#h1n1pdm09 — Public Fediverse posts on home.social

Structural basis of broad #protection against #influenza virus by a #human #antibody targeting the #neuraminidase active site via a recurring motif in CDR H3

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.11.26.625467v1

Abstract
Influenza viruses evolve rapidly, driving seasonal epidemics and posing global pandemic threats. While neuraminidase (NA) has emerged as a vaccine target, shared molecular features of NA antibody responses are still not well understood. Here, we describe cryo-electron microscopy structures of the broadly protective human antibody DA03E17, which was previously identified from an H1N1-infected donor, in complex with NA from A/H1N1, A/H3N2, and B/Victoria-lineage viruses. DA03E17 targets the highly conserved NA active site using its long CDR H3, which features a DR (Asp-Arg) motif that engages catalytic residues and mimics sialic acid interactions. We further demonstrate that this motif is conserved among several NA active site-targeting antibodies, indicating a common receptor mimicry strategy. We also identified potential antibody precursors containing this DR motif in all donors of a healthy human donor BCR database, highlighting the prevalence of this motif and its potential as vaccine targeting. Our findings reveal shared molecular features in NA active site-targeting antibodies, offering insights for NA-based universal influenza vaccine design.

____

#aH3n2 #abstract #biology #h1n1pdm09 #health #immunology #influenzaA #monoclonalAntibodies #research #vaccine

#ah3n2 #abstract #biology #h1n1pdm09 #health #immunology

ETIDIoH @[email protected] · 2024-11-22 · 16:55 UTC

13th #Meeting of #WHO Expert Working #Group on #Surveillance of #Antiviral Susceptibility of #Influenza Viruses for WHO #GISRS

Source: World Health Organization, Weekly Epidemiological Record: https://www.who.int/publications/journals/weekly-epidemiological-record

{Excerpt, edited}

Executive summary

The WHO Expert Working Group on Surveillance of Influenza Antiviral Susceptibility (AVWG) supports the WHO Global Influenza Surveillance and Response System (GISRS) by providing practical guidance for monitoring the antiviral susceptibility of seasonal and emerging influenza viruses The 13th WHO AVWG meeting was held in hybrid format (faceto-face and virtually) on 13–14 June 2024 in Lyon, France.

Update on susceptibility of seasonal influenza viruses to approved antiviral agents

Between May 2023 and May 2024, WHO collaborating centres (CCs) and participating national influenza centres (NICs) reported that seasonal influenza activity in various regions had resumed to levels before the coronavirus disease 2019 (COVID-19) pandemic. Co-circulation of A(H1N1)pdm09, A(H3N2) and influenza B/Victoria lineage viruses was detected in most regions. Overall, influenza A and B viruses with reduced inhibition (RI) or highly reduced inhibition (HRI) to neuraminidase (NA) inhibitors (NAIs) were detected at low frequency. The most frequently identified substitution associated with RI or HRI by NAIs was NA-H275Y in A(H1N1)pdm09 viruses, which was detected at <2%. Double amino acid substitutions (NA-I223V+ NA-S247N) in A(H1N1)pdm09 viruses (referred to as dual mutant viruses) that resulted in RI by oseltamivir were first detected in May 2023 and spread rapidly to several regions of the world.{1,2} Influenza A and B viruses with amino acid substitutions in the polymerase acidic (PA) protein associated with reduced susceptibility to endonuclease inhibitor (baloxavir) were detected at low frequency. The PA-I38X (including I38T, I38N, I38M and I38V) amino acid substitution being the most frequently reported, but the overall detection frequency has remained low (<2%).

Update on susceptibility of zoonotic and animal influenza viruses to approved antiviral agents

