Highly pathogenic avian influenza A(H5N1) virus infection on multiple fur farms in the South and Central Ostrobothnia regions of Finland, July 2023

Eurosurveillance, Journal Year: 2023, Volume and Issue: 28(31)

Published: Aug. 3, 2023

Since mid-July 2023, an outbreak caused by highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b genotype BB is ongoing among farmed animals in South and Central Ostrobothnia, Finland. Infections foxes, American minks raccoon dogs have been confirmed on 20 farms. Genetic analysis suggests introductions from wild birds scavenging for food farm areas. Investigations point to direct transmission between animals. While no human infections detected, control measures are being implemented limit spread exposure.

Language: Английский

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Avian influenza overview April – June 2023

EFSA Journal, Journal Year: 2023, Volume and Issue: 21(7)

Published: July 1, 2023

Between 29 April and 23 June 2023, highly pathogenic avian influenza (HPAI) A(H5N1) virus (clade 2.3.4.4b) outbreaks were reported in domestic (98) wild (634) birds across 25 countries Europe. A cluster of mulard ducks for foie gras production was concentrated Southwest France, whereas the overall situation poultry Europe worldwide has eased. In birds, black-headed gulls several new seabird species, mostly terns (e.g. sandwich terns), heavily affected, with increased mortality being observed both adults juveniles after hatching. Compared to same period last year, dead seabirds have been increasingly found inland not only along European coastlines. As regards mammals, identified 24 cats one caracal Poland between 10 30 2023. Affected animals showed neurological respiratory signs, sometimes mortality, widely scattered nine voivodeships country. All cases are genetically closely related viruses detected (since October 2022, but now sporadic) (December 2022-January 2023) past. Uncertainties still exist around their possible source infection, no feline-to-feline or feline-to-human transmission so far. Since May 2023 as 4 July two clade 2.3.4.4b detections humans from United Kingdom, A(H9N2) A(H5N6) human infections China. addition, person infected A(H3N8) China died. The risk infection currently circulating H5 remains low general population EU/EEA, moderate occupationally otherwise exposed people mammals (wild domesticated).

Language: Английский

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Outbreak of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus in cats, Poland, June to July 2023

Eurosurveillance, Journal Year: 2023, Volume and Issue: 28(31)

Published: Aug. 3, 2023

Background Over a 3-week period in late June/early July 2023, Poland experienced an outbreak caused by highly pathogenic avian influenza (HPAI) A(H5N1) virus cats. Aim This study aimed to characterise the identified and investigate possible sources of infection. Methods We performed next generation sequencing phylogenetic analysis detected viruses Results sampled 46 cats, 25 tested positive for virus. The belong clade 2.3.4.4b, genotype CH (H5N1 A/Eurasian wigeon/Netherlands/3/2022-like). In Poland, this was responsible several poultry outbreaks between December 2022 January 2023 has been only sporadically since February 2023. Viruses from cats were very similar each other, indicating one common source addition, most closely related dead white stork early June. Influenza possessed two amino acid substitutions PB2 protein (526R 627K) which are molecular markers adaptation mammals. presented those mutations (627K), suggests that had spilled over already partially adapted mammalian species. Conclusion scale HPAI H5N1 infection is worrying. One seems be meat, but date no such meat with certainty. Surveillance should stepped up on poultry, also certain species farmed mammals kept close infected farms.

Language: Английский

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Highly Pathogenic Avian Influenza (HPAI) H5 Clade 2.3.4.4b Virus Infection in Birds and Mammals

Animals, Journal Year: 2024, Volume and Issue: 14(9), P. 1372 - 1372

Published: May 2, 2024

Avian influenza viruses (AIVs) are highly contagious respiratory of birds, leading to significant morbidity and mortality globally causing substantial economic losses the poultry industry agriculture. Since their first isolation in 2013–2014, Asian-origin H5 pathogenic avian (HPAI) clade 2.3.4.4b have undergone unprecedented evolution reassortment internal gene segments. In just a few years, it supplanted other AIV clades, now is widespread wild migratory waterfowl, spreading Asia, Europe, Africa, Americas. Wild natural reservoir LPAIVs generally more resistant disease, also manifested high with HPAIV 2.3.4.4b. This caused overt clinical signs mass variety mammalian species never reported before, such as raptors, seabirds, sealions, foxes, others. Most notably, recent outbreaks dairy cattle were associated emergence critical mutations related adaptation, raising concerns about possibility jumping acquisition sustained human-to-human transmission. The main anatomopathological findings virus infection birds non-human mammals hereby summarized.

