Biology subjects

Banyard, A. C.

Publications and source records attributed to Banyard, A. C..

At least 19 recordsLinked to original sources

bioRxiv2026

The mammalian-adaptive PB2-E627K substitution preserves viral fitness of clade 2.3.4.4b H5N1 HPAIV in birds.

Since emerging in 2020, clade 2.3.4.4b H5N1 high pathogenicity avian influenza virus (HPAIV) has disseminated globally, causing substantial infection and mortality in wild birds and poultry. Additionally, numerous spill-over events into mammals have occurred, including mass mortalities and sporadic human infections. Such events can drive the acquisition of mammalian-adaptive mutations, which further increase the risk to humans; the most well characterised mutation is the glutamate to lysine change at amino acid position 627 in the polymerase basic 2 protein (PB2-627K). Across avian influenza viruses, PB2-627K enhances polymerase activity and replication in mammalian cells, increasing zoonotic and pandemic potential. However, bioinformatic analyses indicate that PB2-627K remains rare among clade 2.3.4.4b H5N1 viruses circulating in avian populations. Here, we investigated the impact of PB2-627K on viral fitness in avian hosts to assess the potential for mammalian-adapted viruses to re-establish in birds, mimicking infection of avian species following scavenging on mammalian species where PB2-627K has already emerged. Using a representative H5N1 virus (European genotype AB), PB2-627K increased polymerase activity and replication in human cells without compromising replication in avian cells. A mammalian-derived PB2-627K H5N1 isolate from a fox exhibited comparable replication kinetics and transmission efficiency in chickens and ducks to a closely related PB2-627E virus. Notably, PB2-627K remained genetically stable at consensus level following infection and transmission in both avian hosts. These findings demonstrate that mammalian-adaptive mutations acquired during spill-over can be maintained in avian populations, potentially elevating zoonotic risk and underscoring the importance of surveillance for such mutations in birds.

microbiology↗

bioRxiv2026

Revolutionising notifiable avian disease diagnostics: validation of direct swab testing for Avian Influenza and Newcastle disease using the CENOS platform

Existing molecular diagnostic approaches for notifiable avian diseases (NADs) involve a suite of PCR assays that enable both generic detection, and where positive, subtyping of both avian influenza virus (AIV) and Newcastle disease virus (NDV). Novel rapid and direct diagnostic assays for the detection of AIV and NDV were developed and evaluated using unprocessed cloacal (C) and oropharyngeal (OP) poultry swab material. Both assays employ a closed tube direct real-time reverse transcription polymerase chain reaction (RRT-PCR) approach in which viral lysis is achieved by heat treatment and a dedicated PCR compatible buffer, followed by detection using a RRT-PCR approach. Primer and probe sets were designed using globally circulating AIV and NDV sequences collected over the preceding five years, rather than region-specific sequence datasets, so that the assays detect all circulating genotypes. Analytical performance assessment demonstrated that both assays were highly sensitive and specific, successfully detecting all unextracted target antigens without cross reactivity to a panel of other common poultry pathogens. For each assay, viral lysis and amplification were achieved directly from samples at single digit genome copy numbers. Furthermore, low levels of viral RNA could be reliably detected in the presence of C and OP matrix material, providing proof-of-concept for direct detection of these economically significant avian pathogens in a field setting. Additional use case scenarios, including pooled sample screening and combined C/OP testing from individual birds, were also explored. These findings establish a foundation for ongoing studies incorporating paired-sample testing against validated laboratory reference assays.

molecular biology↗

bioRxiv2025

Investigating high pathogenicity avian influenza virus incursions to remote islands: Detection of H5N1 on Gough Island in the South Atlantic Ocean

