How close is the next {#influenza} #pandemic? Chinese #researchers {George F. Gao} have some answers https://www.scmp.com/news/china/science/article/3289473/how-close-next-pandemic-chinese-researchers-have-some-answers?utm_source=feedly_feed
China’s top infectious disease expert says a strain {#H2N2} of avian #influenza virus is adapting and could make the leap from #birds to #mammals.
Dual #receptor-binding, #infectivity, and #transmissibility of an emerging #H2N2 low pathogenicity avian #influenza virus
Source: Nature Communications, AbstractThe 1957 H2N2 influenza pandemic virus has disappeared from humans since 1968, while H2N2 avian influenza viruses (AIVs) are still circulating in birds. It is necessary to reveal the recurrence risk and potential cross-species infection of these AIVs from avian to mammals. We find that H2 AIVs circulating in…
Source: Nature Communications, AbstractThe 1957 H2N2 influenza pandemic virus [A(H2N2)pdm1957] has disappeared from humans since 1968, while H2N2 avian influenza viruses (AIVs) are still circulatin…
Novel #reassortant #H2N2 low pathogenic avian #influenza virus in live #bird #markets in the Northeastern #USA, 2019-2023
Source: Avian Pathology, ABSTRACTThe H2N2 avian influenza viruses (AIV) have been reported in the Northeast United States of America (USA) live bird market (LBM) system since 2014. In this study, we investigated the genetic evolution and characterized molecular markers of the recent H2N2 AIVs in LBMs in the Northeast USA. Phylogenetic analyses…
Source: Avian Pathology, ABSTRACTThe H2N2 avian influenza viruses (AIV) have been reported in the Northeast United States of America (USA) live bird market (LBM) system since 2014. In this study, w…
A(#H2N2) and A(#H3N2) #influenza #pandemics elicited durable cross-reactive and protective #antibodies against avian #N2 #neuraminidases, Nat Commun.: https://www.nature.com/articles/s41467-024-49884-9
The anti-AIV N2 antibodies titers correlate with antibody titers to the 1957 N2, suggesting that #exposure to the A(H2N2) virus contribute to this reactivity. These findings underscore the critical role of neuraminidase #immunity in #zoonotic and pandemic influenza #risk #assessment.
Using more than 300 serum samples from individuals with an age range of 1-88 years old, the authors here show that older adults possess higher breadth of antibody reactivity to avian influenza virus (AIV) neuraminidases, potentially explaining the age-specific risks of AIV human infections.
The #H4 #subtype of avian #influenza virus: a #review of its historical #evolution, global #distribution, adaptive #mutations and #receptor #binding properties, Poul Sci.: https://www.sciencedirect.com/science/article/pii/S0032579124004929?via%3Dihub
The Q226L/G228S #substitutions in the receptor-binding site have led to structural changes in globular head of H4 AIV, resulting in a configuration similar to that of #pandemic #H2N2 and #H3N2 human influenza viruses.
Immune #memory shapes #human polyclonal #antibody responses to #H2N2 #vaccination https://pubmed.ncbi.nlm.nih.gov/38717904/?utm_source=Feedly&utm_medium=rss&utm_campaign=None&utm_content=1fgJURi2yzLesFml6et0Bb6krzs_FrNIYgPYVFN50JPwVNFg9s&fc=None&ff=20240508195305&v=2.18.0.post9+e462414
Our findings accentuate the impact of pre-existing influenza exposure on serum antibody responses post-vaccination.
Influenza A virus subtype H2N2, which caused the 1957 influenza pandemic, remains a global threat. A recent phase 1 clinical trial investigating a ferritin nanoparticle vaccine displaying H2 hemagglutinin (HA) in H2-naive and H2-exposed adults enabled us to perform comprehensive structural and bioch …
Influenza A viruses of the H2N2 subtype sparked a pandemic in 1957 and circulated in humans until 1968. Because A/H2N2 viruses still circulate in wild birds worldwide and human population immunity is low, the transmissibility of six avian A/H2N2 viruses was investigated in the ferret model. None of the avian A/H2N2 viruses was transmitted between ferrets, suggesting that their pandemic risk may be low. The transmissibility, receptor binding preference and haemagglutinin (HA) stability of human A/H2N2 viruses were also investigated. Human A/H2N2 viruses from 1957 and 1958 bound to human-type α2,6-linked sialic acid receptors, but the 1958 virus had a more stable HA, indicating adaptation to replication and spread in the new host. This increased stability was caused by a previously unknown stability substitution G205S in the 1958 H2N2 HA, which became fixed in A/H2N2 viruses after 1958. Although individual substitutions were identified that affected the HA receptor binding and stability properties, they were not found to have a substantial effect on transmissibility of A/H2N2 viruses via the air in the ferret model. Our data demonstrate that A/H2N2 viruses continued to adapt during the first year of pandemic circulation in humans, similar to what was previously shown for the A/H1N1pdm09 virus.
Giuseppe Michieli