From May 2023 to May 2024, clade 2.3.4.4b A(H5N1) highly pathogenic avian influenza (HPAI) viruses continued to be detected in various regions of the world. Since early 2024, there has been an outbreak of clade 2.3.4.4b A(H5N1) genotype B3.13 viruses in dairy cattle in several states in the United States of America, resulting in sporadic zoonotic infections in humans. In addition, human infection with clade 2.3.2.1c A(H5N1) HPAI has been reported in Cambodia and Viet Nam. WHO CCs, participating NICs and WHO H5 reference laboratories reported antiviral susceptibility testing of A(H5N1) HPAI, low pathogenic avian influenza (LPAI) of various subtypes and swine influenza viruses. Of the clade 2.3.4.4b A(H5N1) HPAI viruses, the NA-T438I substitution, which confers RI by zanamivir and peramivir, was detected at <2% frequency. NA-H275Y, NA-N295S and NA-N295S+NA-T438N associated with RI or HRI by NAIs were also detected among A(H5N1) viruses. NA-T438I has been detected in A(H5N1) viruses isolated from dairy cattle. PA-I38T, PA-A37T and PA-I38M, associated with reduced susceptibility to baloxavir, were detected in A(H5N1) viruses. Most A(H5N1) HPAI viruses remain susceptible to M2 ion channel blockers. Among LPAI, NA-H274Y with HRI by oseltamivir was detected in one A(H8N4) isolate. PA-E199G with reduced susceptibility to baloxavir was detected in one A(H9N2) virus. Overall, animal or zoonotic influenza viruses with reduced susceptibility to NAIs or baloxavir were detected at very low frequencies.

Update of protocols and guidance for GISRS laboratories

Genotypic and/or phenotypic assays can be used to monitor the susceptibility of influenza viruses to NAIs and baloxavir. The WHO AVWG routinely reviews and updates information on NA{3,4} and PA{5} amino acid substitutions associated with reduced susceptibility to NAIs and baloxavir, respectively. Reference virus panels that can be used for NAI and baloxavir susceptibility testing are available for GISRS laboratories at the International Reagent Resource.{6} The WHO AVWG will develop an algorithm for NICs to decide on testing strategies (genotypic versus phenotypic) and methods according to their capacity. Guidance on phenotypic assays for NAI susceptibility testing is provided in a WHO guidance document to NICs, which was updated in 2018.{7} A new phenotypic assay has been developed for testing susceptibility to baloxavir.{8} The protocol will be posted on the WHO website. The WHO-AVWG will also update the WHO guidance document to NICs to include the new phenotypic assay for baloxavir susceptibility testing. In addition, the WHO AVWG will work with the Global Initiative on Sharing All Influenza Data{9} to facilitate identification of NA and PA substitutions in submitted sequences.

Review of external quality assessment programme (EQAP) panels

EQAP was initiated in 2007, and the antiviral panel was introduced in 2013 (panel 12) as an optional component of EQAP to evaluate the ability of NICs to identify influenza viruses with reduced susceptibility to NAIs. Genotypic testing for baloxavir susceptibility was introduced in 2020 (panel 19) for educational purpose (i.e. not scored). Results for the 2023 Global EQAP panel were reported at the 13th WHO AVWG meeting. A total of 178 laboratories participated in the 2023 EQAP; 46 (25.8%) participated in NAI susceptibility testing and 16 (9.0%) in baloxavir susceptibility testing. The results from the Global EQAP antiviral panel are used by members of the WHO AVWG to assess the training requirements of NICs.

Way forward

Two reports, on global antiviral surveillance in 2020-2023 and in 2023–2024, are being prepared for publication. The next WHO AVWG meeting is scheduled for June 2025.

___

{1} Leung RC et al. Global emergence of neuraminidase inhibitor-resistant influenza A(H1N1)pdm09 viruses with I223V and S247N mutations: implications for antiviral resistance monitoring. Lancet Microbe. 2024;5(7):627–8. doi:10.1016/S26665247(24)00037-5.

{2} Patel MC et al. Multicountry spread of influenza A(H1N1)pdm09 viruses with reduced oseltamivir inhibition, May 2023-February 2024. Emerg Infect Dis. 2024;30(7):1410–5. doi:10.3201/eid3007.240480.

{3} Summary of neuraminidase (NA) amino acid substitutions associated with reduced inhibition by neuraminidase inhibitors (NAIs). Geneva: World Health Organization; 2023 (https://www.who.int/publications/m/item/summary-of-neuraminidase-(na)-amino-acid-substitutions-associated-with-reduced-inhibition-by-neuraminidase-inhibitors-(nais).

{4} Summary of neuraminidase (NA) amino acid substitutions associated with reduced inhibition by neuraminidase inhibitors (NAIs) among avian influenza viruses of Group 1 and Group 2 NAs. Geneva: World Health Organization; 2024 (https://www. who.int/publications/m/item/summary-of-neuraminidase-(na)-amino-acid-substitutions-associated-with-reduced-inhibition-by-neuraminidase-inhibitors-(nais)among-avian-influenza-viruses-of-group-1-and-group-2-nas).