Understanding the mechanisms underlying the emergence and spread of high pathogenicity avian influenza virus (HPAIV) is critical for tracking its global dissemination, particularly via migratory seabirds, given their role in transmission over long distances. Scavenging seabirds, such as skuas, may act as both reservoirs and vectors, and have been linked to multiple outbreaks since 2021. Here, we report the detection of HPAIV H5N1 clade 2.3.4.4b in three Tristan skua (Stercorarius antarcticus hamiltoni) carcasses on Gough Island in the central South Atlantic Ocean. To investigate potential incursion routes, we combined genomic analyses with year-round tracking data from global location sensors. Although migratory movement patterns suggested southern Africa as the most obvious pathway, the strain detected on Gough Island was more closely related to that identified in South Georgia, indicating that infection may have occurred during the pre-laying exodus, when skuas disperse into frontal waters south of the island. No further cases have been confirmed for Gough, but more systematic monitoring is needed to understand the dynamics of virus infection. The detection of HPAIV H5N1 in skuas on Gough Island highlights the importance of continued vigilance, proactive and geographically inclusive surveillance strategies, and biosecurity measures globally, alongside efforts to reduce other pressures on globally important seabird populations to help strengthen their resilience.

pathology↗

bioRxiv2025

Infection of ratites with clade 2.3.4.4b HPAIV H5N1: Potential implications for zoonotic risk

We detected H5N1 high pathogenicity avian influenza in captive Greater Rhea (Rhea americana). Viral genetic analysis revealed the mammalian associated PB2-E627K mutation, indicating selection of mammalian-relevant mutations in ratites. Pathologic investigation of available tissues demonstrated severe multifocal necrotising inflammation, and a strong vasculotropism.

pathology↗

bioRxiv2025

Genetic reassortment and diversification of host specificity have driven evolutionary trajectories of lineages of panzootic H5N1 influenza

Since 2021, subclade 2.3.4.4b A(H5N1) high pathogenicity avian influenza (HPAI) viruses have undergone changes in ecology and epidemiology, causing a panzootic of unprecedented scale in wild and domestic birds with spill-over infections and perceptible transmission in a range of mammalian species, raising concern over zoonotic potential. HPAI viruses readily exchange gene segments with low pathogenicity avian influenza viruses via reassortment, a mechanism that facilitates pronounced phenotypic change. Observations suggest changes in the seasonality and host range of panzootic viruses, however, data on the role of reassortment in determining such features are limited. Using phylodynamic approaches, we describe the emergence of the panzootic lineage and using a novel global genotype classification system we describe the subsequent emergence and global structuring of genotypes generated by reassortment. Focusing on evolutionary dynamics in Europe, we show reassortment has produced high fitness genotypes with enhanced capacity for transmission and further we show such advantages can be host-dependent, contrasting successful generalist genotypes with a specialist lineage (EA-2022-BB) adapted to birds of the order Charadriiformes. Experimental investigation of NS1-mediated shutoff indicates this Charadriiformes-specialist does not inhibit host cellular gene expression and hamper the defences of more typical hosts such as water- and land-fowl. We attribute this primarily to variation at position 127 of the NS1 protein. Our results emphasise that reassortment has driven phenotypic change, affected viral fitness, and caused diversification of host specificity and seasonality. Such factors should be considered in studies that seek to identify drivers of HPAI spread and map spillover risk. Additionally, relaxation of host specialisation, ecological diversification, and potential endemicity in atypical host populations present new reassortment opportunities that could result in further novel phenotypes.

microbiology↗

bioRxiv2025

Co-circulation of distinct high pathogenicity avian influenza virus (HPAIV) subtypes in a mass mortality event in wild seabirds and co-location with dead seals

H5Nx clade 2.3.4.4b high pathogenicity avian influenza viruses (HPAIV) have been detected repeatedly in Great Britain (GB) since autumn 2020, with H5N1 dominating detections but with low level detection of H5N5 during 2025. Globally, these viruses have caused mass mortalities in captive and wild avian and mammalian populations, including terrestrial and marine mammals. H5N1 has been the dominant subtype, and whilst incursions have overlapped temporally, occurrences have often been spatially distinct. Here, we report the detection of a mortality event in wild birds on the Norfolk coastline in the east of England, where H5N1 HPAIV was detected in five Great Black-backed Gulls (Larus marinus) and a Northern Fulmar (Fulmarus glacialis). Interestingly, at the same site, and as part of the same mortality event, a total of 17 Great Black-backed Gulls, one Herring Gull (Larus argentatus), one Atlantic Puffin (Fratercula arctica) and one Northern Fulmar tested positive for H5N5 HPAIV. Additionally, H5N5 was also detected in 17 co-located Grey Seal carcases (Halichoerus grypus). The H5N1 HPAIV from an infected bird belonged to genotype DI.2, closely related to contemporaneous detections in GB wild birds and poultry. In contrast, all H5N5 HPAIVs from birds and seals were genotype I with a 22-amino acid stalk deletion in NA and the 627K polymorphism in PB2. This represents the first recorded instance in GB of two subtypes being detected within the same avian population at the same location. It is also the first mass detection of HPAIV H5N5 in mammals within GB. Potential infection mechanisms are discussed.