Language: Английский

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High pathogenic avian influenza A(H5) viruses of clade 2.3.4.4b in Europe—Why trends of virus evolution are more difficult to predict

Virus Evolution, Journal Year: 2024, Volume and Issue: 10(1)

Published: Jan. 1, 2024

Since 2016, A(H5Nx) high pathogenic avian influenza (HPAI) virus of clade 2.3.4.4b has become one the most serious global threats not only to wild and domestic birds, but also public health. In recent years, important changes in ecology, epidemiology, evolution this have been reported, with an unprecedented diffusion variety affected birds mammalian species. After two consecutive devastating epidemic waves Europe 2020-2021 2021-2022, second recognized as largest epidemics recorded so far, begun circulate endemically European bird populations. This study used complete genomes 1,956 HPAI viruses investigate during varying epidemiological outline. We investigated spatiotemporal patterns to/from within 2021-2022 waves, providing evidence ongoing transmission dynamics disease epidemiology. demonstrated genetic diversity circulating viruses, which undergone frequent reassortment events, for first time a overview proposed nomenclature multiple genotypes 2020-2022. described emergence new genotype gull adapted genes, offered opportunity occupy ecological niches, driving endemicity population. The propensity reassortment, its jumps progressively wider number host species, including mammals, rapid acquisition adaptive mutations make trend spread difficult predict unfailing evolving scenario.

Language: Английский

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An Update on Highly Pathogenic Avian Influenza A(H5N1) Virus, Clade 2.3.4.4b

The Journal of Infectious Diseases, Journal Year: 2024, Volume and Issue: 230(3), P. 533 - 542

Published: Sept. 15, 2024

Abstract Since the resurgence of highly pathogenic avian influenza (HPAI) A(H5N1) virus, clade 2.3.4.4b, during 2021, these viruses have spread widely among birds worldwide, causing poultry outbreaks and infections a wide range terrestrial marine mammal species. During 2024, HPAI was detected in dairy cattle for first time caused an ongoing multistate outbreak, with high levels virus documented raw cow milk. Human 2.3.4.4b from exposures to infected or resulted spectrum illness severity, conjunctivitis mild respiratory severe fatal pneumonia different countries. Vigilance, stronger global virologic surveillance birds, poultry, mammals, humans, characterization rapid data sharing, is needed inform threat viruses, as they continue evolve, public health.

Language: Английский

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Drivers for a pandemic due to avian influenza and options for One Health mitigation measures

EFSA Journal, Journal Year: 2024, Volume and Issue: 22(4)

Published: April 1, 2024

Abstract Avian influenza viruses (AIV) remain prevalent among wild bird populations in the European Union and Economic Area (EU/EEA), leading to significant illness death of birds. Transmission between mammal species has been observed, particularly fur animal farms, where outbreaks have reported. While transmission from infected birds humans is rare, there instances exposure these since 2020 without any symptomatic infections reported EU/EEA. However, continue evolve globally, with migration birds, new strains carrying potential mutations for mammalian adaptation could be selected. If avian A(H5N1) acquire ability spread efficiently humans, large-scale occur due lack immune defences against H5 humans. The emergence AIV capable infecting mammals, including can facilitated by various drivers. Some intrinsic drivers are related virus characteristics or host susceptibility. Other extrinsic may increase mammals thereby stimulating mutation mammals. Extrinsic include ecology species, such as wildlife, human activities like farming practices use natural resources, climatic environmental factors. One Health measures mitigate risk adapting focus on limiting preventing spread. Key options actions enhancing surveillance targeting animals, ensuring access rapid diagnostics, promoting collaboration sectors, considering implementation preventive vaccination poultry. Effective communication different involved target audiences should emphasised, well strengthening veterinary infrastructure, enforcing biosecurity at reducing wildlife contact domestic animals. Careful planning poultry farming, especially areas high waterfowl density, highlighted effective reduction.

