tetano]

　　Guangzhou, 19 Feb (Xinhua) - In January 2017, the Center conducted a gene sequencing analysis of the virus isolated from H7N9 cases in two cases, and found that in the case of the disease, Two strains of the hemagglutinin linked to the peptide position of the gene insertion mutation, suggesting that the virus mutation to the highly pathogenic virus against birds.
　　
Guangdong Provincial Center for Disease Control and Prevention experts to judge and communicate with the relevant experts in the agricultural sector that, according to the results of the virus sequence analysis, the virus has not yet appeared on the human infection, virulence and interpersonal ability to enhance the mutation. Two cases of disease before the incidence of bird exposure history, and in its exposure to poultry birds have occurred in the phenomenon of death. At present, a case has been cured, another case is still in treatment. All the 105 cases of close contact after two weeks of medical observation, were not fever, cough and other symptoms.

H7N9 virus is a influenza virus, one of its main features is prone to gene reassignment and mutation. Some mutations may lead to the virus on the human appeal, virulence and interpersonal communication capacity enhancement, so the virus mutation has been widely concerned at home and abroad. It is understood that the agricultural sector laboratory also from Guangdong, four poultry specimens found similar to the variation of the virus. China Healthcare System will work with the agricultural sector to jointly study the source and scope of the variability virus and continue to strengthen the monitoring of the H7N9 virus and discover any possible variability. The results have been communicated to the World Health Organization. (Finish)

http://www.qhnews.com/newscenter/system/2017/02/19/012246311.shtml

[tetano]

Guangdong discovers variant of H7N9 virus from human infection cases

The disease control and prevention center of south China's Guangdong Province announced on Sunday that it has found variant of H7N9 virus from human infection.

The Guangdong Provincial Center for Disease Control and Prevention said on its website that it discovered gene mutation in H7N9 virus from two human cases in January.

The variant is highly pathogenic among poultry, but not among humans, said the website.

The two human cases were both exposed to poultry. One was cured, while the other is still being treated, and none of the 105 people who had close contact with them has shown signs of infection, the website said.

China's health departments will continue to work with the agricultural departments to do researches involving sources and influence scope of the H7N9 variant, and strengthen monitoring of the virus, according to the website.

China has notified discovery of the H7N9 variant to the World Health Organization.

http://newscontent.cctv.com/NewJsp/news.jsp?fileId=396741

[sharon sanders]

Guangdong CDC: Two H7N9 `Variants' Isolated From Human Cases

Credit NIAID

#12,239


Throughout its relatively short (4 year) reign, we've watched H7N9's evolution closely for signs that it might be evolving into a more dangerous pathogen. During that time we've seen its genetic diversity grow rapidly through continual reassortment with other avian viruses (particularly H9N2), antigenic drift, and its passage through a variety of host species.

A process dubbed `genetic tuning’ by the authors of a paper that appeared inEurosurveillance back in 2014 (seeGenetic Tuning Of Avian H7N9 During Interspecies Transmission).

With this diversity we've also seen some subtle (sometimes regional) changes in H7N9's behavior, something which was the topic of last December's MMWR: Assessing The 4th Epidemic Wave Of H7N9 In China, where researchers warned of `the continued geographic spread, identification of novel reassortant viruses, and pandemic potential of the virus' - stating that `using the Influenza Risk Assessment Tool (10), CDC found that A(H7N9) virus has the highest potential pandemic risk of any novel influenza A viruses that have been assessed.'

But the two constants with H7N9 until now have been its low pathogenicity in birds and its lack of sustained transmission in humans.

Today we've a brief announcement from Guangdong's CDC that two virus samples collected from human hosts last month suggest one of those constants may be changing; its pathogenicity in birds.

While the ultimate significance and impact of this discovery remains unclear, this is another sign that the H7N9 virus continues to evolve in unexpected ways. First the (translated) announcement, then I'll be back with a bit more.