genetics↗

bioRxiv2025

Detection of clade 2.3.4.4b H5N1 high pathogenicity avian influenza virus in a sheep in Great Britain, 2025

Clade 2.3.4.4b H5N1 high pathogenicity avian influenza virus (HPAIV) continues to pose a significant global threat, affecting wild and domestic avian populations, and mammalian species. In early 2024, H5N1 HPAIV was detected in dairy cattle in the United States of America, where it has continued to circulate, with sporadic detections also reported in other ruminant species. The detection of high viral loads in milk from infected cattle, has resulted in several human infections, underscoring the zoonotic potential of these viruses. In response, several countries have intensified surveillance in non-avian species to evaluate the potential for undetected viral circulation in captive mammals. In Great Britain, bulk milk tank testing of cattle and targeted surveillance of captive mammalian species on an infected premises is undertaken in accordance with the outcome of a rapid risk assessment undertaken to determine the epidemiological links between the poultry and captive mammals. A result of this testing was the first recorded detection of clade 2.3.4.4b H5N1 HPAIV in a sheep in March 2025, identified on an infected poultry premises in Great Britain. An initial seropositive result in a single ewe triggered further investigation, confirming serological positivity across repeated sampling and the presence of viral RNA in milk samples. This detection was confined to a single animal and was likely attributable to proximity to infected poultry and a presumed heavily contaminated environment. The implications of this ruminant detection are discussed in the context of interspecies transmission and surveillance strategies.

microbiology↗

bioRxiv2025

Phylogenetic analysis of pigeon paramyxovirus type 1 (PPMV-1) detected in the British Isles between 1983 - 2023.

Newcastle Disease (ND), caused by virulent strains of avian paramyxovirus type-1 (APMV-1), is one of the most important poultry diseases globally due to its economic impact and endemicity in lower- and middle-income countries. A variant of APMV-1 is endemic in Columbiformes (pigeons and doves) worldwide and is commonly termed pigeon paramyxovirus-1 (PPMV-1). Since its initial detection in the 1980s, PPMV-1 has caused numerous ND outbreaks in poultry, including in high income countries, and was the causative agent for the last ND outbreak in the British Isles in 2006. Here, we have undertaken sequencing of PPMV-1 isolates between 1983 and 2023 and define three distinct genotypes of PPMV-1 being present in the British Isles. Analysis of the contemporary VI.2.1.1.2.2 genotype, demonstrated likely incursion from mainland Europe, whilst this genotype has subsequently spread across China, with detection also occurring in Australia. The presence of a virulent fusion-gene cleavage site in sequences highlights the continued risk to poultry from PPMV-1 genotypes which were detected in pigeons and doves across the British Isles.

evolutionary biology↗

bioRxiv2025

Pigeons exhibit low susceptibility and poor transmission capacity for H5N1 clade 2.3.4.4b high pathogenicity avian influenza virus