{5} Summary of polymerase acidic (PA) protein amino acid substitutions analysed for their effects on baloxavir susceptibility. Geneva: World Health Organization; 2024 (https://www.who.int/publications/m/item/summary-of-polymerase-acidic-(pa)-protein-amino-acid-substitutions-analysed-for-their-effects-on-baloxavirsusceptibility).

{6} See https://www.internationalreagentresource.org.

{7} Practical guidance for national influenza centres establishing or implementing neuraminidase inhibitor susceptibility surveillance. Geneva: World Health Organization; 2024 (https://www.who.int/publications/i/item/practical-guidance-for-national-inf luenza-centres-establishing-or-implementing-neuraminidase-inhibitor-susceptibility-surveillance).

{8} Baloxavir susceptibility assessment using influenza replication inhibition neuraminidase-based assay (IRINA). Atlanta (GA): Centers for Disease Control and Prevention; 2023 (https://cdn.who.int/media/docs/default-source/influenza/avwg/ cdc-phenotypic-lp-492rev01d—baloxavir-susceptibility-assessment-using-irina. pdf?sfvrsn=f24254ac_3).

{9} See https://gisaid.org.

_____

#aH3n2 #aH5n1 #aH9n2 #amantadine #antivirals #AVIANINFLUENZA #baloxavir #birdFlu #drugsResistance #h1n1pdm09 #h5n1 #health #influenza #oseltamivir #science #SEASONALINFLUENZA #updates #WHO #zanamivir

#ah3n2 #ah5n1 #ah9n2 #amantadine #antivirals #avianinfluenza

ETIDIoH @[email protected] · 2024-11-06 · 20:37 UTC

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.11.04.621830v1

Abstract
Airborne transmission is an essential mode of infection and spread of influenza viruses among humans. However, most studies use liquid inoculum for virus infection. To better replicate natural airborne infections in vitro, we generated a calm-aerosol settling chamber system designed to examine the aerosol infectivity of influenza viruses in different cell types. Aerosol inoculation was characterized for multiple influenza A virus (FLUAV) subtypes, including a pandemic 2009 H1N1, a seasonal swine H3N2, and an avian H9N2 using this exposure system. While each FLUAV strain displayed high infectivity within MDCK cells via liquid inoculation, differences in infectivity were observed during airborne inoculation. This was further observed in recently developed immortalized differentiated human airway epithelial cells (BCi-NS1.1) cultured in an air-liquid interface. The airborne infectious dose 50 for each virus was based on the exposure dose per well. Our findings indicate that this system has the potential to enhance our understanding of the factors influencing influenza transmission via the airborne route. This could be invaluable for conducting risk assessments, potentially reducing the reliance on extensive and costly in vivo animal studies.

____

https://etidioh.wordpress.com/2024/11/06/air-liquid-interface-model-for-influenza-aerosol-exposure-in-vitro/

#aH3n2 #aH9n2 #abstract #avianFlu #birdFlu #h1n1pdm09 #health #influenza #influenzaA #news #pathogensAirborneTransmission #research

#ah3n2 #ah9n2 #abstract #avianflu #birdflu #h1n1pdm09

ETIDIoH @[email protected] · 2024-11-06 · 20:37 UTC

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.11.04.621830v1

Abstract
Airborne transmission is an essential mode of infection and spread of influenza viruses among humans. However, most studies use liquid inoculum for virus infection. To better replicate natural airborne infections in vitro, we generated a calm-aerosol settling chamber system designed to examine the aerosol infectivity of influenza viruses in different cell types. Aerosol inoculation was characterized for multiple influenza A virus (FLUAV) subtypes, including a pandemic 2009 H1N1, a seasonal swine H3N2, and an avian H9N2 using this exposure system. While each FLUAV strain displayed high infectivity within MDCK cells via liquid inoculation, differences in infectivity were observed during airborne inoculation. This was further observed in recently developed immortalized differentiated human airway epithelial cells (BCi-NS1.1) cultured in an air-liquid interface. The airborne infectious dose 50 for each virus was based on the exposure dose per well. Our findings indicate that this system has the potential to enhance our understanding of the factors influencing influenza transmission via the airborne route. This could be invaluable for conducting risk assessments, potentially reducing the reliance on extensive and costly in vivo animal studies.

