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Tracking the next pandemic: Avian Flu Talk

H3N3-flu

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Dutch Josh View Drop Down
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    Posted: November 28 2023 at 3:55am

[url]https://afludiary.blogspot.com/2023/11/emerg-microb-inf-emergence-of-novel.html[/url] or https://afludiary.blogspot.com/2023/11/emerg-microb-inf-emergence-of-novel.html ;

Emerg. Microb & Inf.: Emergence of Novel Reassortant H3N3 Avian Influenza viruses, China 2023

DJ, H3N3 is NOT new ! [url]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC516286/[/url] or https://www.ncbi.nlm.nih.gov/pmc/articles/PMC516286/ ;

H3N3 and H1N1 influenza A viruses were isolated from Canadian pigs in 2001 and 2002. These viruses are phylogenetically related to waterfowl viruses and antigenically distinct from reference swine influenza viruses. The isolation of these viruses reemphasizes the potential for interspecies transmission of influenza viruses from waterfowl to pigs in North America.

Back to flu diary;

While we watch the global spread, and occasional spillover into humans, of HPAI H5Nx viruses with with understandable concern, all of the known influenza pandemics - going back 130 years - have come from H1, H2, or H3 influenza viruses (see ECDC graphic above). 

That doesn't mean that an H5 (or H7, H9, H10, etc.) virus couldn't spark a human flu pandemic, only that we haven't seen that happen during our relatively short span (80 years) of being able to identify influenza subtypes.  

And as we've discussed previously (see Are Influenza Pandemic Viruses Members Of An Exclusive Club?), novel H1, H2, and H3 flu viruses appear to have fewer barriers to overcome in order to jump to humans - and while they may not prove as virulent as H5 & H7 avian subtypes - that puts them at or near the top of our pandemic threats list.

Twice in my lifetime (1957 and 1968) avian flu viruses have reassorted with seasonal flu and launched a human pandemic.

  • The first (1957) was H2N2, which According to the CDC `. . . was comprised of three different genes from an H2N2 virus that originated from an avian influenza A virus, including the H2 hemagglutinin and the N2 neuraminidase genes.'
  • In 1968 an avian H3N2 virus emerged (a reassortment of 2 genes from a low path avian influenza H3 virus, and 6 genes from H2N2which supplanted H2N2 - killed more than a million people during its first year - and continues to spark yearly epidemics more than 50 years later.

DJ, See [url]https://en.wikipedia.org/wiki/Hong_Kong_flu[/url] or https://en.wikipedia.org/wiki/Hong_Kong_flu for 1968,

"Asian Flu" [url]https://en.wikipedia.org/wiki/1957%E2%80%931958_influenza_pandemic[/url] or https://en.wikipedia.org/wiki/1957%E2%80%931958_influenza_pandemic 

Note: The 2009 H1N1 pandemic - although it was a triple-reassortment containing some avian-origin genetic contributions - emerged from swine. 

While a novel pandemic virus might emerge solely from the wild, the `easier' route would be for an avian or swine virus to reassort with an already `human-adapted' seasonal flu virus, and produce a pandemic inducing hybrid. 

This is the reason why yearly flu vaccination is strongly recommended for people who raise pigs, or work with poultry.

Over the past couple of years we've seen a steady parade of scientific reports coming out of China describing new H3 avian viruses (see EID Journal: Evolution of Avian Influenza Virus (H3) with Spillover into Humans, China), which includes H3N8 which has spilled over into humans at least 3 times, and a Novel Reassortant H3N6 Canine Influenza Virus.)

Today we've another such report in a letter published in Emerging Microbes & Infections, which describes a new reassortant H3N3 virus which includes an HA gene from the H3N8 virus mentioned above, an NA gene from H10N3 (which has also spilled over into humans), and internal genes from H9N2 (which is also zoonotic).

Despite its impressive pedigree, this reassortant H3N3 virus is not yet pathogenic in mice, and still binds preferentially to avian receptor cells.   The authors note, however, that it has some concerning traits, describing:

Several mutations that would increase polymerase activity and replication ability and increased virulence in mammalian cell lines or mice were identified, including I292V, I504V and A588V in PB2 and K356R in PA. Several mutations that would especially increase pathogenicity in chickens were identified, including K627E in PB2, I127V, I550L and F672L in PA, P64S and l69P in M2 and A42S and F103L in NS1 [12]. There was also a mutation of S31N in M2 which could increase the resistance to amantadine and rimantadine [13].