The ongoing panzootic of H5N1 high pathogenicity avian influenza virus (HPAIV) has caused the deaths of over half a billion wild birds and poultry, and has led to spillover events in both wild and domestic mammals, alongside sporadic human infections. A key driver of this panzootic is the apparent high viral fitness across diverse avian species, which facilitates an increased interface between wild and domestic species. Columbiformes (pigeons and doves) are commonly found on poultry premises, yet little is known about their potential role in contemporary HPAIV disease ecology. Here we investigated the epidemiological role of pigeons (Columba livia) by determining their susceptibility using decreasing doses of clade 2.3.4.4b H5N1 HPAIV (genotype AB). We investigated infection outcomes and transmission potential between pigeons and to chickens. Following direct inoculation, pigeons did not develop clinical signs, and only those inoculated with the highest dose shed viral RNA or seroconverted to H5N1-AB, revealing a MID50 of 105 EID50. Even in the high-dose group, only low-level shedding and environmental contamination was observed, and low-level viral RNA were present in the tissues of directly inoculated pigeons, with no distinct pathological lesions. Pigeons did not transmit the virus to pigeons or chickens placed in direct contact. We observed distinct differences in sialic acid receptor distribution in the pigeon respiratory tract compared to chickens and ducks. Together, these findings suggest that pigeons have low susceptibility to clade 2.3.4.4b H5N1 HPAIV and are unlikely to contribute significantly to virus maintenance, transmission to poultry, or zoonotic infection.

microbiology↗

bioRxiv2025

Diverse Genomic Landscape of Swine Influenza A Virus in England (2014 - 2021)

Surveillance of influenza A viruses in pigs (SwIAV) is critical for identification of novel genetic groups that pose a risk to pig health and might have zoonotic potential. SwIAVs circulating in pigs in England between 2014 and 2021 were characterised using whole genome sequencing (WGS). Haemagglutinin (HA) and neuraminidase (NA) sequencing data from 82 of 368 influenza A positive samples (71 submissions) were determined, identifying H1N1 and H1N2 subtypes from the 1A classical swine and 1B human-seasonal lineages respectively. The 1B lineage viruses were predominant, accounting for 68.29% of sequenced viruses, with 1A lineage viruses comprising 31.71%, primarily from the 1A.3.3.2 clade (2009 H1N1 pandemic origin). This study characterised previously undefined diversity within the 1B lineage which led to the designation of new HA clades 1B.1.1.1, 1B.1.1.2 and 1B.1.1.3. Complete genome data were obtained from 64/82 viruses thereby updating the definition of genetic diversity thresholds and leading to the identification of 24 unique genotypes. All these 64 viruses contained PB2, PB1, PA, NP, MP, and NS gene segments of 2009 H1N1 pandemic origin. These data highlight the increasing divergence of SwIAV within pig populations England and emphasise the requirement for continued genomic surveillance to improve animal health and monitor zoonotic risk.

genomics↗

bioRxiv2025

Investigating Factors Driving Shifts in Subtype Dominance within H5Nx Clade 2.3.4.4b High-Pathogenicity Avian Influenza viruses

H5Nx clade 2.3.4.4b high-pathogenicity avian influenza viruses (HPAIVs) have decimated wild bird and poultry populations globally since the autumn of 2020. In the United Kingdom (UK) and in continental Europe, the H5N8 subtype predominated during the first epizootic wave of 2020/21, with few detections of H5N1. However, during the second (2021/22) and third (2022/23) epizootic waves, H5N1 was the dominant subtype. The rapid shift in dominance from H5N8 to H5N1 was likely driven by a combination of virological, immunological, and/or host-related factors. In this study, we compared viral fitness and immunological responses in ducks, a key reservoir species, using dominant genotypes of H5N1 (genotype AB) and H5N8 (genotype A) from the second wave. While viral shedding dynamics were similar for both viruses, H5N8 was more pathogenic. Antigenic analysis of post-infection duck sera revealed that the haemagglutinin (HA) protein was antigenically similar across clade 2.3.4.4b H5 HPAIVs, but neuraminidase (NA) proteins displayed different patterns of cross-reactivity. We also modelled a scenario where ducks were pre-exposed to H5N1 (genotype C) or H5N8 (genotype A) from the first wave and subsequently challenged with either homologous or heterologous subtypes from the second wave (genotype AB or A). Despite the absence of seroconversion, pre-exposure to different subtypes resulted in varying clinical outcomes following challenge. These findings indicate that both viral and immunological factors likely played significant roles in the emergence and spread of H5Nx HPAIVs in wild bird populations.