____

https://etidioh.wordpress.com/2024/11/06/air-liquid-interface-model-for-influenza-aerosol-exposure-in-vitro/

#aH3n2 #aH9n2 #abstract #avianFlu #birdFlu #h1n1pdm09 #health #influenza #influenzaA #news #pathogensAirborneTransmission #research

#ah3n2 #ah9n2 #abstract #avianflu #birdflu #h1n1pdm09

ETIDIoH @[email protected] · 2024-11-06 · 20:37 UTC

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.11.04.621830v1

Abstract
Airborne transmission is an essential mode of infection and spread of influenza viruses among humans. However, most studies use liquid inoculum for virus infection. To better replicate natural airborne infections in vitro, we generated a calm-aerosol settling chamber system designed to examine the aerosol infectivity of influenza viruses in different cell types. Aerosol inoculation was characterized for multiple influenza A virus (FLUAV) subtypes, including a pandemic 2009 H1N1, a seasonal swine H3N2, and an avian H9N2 using this exposure system. While each FLUAV strain displayed high infectivity within MDCK cells via liquid inoculation, differences in infectivity were observed during airborne inoculation. This was further observed in recently developed immortalized differentiated human airway epithelial cells (BCi-NS1.1) cultured in an air-liquid interface. The airborne infectious dose 50 for each virus was based on the exposure dose per well. Our findings indicate that this system has the potential to enhance our understanding of the factors influencing influenza transmission via the airborne route. This could be invaluable for conducting risk assessments, potentially reducing the reliance on extensive and costly in vivo animal studies.

____

https://etidioh.wordpress.com/2024/11/06/air-liquid-interface-model-for-influenza-aerosol-exposure-in-vitro/

#aH3n2 #aH9n2 #abstract #avianFlu #birdFlu #h1n1pdm09 #health #influenza #influenzaA #news #pathogensAirborneTransmission #research

#ah3n2 #ah9n2 #abstract #avianflu #birdflu #h1n1pdm09

ETIDIoH @[email protected] · 2024-11-06 · 20:37 UTC

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.11.04.621830v1

Abstract
Airborne transmission is an essential mode of infection and spread of influenza viruses among humans. However, most studies use liquid inoculum for virus infection. To better replicate natural airborne infections in vitro, we generated a calm-aerosol settling chamber system designed to examine the aerosol infectivity of influenza viruses in different cell types. Aerosol inoculation was characterized for multiple influenza A virus (FLUAV) subtypes, including a pandemic 2009 H1N1, a seasonal swine H3N2, and an avian H9N2 using this exposure system. While each FLUAV strain displayed high infectivity within MDCK cells via liquid inoculation, differences in infectivity were observed during airborne inoculation. This was further observed in recently developed immortalized differentiated human airway epithelial cells (BCi-NS1.1) cultured in an air-liquid interface. The airborne infectious dose 50 for each virus was based on the exposure dose per well. Our findings indicate that this system has the potential to enhance our understanding of the factors influencing influenza transmission via the airborne route. This could be invaluable for conducting risk assessments, potentially reducing the reliance on extensive and costly in vivo animal studies.

____

https://etidioh.wordpress.com/2024/11/06/air-liquid-interface-model-for-influenza-aerosol-exposure-in-vitro/

#aH3n2 #aH9n2 #abstract #avianFlu #birdFlu #h1n1pdm09 #health #influenza #influenzaA #news #pathogensAirborneTransmission #research

#research #pathogensairbornetransmission #news #influenzaa #influenza #health

ETIDIoH @[email protected] · 2024-10-24 · 08:25 UTC

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.10.23.619695v1

Abstract
The most recent outbreak of highly pathogenic avian H5 influenza (HPAI) virus in cattle is now widespread across the U.S. with spillover events happening to other mammals, including humans. Several human cases have been reported with clinical signs ranging from conjunctivitis to respiratory illness. However, most of those infected report mild to moderate symptoms, while previously reported HPAI H5Nx infections in humans have had mortality rates upwards of 50%. We recently reported that mice with pre-existing immunity to A/Puerto Rico/08/1934 H1N1 virus were protected from lethal challenge from highly pathogenic clade 2.3.4.4b H5N1 influenza virus. Here, we demonstrate that mice infected with the 2009 pandemic H1N1 virus strain A/California/04/2009 (Cal09) or vaccinated with a live-attenuated influenza vaccine (LAIV) were moderately-to-highly protected against a lethal A/bovine/Ohio/2024 H5N1 virus challenge. We also observed that ferrets with mixed pre-existing immunity, either from LAIV vaccination and/or from Cal09 infection, showed protection against a HPAI H5N1 clade 2.3.4.4b virus isolated from a cat. Notably, this protection occurred independently of any detectable hemagglutination inhibition titers (HAIs) against the H5N1 virus. To explore factors that may contribute to protection, we conducted detailed T cell epitope mapping using previously published sequences from H1N1 strains. This analysis revealed a high conservation of amino acid sequences within the internal proteins of our bovine HPAI H5N1 virus strain. These data highlight the necessity to explore additional factors that contribute to protection against HPAI H5N1 viruses, such as memory T cell responses, in addition to HA-inhibition or neutralizing antibodies.

