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Showing posts from March 4, 2026

#Panzootic #H5 #influenza viruses acquired #resistance to human head interface #antibodies

  Abstract Antibodies to the influenza hemagglutinin protein (HA) confer the strongest protection against infection . Immunity elicited by endemic, seasonal, human viruses is correlated with diminished disease severity and death caused by antigenically novel viruses. Antibodies to the HA head interface are broadly protective and abundant in human serologic and memory repertoires . Notably, few head interface antibodies from H5 naive donors are reported to bind H5 HAs . We find head interface antibodies engage a wide range of H5 isolates but fail to engage most isolates from the goose Guangdong (GsGd) lineage . We identify a single substitution, P221S, largely dictates antibody binding. Phylogenetic analysis indicates that P221S arose in a Chinese avian reservoir by the year 2000 . Descendants of these viruses have caused the current global panzootic and have achieved sustained mammal-mammal transmission in farmed and wild mammals. Our findings demonstrate that viral evolution in no...

#Statement of the 44th #Meeting of the #Polio #IHR #Emergency Committee (#WHO, summary)

  {4 March 2026, excerpts} The 44th meeting of the Emergency Committee under the International Health Regulations (IHR or Regulations) on the international spread of poliovirus was convened by the WHO Director-General on 14 January 2026 with eight out of nine Committee members and the adviser meeting via video conference with affected countries, supported by the WHO Secretariat.  The Emergency Committee reviewed the latest epidemiological data on wild poliovirus type 1 (WPV1) and circulating vaccine-derived polioviruses (cVDPV) in the context of the global targets to interrupt endemic WPV1 transmission in 2026 and to stop cVDPV2 outbreaks by 2028 with subsequent certification of WPV1 eradication and cVDPV2 elimination.  Technical updates were received about the situation in the following countries :  - Afghanistan,  - Angola,  - Germany,  - Lao People’s Democratic Republic,  - Namibia,  - Pakistan and  - Papua New Guinea . Amendments to ...

Mechanism of co-transcriptional cap snatching by #influenza #polymerase

  Abstract Influenza virus mRNAs are stable and competent for nuclear export and translation because they receive a 5′ cap(1) structure in a process called cap snatching 1. During cap snatching, the viral RNA-dependent RNA polymerase (FluPol) binds to host RNA polymerase II (Pol II) and the emerging transcript2,3. The FluPol endonuclease then cleaves a capped RNA fragment that subsequently acts as a primer for the transcription of viral genes 4,5. Here we present the cryogenic electron microscopy structure of FluPol bound to a transcribing Pol II in complex with the elongation factor DSIF in the pre-cleavage state. The structure shows that FluPol directly interacts with both Pol II and DSIF , positioning the FluPol endonuclease domain near the RNA exit channel of Pol II . These interactions are important for the endonuclease activity of FluPol and FluPol activity in cells. A second structure , trapped after cap snatching, shows that the cleaved capped RNA rearranges within FluPol, ...

#India - High pathogenicity avian #influenza #H5N1 viruses (Inf. with) (#poultry) - Immediate notification

  A poultry farm in Bihar State. Source:  Link:  https://wahis.woah.org/#/in-review/7319 ____