microbiology↗

bioRxiv2024

Asymptomatic infection and antibody prevalence to co-occurring avian influenza viruses vary substantially between sympatric seabird species following H5N1 outbreaks

Emerging infectious diseases are of major concern to animal and human health. Recent emergence of high pathogenicity avian influenza virus (HPAIV) (H5N1 clade 2.3.4.4b) led to substantial global mortality across a range of host species. Co-occurring species showed marked differences in mortality, generating an urgent need for better epidemiological understanding within affected populations. We therefore tested for antibodies, indicative of previous exposure and recovery, and for active viral infection in apparently healthy individuals (n=350) across five co-occurring seabird species on the Isle of May, Scotland, during 2023, following H5N1 HPAIV associated mortality in the preceding summer. Antibody prevalence to AIV subtypes varied substantially between species, ranging from 1.1% in European shags (Gulosus aristotelis) (to H5) to 78.7% in black-legged kittiwakes (Rissa tridactyla) (to H16 or both H13 and H16), and between 31-41% for three auk species (H5, H16 or both). At least 20.4% of auks had antibodies to an as yet unidentified subtype, suggesting further subtypes circulating in the population. We found low levels of active, but asymptomatic, AIV infection in individuals (1.6-4.5%), but excluded this as H5N1. Our results emphasise the importance of testing healthy individuals to understand the prevalence of co-circulating AIV subtypes in wild populations, and the potential for future reassortment events which could alter virus behaviour and impact.

ecology↗

bioRxiv2024

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

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

microbiology↗

bioRxiv2024

Validation of Optimized Methods for Avian Influenza Virus Isolation in Specific Pathogen-Free Embryonated Fowl Eggs

The internationally recognised method for diagnosis of avian influenza (AI) is virus isolation (VI) in specific pathogen-free embryonated fowls eggs (EFEs). In Great Britain (GB), AI virus isolation currently involves two passages in EFEs; the first typically of two days duration followed by a second lasting up to four days meaning that premises may remain under restriction for up to six days. Shorter time lengths for AIV isolation were investigated to reduce the time that businesses remain under official restrictions to safely negate AI infection, whilst maintaining test sensitivity. Both experimental inoculations of EFEs and analyses of VI attempts from high pathogenicity (HP) AI disease incursions in GB since 2016 demonstrated that HP viruses were isolated during first passage while for low pathogenicity AI outbreaks, the second passage could be reduced to two days. Power analysis showed that the benefit of reducing the number of days outweighed the risk of missing a positive isolate. This approach will substantially reduce costs to government and industry by releasing restrictions at least two days earlier where samples are negative for viral nucleic acid. Critically, it will reduce welfare implications of housing birds under restriction and improve international standards without loss of test performance.

microbiology↗

bioRxiv2024

Evaluating the epizootic and zoonotic threat of an H7N9 low pathogenicity avian influenza virus (LPAIV) variant associated with enhanced pathogenicity in turkeys

Between 2013-2017, A/Anhui/1/13-lineage (H7N9) low pathogenicity avian influenza virus (LPAIV) was epizootic in chickens in China causing mild disease, with 616 fatal human cases. Despite poultry vaccination, H7N9 has not been eradicated. Previously we demonstrated increased pathogenesis in turkeys infected with H7N9, correlating with the emergence of the L217Q (L226Q H3 numbering) polymorphism in the haemagglutinin (HA) protein. A Q217 containing virus also arose and is now dominant in China following vaccination. We compared infection and transmission of this Q217 containing turkey-adapted (ty-ad) isolate alongside the H7N9 (L217) wild-type (wt) virus in different poultry species, and investigated the zoonotic potential in the ferret model. Both wt and ty-ad viruses demonstrated similar shedding and transmission in turkeys and chickens. However, the ty-ad virus was significantly more pathogenic than the wt virus in turkeys but not in chickens, causing 100% and 33% mortality in turkeys respectively. Expanded tissue tropism was seen for the ty-ad virus in turkeys but not chickens, yet the viral cell receptor distribution was broadly similar in visceral organs of both species. The ty-ad virus required exogenous trypsin for in vitro replication yet had increased replication in primary avian cells. Replication was comparable in mammalian cells and the ty-ad virus replicated successfully in ferrets. The L217Q polymorphism also affected antigenicity. Therefore, H7N9 infection in turkeys can generate novel variants with increased risk through altered pathogenicity and potential HA antigenic escape. These findings emphasise the requirement for enhanced surveillance and understanding of A/Anhui/1/13-lineage viruses and their risk to different species.