____

https://etidioh.wordpress.com/2024/10/24/immune-history-modifies-disease-severity-to-hpai-h5n1-clade-2-3-4-4b-viral-challenge/

#aH1n1 #aH5n1 #abstract #animalModels #avianInfluenza #AVIANINFLUENZA #birdFlu #ferrets #h1n1pdm09 #h5n1 #health #immuneSystem #news #research

#ah1n1 #ah5n1 #abstract #animalmodels #avianinfluenza #birdflu

Giuseppe Michieli @[email protected] · 2024-08-31 · 16:49 UTC

Whole-Genome #Analysis of #Influenza #H1N1pdm09 Viruses Isolated from ILI #Outpatients in #Myanmar & CA #Oseltamivir-Resistant Strains Present from 2015 to 2019 https://pubmed.ncbi.nlm.nih.gov/39205274/?utm_source=Feedly&utm_medium=rss&utm_campaign=None&utm_content=10ykRO9og5pGdo51l9DEPEpOJ3DVFIn__QK2QPM3dci1C1dEYq&fc=None&ff=20240831103754&v=2.18.0.post9+e462414

3 viruses possessed the #H275Y substitution in #neuraminidase protein, appearing to be community-acquired without prior administration of neuraminidase inhibitors. These viruses exhibited highly reduced susceptibility to #oseltamivir and #peramivir.

#analysis #influenza #h1n1pdm09 #outpatients #myanmar #oseltamivir

Giuseppe Michieli @[email protected] · 2024-08-15 · 08:16 UTC

Whole- #Genome #Analysis of #Influenza #H1N1pdm09 Viruses Isolated from #ILI #Outpatients in #Myanmar & Community-Acquired #Oseltamivir - #Resistant Strains Present from 2015 to 2019 https://www.mdpi.com/1999-4915/16/8/1300

1 virus intra-subtype reassortment, collected in the '15 season. 3 viruses possessed #H275Y substitution in NA protein, appearing to be CA without prior administration of neuraminidase #inhibitors. These viruses exhibited highly reduced susceptibility to #oseltamivir & #peramivir.

#genome #analysis #influenza #h1n1pdm09 #ili #outpatients

Giuseppe Michieli @[email protected] · 2024-07-11 · 08:25 UTC

Increase of #Synergistic Secondary #Antiviral #Mutations in the #Evolution of #H1N1pdm09 #Influenza Virus #Neuraminidases, Vaccines: https://www.mdpi.com/1999-4915/16/7/1109

The data indicate a slight increase in viral NA bearing two additional potentially synergistic substitutions, NA-I223V and NA-S247N, in the 2023–2024 season, which both result in a slight reduction in susceptibility to NA inhibitors.

#synergistic #antiviral #mutations #evolution #h1n1pdm09 #influenza

Giuseppe Michieli @[email protected] · 2024-07-09 · 15:41 UTC

Occurrence of Circulating #Antibodies vs #Hemagglutinins of #Influenza Viruses in the 2022/23 Epidemic Season in #Poland, Viruses: https://www.mdpi.com/1999-4915/16/7/1105

Test results have confirmed presence of anti-HA antibodies for #antigens A/Victoria/2570/2019 #H1N1pdm09, A/Darwin/9/2021 #H3N2, B/Austria/1359417/2021 (B/Yamagata lineage) & B/ Phuket/3073/2013 (B/Victoria lineage) present in influenza #vaccine recommended by WHO for 2022/23 epidemic season.

#antibodies #hemagglutinins #influenza #poland #antigens #h1n1pdm09

Giuseppe Michieli @[email protected] · 2024-07-06 · 16:56 UTC

Comprehensive #Molecular #Epidemiology of #Influenza Viruses in #Brazil: Insights from a Nationwide Analysis, BioRxIV, https://www.biorxiv.org/content/10.1101/2024.07.04.602044v1

For #H1N1pdm09, 2022 consensus of 5a.2a.1 & #vaccine strain A/Victoria/2570/2019 had 14 amino acid #substitutions. Key residues such as H180, D187, K219, R223, E224, & T133 are involved in hydrogen interactions with #sialic acids, while N130, K142, and D222 may influence distance interactions based on docking analyses.