DJ, So the H3N3 in Canadian pigs from 2001, 2003 has a different background ? 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dutch Josh Quote  Post ReplyReply Direct Link To This Post Posted: November 28 2023 at 4:02am

Emergence of novel reassortant H3N3 avian influenza viruses with increased pathogenicity in chickens in 2023

Qiuyan Mao,Shuning Zhou,Shuo Liu,Cheng Peng,Xin Yin,Jinping Li, show all

Article: 2287683 | Accepted author version posted online: 22 Nov 2023

Dear editor,

(EXCERPT)

Since 2023, several large-scale egg farms in Jiangsu province in China have experienced cases of drops in food and water intake, with affected chickens showing respiratory signs including swelling of the sinuses and discharge from the eyes, nares, mouth, severe dyspnea and reduced egg production, with lower mortality rates. The trachea, lungs, liver, and intestines of dead chickens were collected and homogenized to extract DNA and RNA. The egg drop syndrome virus, AIV, Newcastle disease virus, infectious bronchitis virus, infectious bursitis virus and infectious laryngotracheitis virus were tested by real-time polymerase chain reaction methods (national or industry standards), with only AIV being positive. The H3N3 subtype was further identified using HA and NA specific primers [10] and sequencing. The viruses were isolated by inoculation into 10-day-old specific-pathogen-free (SPF) embryonated chicken eggs with homogenate and named A/chicken/Jiangsu/NT322/2023(H3N3) (NT322/H3N3) and A/chicken/Jiangsu/NT308/2023(H3N3) (NT308/H3N3), respectively. Throat and cloacal swabs of chickens from a nearby live poultry market were also sampled and one strain A/chicken/Jiangsu/J1247/2023(H3N3) was isolated.

To investigate the origins of these H3N3 isolates, their genomes were sequenced using Sanger sequencing and phylogenetic analysis was performed. The phylogenetic trees for each gene segment were generated by using the neighbor-joining method in the MEGA 11 package. The bootstrap value was calculated with 1000 replicates. The eight gene segment sequences of the three strains shared 99.5 to 100% nucleotide identity among them, suggesting they were highly homologous.

The HA genes of these viruses were highly homologous to those of H3N8 that caused the three human cases and shared 97.5 to 99.2% nucleotide identity between them (Figure 1(A)). Their NA genes were genetically close to those from H10N3 circulating in poultry in China and including the human case in 2021) in China (Figure 1(B)). The internal genes were genetically associated with the H9N2 circulating in chickens in China. 

The internal gene constellation was more similar to that of the human H10N3 isolate than that of the human H3N8 isolates, sharing 95.9 to 98.7% nucleotide homology with A/Jiangsu/428/2021(H10N3), except PA and M genes which were highly homologous with human H3N8 isolates at 98.8% and 99.5%, respectively.

(SNIP)

Discussion

This study presents a preliminary analysis of the isolation and characterization of novel reassortant H3N3 viruses from chickens, which have undergone frequent reassortment. Their HA and NA genes are genetically close to the human infected isolates, H3N8 and H10N3, respectively. Their internal genes are derived from the H9N2 circulating in chickens in China and are more similar to that of the human H10N3 isolate. Our surveillance suggested that H9N2 accounts for about 72% of the AIVs identified in Jiangsu province in 2023 and about 12.3% of birds in LBMs carry H9N2 viruses (unpublished data). 

Although these H3N3 viruses preferentially bind to avian-like receptors and were not pathogenic in mice, they were likely to possess molecular markers indicative of potential pathogenicity. Multiple human-infecting AIVs, such as H7N9, H10N8, and the recently emerging H3N8 and H10N3, have been proved to contain the internal genes of H9N2 viruses. Poultry that carry H9N2 AIVs provide a favourable environment for different subtypes of viruses to exchange their gene segments with H9N2 AIVs. Lesions caused by LPAIV, such as H9N2, are difficult to reproduce under experimental settings [14], but the H3N3 viruses isolated in this study exhibited similar clinical signs in SPF chickens as those in domestic production, indicating these H3N3 viruses have increased virulence, unlike the H3 virus in wild birds [15].

