Vaccination and surveillance for high pathogenicity avian influenza in poultry—current situation and perspectives

Biologicals, Journal Year: 2025, Volume and Issue: 91, P. 101840 - 101840

Published: May 13, 2025

The International Alliance for Biological Standardization (IABS), in collaboration with the World Organization Animal Health (WOAH) convened a hybrid meeting on 22-23 October 2024 at WOAH Headquarters (HQ) Paris, France to discuss global state of vaccination and surveillance high pathogenicity avian influenza (HPAI) poultry. primary objective was advance acceptance both control virus spread reduce disease. Vaccination is increasingly recognized as tool complement biosecurity, movement controls stamping-out infected flocks. However, concerns persist regarding risk undetected, sustained transmission (silent infection) vaccinated flocks result inadequate surveillance. This has contributed hesitancy trade barriers. aimed assess current art HPAI programs populations their effectiveness. Representatives multiple stakeholders were invited share experiences perspectives use accompanying growing H5N1 panzootic its impact. Several conclusions recommendations emerged essential advancing strategies. These included (1) utility quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) sensitive, specific economical detect populations, (2) regular testing dead birds within flock highly effective method early detection outbreaks demonstrating freedom from infection and, (3) importance collecting information circulating field strains selection candidate vaccine antigens ensure adequate efficacy. Testing sentinel deemed less serological considered more useful assessing immunity levels than determining status flock. There broad agreement need standardize outcomes terms accepted confidence promote safe fair trade. it acknowledged that context pragmatic considerations will shape development situation plans, which must be statistically valid, scientifically sound, economically feasible operationally sustainable governments industry. Concomitantly, recommended policies tied should based solely science risks. To this end, enforcement existing international rules resolution disputes are shared responsibility. Peer reviewed publications proposed central mechanism developing stronger guidelines needed facilitate agreements enable implementation programs. Rapid dissemination information, consistent messaging exchange isolates also seen critical coordinating an response controlling HPAI.

Language: Английский

The Haemagglutinin Genes of the UK Clade 2.3.4.4b H5N1 Avian Influenza Viruses from 2020 to 2022 Retain Strong Avian Phenotype

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: July 9, 2024

Abstract Since 2020, the United Kingdom (UK) has suffered repeated epizootics of clade 2.3.4.4b H5 high pathogenicity avian influenza viruses (HPAIVs) in wild birds and poultry, resulting substantial economic losses due to enforced statutory control. The rapid evolution HPAIVs continues raise concern with heightened zoonotic pandemic risks. immunodominant haemagglutinin glycoprotein (HA) is crucial for virus receptor binding pH-induced fusion viral cellular membranes. Mutations HA are frequent polymerase error, immune pressure host adaptation, antigenic modulation and/or an expansion tropism, respectively, ultimately hindering control strategies. We evaluated a comprehensive panel representing prevalent genotypes from UK outbreaks spanning 2020 2022 functionality. genes each genotype were assessed through binding, pH fusion, thermostability inhibition assays evaluate factors contributing potential, stability, antigenicity. only bound receptors exhibited at 5.8, above range (pH 5.0 5.5) associated efficient human-to-human transmission. Therefore, these have low immediate threat. Contemporary more thermostable showed drift compared earlier 2017-2018 H5N8 viruses, N236D was identified as significant epitope. findings this study underscore evolving nature highlight importance ongoing surveillance characterisation efforts identify that might contribute risk.

Language: Английский

Validation of a reduction in time for avian influenza virus isolation using specific pathogen‐free embryonated chicken eggs

Veterinary Record, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 19, 2024

Abstract Background The international gold standard for avian influenza virus (AIV) diagnosis is isolation (VI) in specific pathogen‐free embryonated chicken eggs (ECEs). AIV typically involves a 6‐day turnaround, during which premises under suspicion notifiable infection are held restriction regardless of molecular diagnoses, often with significant welfare implications. Methods A reduction time negation by VI was investigated following experimental inoculation from known‐positive original clinical material into ECEs. data derived more than 600 case investigations epizootics high‐pathogenicity (HPAIV) Great Britain since 2016 and low‐pathogenicity (LPAIV) cases 2014 were examined to support test timing using alternative regimens. Results HPAIVs isolated the first passage, LPAIV VI, second passage could be reduced 2 days. Power analysis showed that benefit reducing number days outweighed risk missing positive isolate. Limitations Limited available inoculations. Conclusion This truncated methodology, enables an earlier release restrictions, may substantially ease economic implications restriction. It also reduce bird improve standards without loss performance.

Language: Английский