microbiology↗

bioRxiv2024

Rapid mortality in captive bush dogs (Speothos venaticus) caused by influenza A of avian origin (H5N1) at a wildlife collection in the United Kingdom

Europe has suffered unprecedented epizootics of high pathogenicity avian influenza (HPAI) clade 2.3.4.4b H5N1 since Autumn 2021. As well as impacting upon commercial and wild avian species, the virus has also infected mammalian species more than ever observed previously. Mammalian species involved in spill over events have primarily been scavenging terrestrial carnivores and farmed mammalian species although marine mammals have also been affected. Alongside reports of detections in mammalian species found dead through different surveillance schemes, several mass mortality events have been reported in farmed and wild animals. During November 2022, an unusual mortality event was reported in captive bush dogs (Speothos venaticus) with clade 2.3.4.4b H5N1 HPAIV of avian origin being the causative agent. The event involved an enclosure of fifteen bush dogs, ten of which succumbed during a nine-day period with some dogs exhibiting neurological disease. Ingestion of infected meat is proposed as the most likely infection route.

microbiology↗

bioRxiv2024

Utilising citizen science data to rapidly assess potential wild bridging hosts and reservoirs of infection: avian influenza outbreaks in Great Britain

High pathogenicity avian influenza virus (HPAIV) is a rapidly evolving orthomyxovirus causing significant economic and environmental harm. Wild birds are a key reservoir of infection and an important source of viral incursions into poultry populations. However, we lack thorough understanding of which wild species drive incursions and whether this changes over time. We explored associations between abundances of 152 avian species and cases of HPAI in poultry premises across Great Britain between October-2021 and January-2023. Spatial generalised additive models were used, with species abundance distributions sourced from eBird modelled predictions. Associations were investigated at the species-specific level and across aggregations of species. During autumn/winter, associations were generally strongest with waterbirds such as ducks and geese; however, we also found significant associations in other groups such as non-native gamebirds, and rapid change in species-specific associations over time. Our results demonstrate the value of citizen science in rapid exploration of wild reservoirs of infection as facilitators of disease incursion into domestic hosts, especially in regions where surveillance programmes in wild birds are absent. This can be a critical step towards improving species-specific biosecurity measures and targeted surveillance; particularly for HPAIV, which has undergone sudden shifts in host-range and continues to rapidly evolve.

ecology↗

bioRxiv2023

Detection and spread of high pathogenicity avian influenza virus H5N1 in the Antarctic Region

Until recent events, the Antarctic was the only major geographical region in which high pathogenicity avian influenza virus (HPAIV) had never previously been detected. The current panzootic of H5N1 HPAIV has decimated wild bird populations across Europe, North America, and South America. Here we report on the detection of clade 2.3.4.4b H5N1 HPAIV in the Antarctic and sub-Antarctic regions of South Georgia and the Falkland Islands, respectively. We initially detected H5N1 HPAIV in samples collected from brown skuas at Bird Island, South Georgia on 8th October 2023. Since this detection, mortalities were observed in brown skuas, kelp gulls, South Georgia shag, Antarctic tern, elephant seals and fur seals at multiple sites across South Georgia. Subsequent testing confirmed H5N1 HPAIV across several sampling locations in multiple avian species and two seal species. Simultaneously, we also confirmed H5N1 HPAIV in southern fulmar and black-browed albatross in the Falkland Islands. Genetic assessment of the virus indicates spread from South America, likely through movement of migratory birds. Critically, genetic assessment of sequences from mammalian species demonstrates no increased risk to human populations. Here we describe the detection, species impact and genetic composition of the virus and propose both introductory routes and potential long-term impact on avian and mammalian species across the Antarctic region. We also speculate on the threat to specific populations following recent reports in the area.

microbiology↗