Although the H3 subtype is a low-pathogenic AIV subtype prevalent in domestic poultry, the emerging avian H3N3 virus from chicken flocks in China appears to exhibit an increasing pathogenicity. Close and continuous surveillance of the H3N3 subtype of AIVs circulating in poultry is required, their pathogenesis should be continuously investigated and their impact on the poultry industry in the future should be evaluated. Effective control measures including vaccination should also be established to reduce the prevalence and decrease the economic impact of the virus infection in poultry, similar to prevention measures for H9N2 infection.

DJ, Detection in China may NOT mean it started in China or is only a Chinese risk ! It is VERY WELCOME !!!! China is investigating and reporting on this -so far chicken-flu- H3N3 ! 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dutch Josh Quote  Post ReplyReply Direct Link To This Post Posted: November 28 2023 at 4:08am

Human links H10N3 and H3N8 flu types

[url]https://en.wikipedia.org/wiki/Influenza_A_virus_subtype_H10N3[/url] or https://en.wikipedia.org/wiki/Influenza_A_virus_subtype_H10N3 ;

Influenza A virus subtype H10N3 is a subtype of viruses that causes influenza (flu). It is mostly present in wild avian species. The first human case was reported in 2021.

In animals[edit]

Only around 160 cases of the virus have been reported in the 40 years before 2018, mostly in various waterfowl or wild birds.[1] Existing studies show that H10 influenza viruses are present in a wide range of domestic and wild avian species, as well as in mammals, showing potential for adaptation.[2] H10N3 has been isolated across a wide geographic distribution, including in species such as domestic poultry (chickens),[2] ducks,[3][4] other waterfowl, and terrestrial birds.[5] In animals, the viruses display a complex pathology, with complex reassortments and mutations contributing to pathobiology patterns in chickens, ducks and mice indicative of a possible threat to humans,[6] although H10N3 is usually a less severe strain and is unlikely to cause a significant outbreak.[1]

In humans[edit]

The first human case of H10N3 was reported in Zhenjiang, in China's eastern province of Jiangsu.[1][7] This index case was a patient admitted to the hospital with a fever and worsening respiratory symptoms on April 28, 2021, with a diagnosis of H10N3 confirmed in May 2021. None of the individual's close contacts developed any symptoms or signs of infection. The virus identified from this individual contains an HA cleavage site that is consistent with a "low pathogenicity avian influenza" (LPAI), and is also a reassortant strain, combining the HA and NA genes from H10N3 with internal genes from H9N2 viruses.[7]

According to China's National Health Commission (NHC), human cases of H10N3 have not been reported elsewhere in China.[8] There are no indications that the virus is easily transmissible among humans, with no confirmed cases of human-to-human transmission.[1][9] Other types of avian-origin H10 influenza have been reported in human beings, including in Egypt, Australia and China, highlighting a potential public health hazard, although none of the strains so far detected have shown signs of human transmission.[2][7]

and [url]https://en.wikipedia.org/wiki/Influenza_A_virus_subtype_H3N8[/url] or https://en.wikipedia.org/wiki/Influenza_A_virus_subtype_H3N8 ;

H3N8 is a subtype of the species Influenza A virus that is endemic in birds, horses and dogs. It is the main cause of equine influenza and is also known as equine influenza virus. In 2011, it was reported to have been found in seals.[1] Cats have been experimentally infected with the virus, leading to clinical signs, shedding of the virus and infection of other cats.[2] In 2022 and 2023, three people in China were infected with H3N8,[3] with one fatality, marking the first time a human has died from this strain of flu.[4]

DJ, since both the "basics" have (also) links to humans H3N3 could develop into a "more risky" variant. 

People are tired of CoViD and H3N3 symptoms may look a lot like both CoViD and other flu types...However later on it could show more risks. 

Flu Diary;

LPAI (Low pathogenic Avian Influenza) viruses have an advantage, in that they can more easily spread unnoticed in both commercial and backyard poultry, providing them with more opportunities to interact with humans and the influenza viruses we carry.  