H7N9 virus mutant was found in human cases from China

Release Date: 2017-02-19 Views: Contributed by: Information Department of Publicity: Office Font: Big Middle Small

In January 2017, Guangdong Provincial Center for Disease Control and Disease on the two cases of human infection H7N9 cases were isolated virus gene sequencing analysis, found in the two strains of hemagglutinin link peptide position of the gene insertion mutation occurred, the test results Has been confirmed by the National Center for Viral Disease National Influenza Center.

I center experts to judge and communicate with the relevant experts in the agricultural sector that H7N9 virus in the hemagglutinin link peptide position of the gene insertion mutation, suggesting that the virus mutation to the highly pathogenic virus against birds; the second is based on the virus Sequence analysis results have not yet appeared in the mutant virus that has increased resistance to human infectivity, virulence and interpersonal communication.

Two cases of disease before the incidence of bird exposure history, and in the exposure of poultry birds have occurred in the phenomenon of death. At present, a case has been cured, another case is still in treatment. All the 105 cases of close contact after two weeks of medical observation, were not fever, cough and other symptoms.

H7N9 virus is a influenza virus, one of its main features is prone to gene reassignment and mutation. Some mutations may lead to the virus on the human appeal, virulence and interpersonal communication ability enhancement, so the virus variation has been widely concerned about the domestic and foreign.

It is understood that the agricultural sector laboratory also from Guangdong, four poultry specimens found similar to the variation of the virus. China's health care system will work together with the agricultural sector, the common source of the virus, the scope of the impact of in-depth study, and continue to strengthen the monitoring of H7N9 virus, in time to find any possible variation.

The results have been communicated to the World Health Organization.

China Center for Disease Control and Prevention

Although capable of causing serious (even fatal) illness in humans, H7N9 has - at least until now - been strictly an LPAI (Low Pathogenic Avian Influenza) virus in birds. As such, it has been very difficult to identify and contain in domesticated or wild bird populations.

A change to an HPAI virus might make identification in poultry flocks easier (potentially a good thing) - but could also serve as an evolutionary `bridge' to other changes; changes that might negatively impact how it behaves in mammalian hosts.

Admittedly, I've employed a lot of `weasel words' here, since we simply don't know where this new fork in H7N9's evolutionary road will lead. The fact that it has been detected in both humans and poultry in Guangdong Province, however, suggests it isn't just some `spontaneous' dead end mutation.

But until we learn more we won't know how biologically `fit' these variants really are.

Interestingly, on Friday Science Magazine ran a story (see Bird flu strain taking a toll on humans) with an interview with renown virologist Dr. Guan Yi from the University of Hong Kong, which seems to have telegraphed this discovery.

"It is too late to contain the virus in poultry," Guan says. He predicts that the virus will continue to spread in China's farms, possibly evolving into a strain that would be pathogenic for poultry. Authorities have culled more than 175,000 birds this winter to stamp out local outbreaks of H7N9 and other avian flu strains. Further spread of H7N9 "will naturally increase human infection cases," Guan says.

While today's announcement doesn't necessarily move H7N9 closer to becoming a pandemic strain, it is a reminder how labile and unpredictable influenza viruses can be.

Stay tuned.

Posted by Michael Coston at 6:45 AM

[Pathfinder]

Mutation of H7N9 bird flu strain found in Guangdong patients

Samples taken from patients show genetic change but no sign of higher risk to humans

PUBLISHED : Monday, 20 February, 2017, 11:40pm
UPDATED : Tuesday, 21 February, 2017, 2:45am
...
The Chinese Centre for Disease Control and Prevention ?informed the World Health Organisation that the mutation was found in samples collected from two patients in Guangdong province last month.

The mutation suggested the virus had become deadlier to poultry but there was no indication it posed a greater risk to people, or made transmission among humans more likely, the centre said in a statement released on Sunday.
...
Both patients had been exposed to dead poultry. One had been discharged while the other was still receiving treatment.
...
The centre said 105 people who were in close contact with the patients were being monitored, but none had developed symptoms of bird flu.

Agricultural authorities had also found four poultry samples that might contain the mutation but further study was necessary. The poultry samples were also collected in Guangdong.