#molecular #epidemiology #influenza #brazil #h1n1pdm09 #vaccine

Giuseppe Michieli @[email protected] · 2024-06-20 · 19:35 UTC

#Duration of #fever in #children infected with #influenza #H1N1pdm09, #H3N2 or B virus & treated with #baloxavir, #oseltamivir, #laninamivir, or #zanamivir in #Japan during the 2012–13 & 2019–20 seasons, Antiviral Res.: https://www.sciencedirect.com/science/article/pii/S0166354224001475?via%3Dihub

We compared fever duration between baloxavir- & 3 NAIs-treated groups. ...For influenza A, fever duration in baloxavir- & NAIs-treated groups was similar. For influenza B, fever duration was ∼15 h shorter in baloxavir-treated group.

#duration #fever #children #influenza #h1n1pdm09 #h3n2

Giuseppe Michieli @[email protected] · 2024-06-12 · 16:38 UTC

#Multicountry #Spread of #Influenza #H1N1pdm09 Viruses with Reduced #Oseltamivir #Inhibition, May 2023–February 2024, Emerg Infect Dis.: https://wwwnc.cdc.gov/eid/article/30/7/24-0480_article

Since May 2023, a novel combination of NA #mutations, I223V+S247N, has been detected in viruses collected in countries spanning 5 continents, mostly in #Europe (67/101). Viruses belong to 2 phylogenetically distinct groups & display ≈13-fold reduced inhibition by oseltamivir while retaining normal susceptibility to other antivirals.

#multicountry #spread #influenza #h1n1pdm09 #oseltamivir #inhibition

Giuseppe Michieli @[email protected] · 2024-02-07 · 16:24 UTC

-- According to sequencing results, virus shares 99% similarity with the A/Paraná/ 20675/2022 (A/ #H1N1pdm09-like) virus previously detected in a human case from city of Toledo-Paraná in Oct 2022. #Segments #PB2, #PB1, #PA, NA, and MP corresponded to virus A/Paraná/10835/2021 (A/H1N1pdm09-like) also reported in city of Toledo, & #NP and NS #segments corresponded to virus A/Paraná/44706/2022 (A/ #H3N2v) reported in city of Santa Helena, also in the state of #Paraná

#h1n1pdm09 #segments #pb2 #pb1 #pa #np

Giuseppe Michieli @[email protected] · 2024-01-09 · 20:36 UTC

#Italy, two adult patients died of #Influenza #H1N1pdm09 one after another at #Vicenza #hospital, 3 others hospitalized treated in #ICU with #ECMO, #health officials call people to promptly get vaccinated, https://www.ilfattoquotidiano.it/2024/01/09/influenza-suina-due-morti-in-poche-ore-nellospedale-di-vicenza-altri-tre-ricoverati/7405411/

#italy #influenza #h1n1pdm09 #vicenza #hospital #icu

Giuseppe Michieli @[email protected] · 2023-11-04 · 16:14 UTC

#Russia, According to genetic #analysis conducted in St. Petersburg, 9 A #H1N1pdm09 {#influenza} viruses had the H275Y #substitution in #neuraminidase responsible for resistance to #oseltamivir. NIC: https://www.influenza.spb.ru/en/influenza_surveillance_system_in_russia/epidemic_situation/ #antivirals #NAIs

#russia #analysis #h1n1pdm09 #influenza #substitution #neuraminidase

Giuseppe Michieli @[email protected] · 2023-10-11 · 15:29 UTC

''In 2022, flu #H3N2 viruses predominated over #H1N1pdm09 & B viruses, accounting for 77% of all viruses analysed. Majority of #H1N1pdm09, #H3N2 & flu B viruses analysed at Centre were found to be antigenically and genetically similar to respective #WHO recommended #vaccine #strains for the S hemisphere in 2022. Of 3,372 samples tested for susceptibility to the #NAIs #oseltamivir & #zanamivir, 2 H1N1pdm09 viruses showed highly reduced inhibition against oseltamivir.''

#h3n2 #h1n1pdm09 #who #vaccine #strains #nais