The H7N9 virus that emerged in China in 2013 was also an LPAI - and while it did not visibility sicken chickens - it could cause severe and often fatal infection in humans.  

Whether H3N3 has the `right stuff' to pose a threat to humans is unknown at this time.  But it is another example of the rapid evolution of avian viruses in China, and a reminder of why we need to be prepared to meet whatever new challenges nature throws at us.  

No doubt we may hear more on H3N3

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dutch Josh Quote  Post ReplyReply Direct Link To This Post Posted: November 28 2023 at 9:55am

[url]https://flutrackers.com/forum/forum/welcome-to-the-scientific-library/surveillance-and-epidemic-control/817237-complete-genome-sequence-of-a-novel-reassortant-h3n3-avian-influenza-virus[/url] or https://flutrackers.com/forum/forum/welcome-to-the-scientific-library/surveillance-and-epidemic-control/817237-complete-genome-sequence-of-a-novel-reassortant-h3n3-avian-influenza-virus 

Complete genome sequence of a novel reassortant H3N3 avian influenza virus


Arch Virol. 2019 Aug 27. doi: 10.1007/s00705-019-04386-8. [Epub ahead of print]
Complete genome sequence of a novel reassortant H3N3 avian influenza virus.

-

Abstract

Aquatic birds are known to be a reservoir for the most common influenza A viruses (IAVs). In the annual surveillance program, we collected the feces of migratory birds for the detection of IAVs in South Korea in November 2016. A novel reassorted H3N3 avian influenza virus (AIV) containing genes from viruses of wild and domestic birds was identified and named A/aquatic bird/South Korea/sw006/2016(H3N3). The polymerase basic 2 (PB2) and non-structural (NS) genes of this isolate are most closely related to those of wild-bird-origin AIV, while the polymerase basic 1 (PB1), polymerase acidic (PA), hemagglutinin (HA), nucleoprotein (NP), neuraminidase (NA), and matrix (M) genes are most closely related to those of domestic-bird-origin AIV. A/aquatic bird/South Korea/sw006/2016 contains PA, NP, M, and NS genes were most closely related to those of AIV subtype H4 and PB2, PB1, and HA genes that are most closely related to those of AIV subtype H3N8, while the NA gene was most closely related to those of subtype H10, which was recently detected in humans in China. These results suggest that novel reassortment of AIV strains occurred due to interaction between wild and domestic birds. Hence, we emphasize the need for continued surveillance of avian influenza virus in bird populations.

DJ, H3N8 and H10N3 just like the latest finding in China

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dutch Josh Quote  Post ReplyReply Direct Link To This Post Posted: November 28 2023 at 10:09am

may 30 2015 Sri Lanka Human H3N3 case ?

[url]https://flutrackers.com/forum/forum/asia/seasonal-flu-2009-2014-including-h1n1-pandemic-2009-ab/sri-lanka/731449-sri-lanka-influenza-2015-75-deaths#post732188[/url] or https://flutrackers.com/forum/forum/asia/seasonal-flu-2009-2014-including-h1n1-pandemic-2009-ab/sri-lanka/731449-sri-lanka-influenza-2015-75-deaths#post732188 ;

Sentinel site surveillance of influenza
Epidemiology Unit, Sri Lanka conducts influenza sentinel sites surveillance at 19 selected hospitals in order to check the current circulating viral pattern. Surveillance is carried out for Influenza Like Illness (ILI) and Severe Acute Respiratory Infection (SARI). ILI is defined as an acute respiratory illness with measured temperature 38 0 C or more and cough, with onset within the past ten days. SARI is defined as requiring hospitalization in addition to the features of ILI (WHO 2014). Samples of nasopharyngeal aspirates are collected up to 10 per month from ILI patients and up to 05 per month from SARI patients.
Of the 111 ILI samples collected during March 2015, 07 samples were positive for influenza A (influenza A H1N1 – 05, influenza A H3N2 01, un-typed – 01) and 11 samples were positive for influenza B. Among the 19 SARI samples received during March 2015, 01 has been positive for influenza A H3N3.
It was noted that from March 2015 to April 2015, the number of total SARI patients reported has increased by about 1%.
Last Updated on Wednesday, 27 May 2015 04:29
http://www.epid.gov.lk/web/index.php...public&lang=en

DJ...maybe more H3N3 human cases ????

