#h3n8 — Public Fediverse posts

From #Surfaces to #Spillover: Environmental #Persistence and Indirect #Transmission of #Influenza #H3N8 Virus, https://etidiohnew.blogspot.com/2025/12/from-surfaces-to-spillover.html

Preplanned Studies: #Phylogenetic and #Molecular Characteristics of An #H3N8 Avian #Influenza Virus Detected in Wild #Birds — #Beijing, #China, September 2024, https://etidiohnew.blogspot.com/2025/11/preplanned-studies-phylogenetic-and.html

Structural basis of #receptor-binding #adaptation of #human-infecting #H3N8 #influenza A virus, https://etidiohnew.blogspot.com/2025/02/structural-basis-of-receptor-binding.html

An emerging #PB2-627 #polymorphism increases #pandemic #potential of avian #influenza virus by breaking through ANP32 host restriction in #mammalian & avian hosts, BioRxIV: https://www.biorxiv.org/content/10.1101/2024.07.03.601996v4

by screening the global PB2 seq., we discovered a new independent cluster with PB2-627V emerged in the '10s, which is prevalent in various avian, mammalian, & human isolates of AIVs, including #H9N2, #H7N9, #H3N8, 2.3.4.4b #H5N1, and other subtypes.

An emerging #PB2-627 #polymorphism increases the #pandemic #potential of avian #influenza virus by breaking through ANP32 #host #restriction in #mammalian and avian hosts, BioRxIV: https://www.biorxiv.org/content/10.1101/2024.07.03.601996v3

...we discovered a new independent #cluster with PB2-627V emerged in the 2010s, which is prevalent in various avian, mammalian, and human isolates of AIVs, including #H9N2, #H7N9, #H3N8, 2.3.4.4b #H5N1, and other subtypes.

Large-Scale #Serological #Survey of #Influenza A Virus in South #Korean Wild #Boar (Sus scrofa) https://pubmed.ncbi.nlm.nih.gov/38842623/?utm_source=Feedly&utm_medium=rss&utm_campaign=None&utm_content=1fgJURi2yzLesFml6et0Bb6krzs_FrNIYgPYVFN50JPwVNFg9s&fc=None&ff=20240606155644&v=2.18.0.post9+e462414

Detected subtypes included 23 cases of pandemic 2009 #H1N1, six of human seasonal #H3N2, three of classical swine H1N1, 13 of triple-reassortant swine #H1N2, seven of triple-reassortant swine H3N2, and seven of swine-origin H3N2 variant. Notably, none of the serum samples tested positive for avian IAV subtypes #H3N8, #H5N3, #H7N7, and #H9N2 or canine IAV subtype H3N2.

Avian #Influenza Virus and Avian #Paramyxoviruses in Wild #Waterfowl of the Western Coast of the #Caspian Sea (2017–2020), Viruses: https://www.mdpi.com/1999-4915/16/4/598

The following subtypes were determined and whole-genome nucleotide sequences of the isolated strains were obtained: #H1N1 (n = 2), #H3N8 (n = 8), #H4N6 (n = 2), #H7N3 (n = 2), #H8N4 (n = 1), #H10N5 (n = 1), and #H12N5 (n = 1). No high pathogenicity influenza virus H5 subtype was detected.

#Molecular Characterization of Non- #H5 and Non- #H7 Avian #Influenza Viruses from Non-Mallard #Migratory #Waterbirds of the North #American #Flyways, 2006–2011, Pathogens: https://www.mdpi.com/2076-0817/13/4/333

The most common H and N combinations were #H3N8 (23.0%), #H4N6 (18.4%), and #H4N8 (18.4%). The HA gene between non-mallard and mallard MW isolates during the same time period shared 85.5–99.5% H3 identity and 89.3–99.7% H4 identity.