Language: Английский

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Avian influenza overview March–June 2024

EFSA Journal, Journal Year: 2024, Volume and Issue: 22(7)

Published: July 1, 2024

Abstract Between 16 March and 14 June 2024, 42 highly pathogenic avian influenza (HPAI) A(H5) virus detections were reported in domestic (15) wild (27) birds across 13 countries Europe. Although the overall number of Europe has not been this low since 2019–2020 epidemiological year, HPAI viruses continue to circulate at a very level. Most poultry due indirect contact with birds, but there was also secondary spread. Outside Europe, situation intensified particularly USA, where new A(H5N1) genotype (B3.13) identified >130 dairy herds 12 states. Infection cattle appears be centred on udder, milk from infected animals showing high viral loads representing vehicle transmission. Apart cattle, two other mammal species (alpaca walrus) for first time. 20 human cases infection Vietnam (one A(H5N1), one A(H9N2)), Australia (with travel history India, A(H5N1)), USA (three China (two A(H5N6), three A(H9N2), A(H10N3)), India Mexico fatal A(H5N2) case). The latter case laboratory‐confirmed subtype A(H5N2). had exposure poultry, live markets, or prior detection onset illness. Human infections remain rare no human‐to‐human transmission observed. risk currently circulating clade 2.3.4.4b remains general public EU/EEA. low‐to‐moderate those occupationally otherwise exposed contaminated environments.

Language: Английский

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Preparedness, prevention and control related to zoonotic avian influenza

EFSA Journal, Journal Year: 2025, Volume and Issue: 23(1)

Published: Jan. 1, 2025

A risk assessment framework was developed to evaluate the zoonotic potential of avian influenza (AI), focusing on virus mutations linked phenotypic traits related mammalian adaptation identified in literature. Virus sequences were screened for presence these and their geographical, temporal subtype-specific trends. Spillover events mammals (including humans) human seroprevalence studies also reviewed. Thirty-four associated with five (increased receptor specificity, haemagglutinin stability, neuraminidase enhanced polymerase activity evasion innate immunity) shortlisted. AI viruses (AIVs) carrying multiple adaptive belonged both low highly pathogenic subtypes, mainly A(H9N2), A(H7N9), A(H5N6) A(H3N8), sporadic primarily detected Asia. In EU/EEA, H5Nx clade 2.3.4.4b, which have increased opportunities evolution due widespread circulation birds occasional cases/outbreaks mammals, acquired highest number traits. Adaptive traits, such as immune evasion, frequently acquired, while receptor-specific remained rare. Globally, cases remain rare, majority overall A(H5N1), A(H5N6), A(H7N9) A(H9N2) that are among subtypes tend a higher The main drivers include host characteristics, external factors increasing AIV exposure humans wild domestic (e.g. activities ecological factors). Comprehensive surveillance AIVs targeting whole genome sequencing animals is essential early detection efficient implementation control measures. All preparedness, preventive measures must be implemented under One Health tailored setting epidemiological situation; particular, monitoring, biosecurity, genomic global collaboration critical mitigating risks AIV.

Language: Английский

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The Haemagglutinin Gene of Bovine-Origin H5N1 Influenza Viruses Currently Retains Receptor-binding and pH-fusion Characteristics of Avian Host Phenotype

Emerging Microbes & Infections, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

Clade 2.3.4.4b H5N1 high pathogenicity avian influenza virus (HPAIV) has caused a panzootic affecting all continents except Australia, expanding its host range to several mammalian species. In March 2024, HPAIV was first detected in dairy cattle and goats the United States. Over 891 farms across 16 states have tested positive until 25th December with zoonotic infections reported among workers. This raises concerns about undergoing evolutionary changes that could enhance potential. The Influenza glycoprotein haemagglutinin (HA) facilitates entry into cells through receptor binding pH-induced fusion cellular membranes. Adaptive HA modulate virus-host cell interactions. study compared genes of goat viruses dominant avian-origin clade Kingdom, focusing on binding, pH fusion, thermostability. All showed exclusively avian-like receptors, 5.9, outside associated efficient human airborne transmissibility (pH 5.0 5.5). We further investigated impact emerging substitutions seen ongoing outbreaks, but saw little phenotypic difference, continued exclusive analogues pHs above 5.8. suggests from outbreaks do not pose an enhanced threat circulating viruses. However, given rapid evolution H5 viruses, continuous monitoring updated risk assessments remain essential understanding pandemic risks.

Language: Английский

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