[url]https://flutrackers.com/forum/search?r=62780504&p=2[/url] or https://flutrackers.com/forum/search?r=62780504&p=2 (Mexico)

tetano
Re: Queretaro registers 30 deaths from influenza

Queretaro reported 32 deaths from influenza in the year

The holder of the Secretary of Health, the state, Mario Cesar Garcia Feregrino reported that it has increased to 32 the number of deaths in the entity because of the influenza, of which 24 are of a(H1N1). Interviewed after the Seguro Popular in Queretaro received the ISO-9001, the state official i think that this is not a question of an alarming figure, since the vaccination campaign has met all their objectives. He said that of the 32 reported cases, 24 are of a(H1N1), two more by A(H3N3) and the rest has not been criminalized, while there are 211 positive cases in the state health services. The cases of patients with influenza A virus Iran to the low to the extent that it increases the environmental temperature and, therefore, they will be less cases of deaths.

Seals...[url]https://flutrackers.com/forum/search?q=h3n3&searchJSON=%7B%22keywords%22%3A%22h3n3%22%7D[/url] or https://flutrackers.com/forum/search?q=h3n3&searchJSON=%7B%22keywords%22%3A%22h3n3%22%7D 

Re: Denmark and Germany: Seal Deaths Caused by Bird Flu? - H10N7 detected

A GenBank search shows past seal influenza infections from: H1N1, H3N3, H3N8, H4N5, H4N6, and H7N7.

Given this newest infections, seals carry a somewhat diverse set of influenza strains. I wonder which animals, except wild birds, carry the most configurations?

DJ...the more species can carry a virus the more variants may show up...

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Post Options Post Options   Thanks (0) Thanks(0)   Quote roni3470 Quote  Post ReplyReply Direct Link To This Post Posted: November 28 2023 at 8:22pm

Dutch, can you summarize what is going on/what you think is going on instead of just all these articles?

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dutch Josh Quote  Post ReplyReply Direct Link To This Post Posted: November 28 2023 at 8:42pm

Roni, I get your question !

Via the articles I am trying to figure out if H3N3 in chicken in China (and likely other places) is "the next flu pandemic"...

The H3N3 detected is made up of two human components; H3N8 and H10N3 -both so far limited risks. 

H3N3 in itself is not new, found in several species. However maybe H3N3 made up from human flu virus may be new...

Again...I am just trying to make my mind up...

The large scale disease outbreak in children in China (etc) is NOT related to H3N3...

Does that answer your point ?

I may find more stories-H1,H2,H3 flu-types are high risk for humans...However earlier detection of H3N3 remained limited. 

So I may post more parts from articles just to get a view...

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Post Options Post Options   Thanks (0) Thanks(0)   Quote roni3470 Quote  Post ReplyReply Direct Link To This Post Posted: November 29 2023 at 8:33am

Yes, it does and thank you!  I am trying to make all those same determinations!  I do love your articles but I also just like it when you give your opinion and/or summaries so when I am in a rush I can see what the topics are all about!  Thank you!

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dutch Josh Quote  Post ReplyReply Direct Link To This Post Posted: November 29 2023 at 10:44am

Just a reminder-I am not an expert...just (also) trying to make my mind up...

Thanks for the welcome comment...H3N3 may develop to become a major problem...or not...

The major risk may be less immunity and co-infections...

Stay safe & sane !

[url]https://flutrackers.com/forum/forum/china-other-health-threats/china-pneumonia-respiratory-and-influenza-like-illnesses-ili/982359-china-pediatric-hospitals-full-with-seasonal-flu-mycoplasma-pneumonia-patients-guangzhou-guangdong-province-november-27-2023[/url] or https://flutrackers.com/forum/forum/china-other-health-threats/china-pneumonia-respiratory-and-influenza-like-illnesses-ili/982359-china-pediatric-hospitals-full-with-seasonal-flu-mycoplasma-pneumonia-patients-guangzhou-guangdong-province-november-27-2023 

In the clinic of Wu Zhu, head of the pediatric outpatient and emergency department of Zhujiang Hospital of Southern Medical University, the number of patients is also running at a high level. According to his recent observations, the number of children infected with Mycoplasma pneumoniae has declined, while influenza is on the rise, with influenza B being the dominant category.