Shi Yi, viral infection researcher at the Chinese Academy of Sciences? Institute of Microbiology, said mutations in bird flu were not uncommon, and the H5N1 virus had undergone a similar change.

?There is no laboratory experiment yet, but based on previous studies on H5N1, it?s possible for the mutated H7N9 to become more [likely to cause disease],? Shi said.

?But there is no proof to suggest any viral changes in existing infection channels or strength.?

...

http://www.scmp.com/news/china/society/article/2072454/mutation-h7n9-bird-flu-strain-found-guangdong-patients

[Pathfinder]

Tue Feb 21, 2017 | 1:10pm EST

China reports more severe form of bird flu, threat to poultry: WHO

By Stephanie Nebehay | GENEVA

China has detected an evolution in the H7N9 avian flu virus that is capable of causing severe disease in poultry and requires close monitoring, the World Health Organization (WHO) said on Tuesday.

Samples of the virus taken from two infected humans were injected into birds in a laboratory and became "highly pathogenic" for poultry, it said.

But that designation applies only to birds, not humans, WHO spokesman Christian Lindmeier said, and there is "no evidence that the changes in the virus affect the virus' ability to spread between humans."
...
The evolution of the virus may mean that the disease will become more apparent in some flocks, if birds begin to die off, making detection and control easier.

"This is the first time these changes have been detected. These are the only two cases in Guangdong province, China. So far, there have been no reports if similar changes have occurred elsewhere," Lindmeier said.
...

http://www.reuters.com/article/us-health-birdflu-china-who-idUSKBN16029T

------------------------------------------
See also:

China - 1 new outbreak of highly pathogenic avian influenza H7N9 in birds in markets in Guangdong (OIE, February 18, 2017)

https://flutrackers.com/forum/forum/china-h7n9-outbreak-tracking/china-h7n9-tracking-guangdong/771106-china-1-new-outbreak-of-highly-pathogenic-avian-influenza-h7n9-in-birds-in-markets-in-guangdong-oie-february-18-2017

[Pathfinder]

Translation Google

Land H7N9 mutant strains appear drug resistant do not buy live poultry

Time: 2017/02/26 12:29Latest update: 2017/02/26 12:50Word Level: Font level is reducedZoom in size

(Reuters) - Chinese Academy of Engineering, famous economist Zhong Nanshan said yesterday that two cases of H7N9 avian influenza virus mutation in Guangdong, China, drug resistance in the emergence of highly pathogenic birds, and now do not buy live birds.

Southern Metropolis Daily reported today at the 13th session of the International Association of Virology, Zhong Nanshan, an interview with reporters, said the recent discovery of two strains of mutants in the birds appear highly pathogenic, according to the present situation, The most critical is to prevent, prevent and control, from the source to solve. Do not do live poultry trade, but also to persuade the public not to buy live birds.

Zhong Nanshan said that the variation of the virus strain is not more toxic to people, or have a higher lethality, and is not in the crowd have a higher transmission rate, and now there is no accurate conclusion.

Zhong Nanshan said that this mutation has two characteristics: First, the original H7N9 is low pathogenicity, before H7N9 in poultry is not the disease, mainly to cause human disease. And the virus after the mutation will make the incidence of poultry, and was highly pathogenic characteristics.

Second, there are cases of resistance to Tamiflu (antiviral drugs), recently found in Guangdong, 2 cases of blood inside the patient, upper and lower respiratory tract variant of the virus, and resistance to Tamiflu.

He said that it is worth noting that the epidemic in mainland China this year, there are two characteristics: First, the number of patients in January than in January last year, a significant increase; the other is a report of the provinces than ever before.

Guangdong Province, the Center for Disease Control and Prevention in January this year, two cases of human infection H7N9 cases were isolated virus gene sequencing analysis, found two strains of gene insertion mutation. February 19, the test results have been mainland China CDC virus disease National Influenza Center review confirmed. 1060226

http://www.cna.com.tw/news/acn/201702260098-1.aspx