High-pathogenicity avian influenza in wildlife:
a changing disease dynamic that is expanding
in wild birds and having an increasing impact
on a growing number of mammals

#H1N1 #H3N8 #avian_influenza #IAV

https://avmajournals.avma.org/view/journals/javma/aop/javma.24.01.0053/javma.24.01.0053.xml

#Surveillance and #Genetic Analysis of LP Avian #Influenza Viruses Isolated from #Feces of Wild #Birds in #Mongolia, 2021 to 2023, Animals (Basel), https://www.mdpi.com/2076-2615/14/7/1105

Prevalence of AIVs in wildbirds was 1.01%, with a total of 77 AIVs isolated during these 3 years. These 77 AIVs included HA subtypes H1, H2, H3, H4, H6, H10 and H13 and neuraminidase (NA) subtypes N1, N2, N3, N6, N7 and N8. The most frequently detected subtype combinations were #H3N8 (39.0%) and #H4N6 (19.5%)...

Avian #Influenza Virus and Avian #Paramyxoviruses in Wild #Waterfowl of the Western Coast of the #Caspian Sea (2017–2020), Viruses: https://www.mdpi.com/1999-4915/16/4/598

The following subtypes were determined and whole-genome nucleotide sequences of the isolated strains were obtained: #H1N1 (n = 2), #H3N8 (n = 8), #H4N6 (n = 2), #H7N3 (n = 2), #H8N4 (n = 1), #H10N5 (n = 1), and #H12N5 (n = 1). No high pathogenicity influenza virus H5 subtype was detected.

#Genetic and #virological characteristics of a #reassortant avian #influenza A #H6N1 virus isolated from wild #birds at a live-bird #market in #Egypt, Arch Virol.: https://link.springer.com/article/10.1007/s00705-024-06022-6

Phylogenetic analysis indicated that the Egyptian H6N1 strain A/Garganey/Egypt/20869C/2022(H6N1) has a unique genomic #constellation, with gene #segments inherited from different subtypes (#H5N1, #H3N8, #H7N3, H6N1, and #H10N1) that have been detected previously in AIVs from Egypt and some Eurasian countries.

#Characterization of a #human #H3N8 #influenza virus https://pubmed.ncbi.nlm.nih.gov/38408394/?utm_source=Feedly&utm_medium=rss&utm_campaign=None&utm_content=1fgJURi2yzLesFml6et0Bb6krzs_FrNIYgPYVFN50JPwVNFg9s&fc=None&ff=20240226201417&v=2.18.0.post9+e462414

-- INTERPRETATION: Our data demonstrate that reverse genetics-generated A/Henan/2022 virus is a low pathogenic influenza virus (of #avian influenza virus descent) with some #antigenic resemblance to older human #H3N2 viruses and limited respiratory #droplet #transmissibility in #ferrets.

''Our experimental studies showed that these #H3N8 viruses were transmissible in #ferrets, and #serological data suggest that the #human population lacks effective immunological protection against it. With its wide geographical distribution and continuing evolution in chickens, other spillovers to humans can be expected and might lead to more efficient transmission in humans.''

#H3N8 #bird #flu has never been detected in the United States in people.

However, H3N8 viruses of a different genetic lineage have been detected in U.S. wild birds and some mammals in the past.

In 2011, there was an outbreak of H3N8 viruses among harbor seals in New England that caused deaths in 162 seals.

In the United States, current bird flu preparedness and surveillance activities are largely focused on #H5N1 bird flu, which is widespread in U.S. wild birds and has caused extensive outbreaks in U.S. poultry, with sporadic spillover to some mammals.

The current risk to the U.S. general public from H5N1 bird flu viruses remains low at this time; however, it is important to remember that #risk #depends on #exposure.
People with more exposure might have a greater risk of infection.

#CDC has guidance for specific groups of people with exposure to poultry, including poultry workers and people responding to outbreaks of avian influenza A(H5N1) in poultry.

Additional information on protective actions around birds, including what to do if you find a dead bird, is available as well.

https://www.cdc.gov/flu/avianflu/spotlights/2022-2023/avian-influenza-h3n8-china.htm