So B-flu...in [url]https://en.wikipedia.org/wiki/Guangdong[/url] or https://en.wikipedia.org/wiki/Guangdong ;

Guangdong (UK/ɡwæŋˈdʊŋ/US/ɡwɑːŋ-/),[6] formerly romanized as Canton or Kwangtung, is a coastal province located in South China, on the north shore of the South China Sea.[7] The provincial capital is Guangzhou. With a population of 126.84 million (as of 2021)[4] across a total area of about 179,800 km2 (69,400 sq mi),[1] Guangdong is the most populous province of China and the 15th-largest by area as well as the second-most populous country subdivision in the world.

Mega-cities, high rise buildings may be part of the problem..

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dutch Josh Quote  Post ReplyReply Direct Link To This Post Posted: December 07 2023 at 9:19pm

[url]https://afludiary.blogspot.com/2023/12/frontiers-microbiology-chinas-growing.html[/url] or https://afludiary.blogspot.com/2023/12/frontiers-microbiology-chinas-growing.html ;

The emergence of a novel H3N8 virus last year in China, which has not only spread widely in wild birds and poultry, but has also spilled over into humans (see herehere, and here), has helped to propel H3 viruses back into the limelight.

All of which brings us to a review article, published today in Frontiers in Microbiology, that looks at growing concerns over the spread and evolution of H3Nx viruses in China.  


This is a lengthy review, so I've only posted some excerpts. Follow the link to read it in its entirety. I'll have a brief postscript after the break. 

-

The H3-subtype of avian influenza virus (AIV) is one of the most frequently detected low pathogenic avian influenza virus (LPAIV) subtypes in birds and fowls, causing substantial economic loss to the poultry industry. Most importantly, besides poultry, mammals could also be infected with it, such as swines, canines, equines, felines, and humans, posing a serious public health threat. This allows the virus to persist widely in poultry and wild birds for a long time, where it may mix with other subtypes, providing conditions for viral recombination or reassortment.

Currently, the monitoring of H3-subtype AIV is inadequate, and there is a lack of effective prevention and control measures for H3-subtype AIV.

-

6 Conclusion

H3-subtype AIV is in a state of evolution and recombination. Frequent recombination occurred between different subtypes, and cross-species transmission occurred. Moreover, multiple mammalian adaptive mutation sites were found on H3-subtype AIV HA protein.
These findings indicate that H3-subtype AIV is gradually adapting to mammals and even humans. Therefore, the monitoring of mutation and recombination in H3-subtype AIVs should be continued, and efficient vaccines should be developed to prevent and control the prevalence of H3-subtype AIV. 

 

While 1968 was the first time that an H3 virus was confirmed to have sparked a human influenza pandemic, we know very little about the viruses that circulated prior to the 1918 H1N1 pandemic virus, and some researchers have suggested than H3N8 may have emerged in the 1890s.

The limited flow of information out of China makes it difficult to fully access the risks, but it would not be terribly surprising to see H3N8 added to this list at some point. New genotypes can emerge at anytime, so there are a lot of possibilities.


While an H5Nx pandemic could easily be more severe, H3 viruses have proven their ability to cause significant morbidity and mortality, and should not be underestimated.

DJ, We simply do not know much of most diseases...Lots of disease in humans may be missed-non-human disease often only is "interesting" for economic reasons. So we may be surprised...

Flu-types prior to 1900 -even if it was widespread in humans-also are a big question mark. It may have been earlier variants of CoViD (Russian Flu 1890, however there was also a "major" flu in 1880 ? [url]https://www.cdc.gov/flu/avianflu/timeline/avian-timeline-1880-1959.htm[/url] or https://www.cdc.gov/flu/avianflu/timeline/avian-timeline-1880-1959.htm )

A third factor is circumstances; World War One made the Spanish Flu into a massive killer. CoViD in the present also may see a major "opening"...for H3N3, H3N8 ???

We cannot solve our problems with the same thinking we used when we created them.
~Albert Einstein
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