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In Africa, livestock production plays a crucial role for sustainable food security and economic growth. However, the development of this sector has been delayed by livestock diseases, one of the main constraints, which can cause important production and economic losses. To overcome these constraints, farmers extensively use antimicrobials, which in turn can lead to antimicrobial resistance (AMR), one of the main threats to global health and food security. Biosecurity has been identified as a key strategy to reduce livestock diseases. Therefore, the current systematic review and meta‐analysis, conducted according to the Cochrane guideline, aimed at determining the efficacy of biosecurity in preventing and controlling infectious diseases in livestock farms in Africa. Of the 1408 records retrieved from five different databases, only 16 met the inclusion criteria. These studies were conducted in Egypt (31.2%), Nigeria (31.2%), Uganda (18.8%), Ethiopia (12.5%) and Tunisia (6.3%) and concerned poultry (62.4%), pigs (18.8%) and cattle (18.8%). Investigations focused mainly on avian influenza (AI) (15.0%) and coccidiosis (10.0%) in poultry and African swine fever (ASF) (10.0%) in pigs. In poultry farms, the results of the pairwise meta‐analysis showed that biosecurity measures related to visitors and farmworkers could be effective at reducing the risk of introduction and spread of AI viruses (odds ratio [OR] = 0.48; 95% confidence interval [CI] 0.28–0.82). Moreover, inadequate biosecurity seemed to be a factor promoting coccidiosis (OR = 4.20; 95% CI 2.4–7.4) and AI (OR = 1.74; 95% CI 1.23–2.48). Prevention of ASF was significantly associated with the application of biosecurity measures related to animals' transport, removal of carcasses and manure (OR = 0.33; 95% CI 0.12–0.88). Despite their importance, these findings cannot be translated to the entire African continent, since no studies were available for more than 90% of its countries. More research should be carried out to fill in the gaps identified by this review. [ABSTRACT FROM AUTHOR]

H5 influenza is considered a potential pandemic threat. Recently, H5 viruses belonging to clade 2.3.4.4b have caused large outbreaks in avian and multiple nonhuman mammalian species. Previous studies have identified molecular phenotypes of the viral hemagglutinin (HA) protein that contribute to pandemic potential in humans, including cell entry, receptor preference, HA stability, and reduced neutralization by polyclonal sera. However, prior experimental work has only measured how these phenotypes are affected by a handful of the >10,000 different possible amino-acid mutations to HA. Here, we use pseudovirus deep mutational scanning to measure how all mutations to a 2.3.4.4b H5 HA affect each phenotype. We identify mutations that allow HA to better bind α2-6-linked sialic acids and show that some viruses already carry mutations that stabilize HA. We also measure how all HA mutations affect neutralization by sera from mice and ferrets vaccinated against or infected with 2.3.4.4b H5 viruses. These antigenic maps enable rapid assessment of when new viral strains have acquired mutations that may create mismatches with candidate vaccine virus, and we show that a mutation present in some recent H5 HAs causes a large antigenic change. Overall, the systematic nature of deep mutational scanning combined with the safety of pseudoviruses enables comprehensive measurements of the phenotypic effects of mutations that can inform real-time interpretation of viral variation observed during surveillance of H5 influenza. H5 influenza is considered a potential pandemic threat. Using deep mutational scanning, this work reveals how the >10,000 different possible amino-acid mutations in hemagglutinin affect cell entry, receptor preference, protein stability and neutralization by antibodies, which can inform real-time interpretation of viral mutations observed during surveillance of H5 influenza. [ABSTRACT FROM AUTHOR]

A high pathogenicity avian influenza (HPAI) subtype H7N6 virus emerged in South African poultry in 2023 and later spread to Mozambique, the first documented emergence of H7 HPAI in the African continent. A total of 6.82 million birds succumbed to the disease or were culled, representing about 20% of the South African egg‐laying flock and almost 30% of the broiler breeder flock. The complete genomes of 68 outbreak viruses were sequenced and analyzed, tracing the phylogenetic origins of the ancestral H7N6 virus to a reassortment of various subtypes that circulated in southern African wild birds. Molecular clock analysis determined that the virus emerged in the first week of May 2023, probably in a smallholder chicken flock, before spreading to commercial farms, where the disease was first reported in early June. The multibasic hemagglutinin protein cleavage site (HA0) was derived from a nonhomologous recombination event with chicken 28S ribosomal ribonucleic acid (RNA). Few genetic markers associated with an increased risk to humans were present in the translated viral proteins. The intravenous pathogenicity index (IVPI) value of the index case isolate was 1.67, reflecting that 50% of the specific pathogen‐free chickens died within 4 days of infection. Surviving birds showing mostly mild clinical signs and recovered by day 10 postinfection. Prior to death, chickens shed the virus primarily through the respiratory route, with lower amounts shed from the cloaca, but in the survivors, the virus was still being shed from the cloaca on day 10. Fomites were the likely source of disease spread between farms, and the amount of H7N6 HPAI virus per gram of feces was calculated at ~383,193 (5.58 log10) egg infectious dose 50 (EID50) equivalents, chicken feather follicles contained on average 739,712.43 (5.87 log10) EID50 equivalents, and 20 µg of feather dust contained 14,976.96 (4.175 log10) EID50 equivalents. [ABSTRACT FROM AUTHOR]

Since April 2024, sporadic infections with highly pathogenic avian influenza (HPAI) A(H5) viruses have been detected among dairy farm workers in the United States. To date, infections have mostly been detected through worker monitoring, and have been mild despite the possibility of more severe illness. During June–August 2024, CDC collaborated with the Michigan Department of Health and Human Services and the Colorado Department of Public Health and Environment to implement cross-sectional serologic surveys to ascertain the prevalence of recent infection with HPAI A(H5) virus among dairy workers. In both states, a convenience sample of persons who work in dairies was interviewed, and blood specimens were collected. Among 115 persons, eight (7%; 95% CI = 3.6%–13.1%) had serologic evidence of recent infection with A(H5) virus; all reported milking cows or cleaning the milking parlor. Among persons with serologic evidence of infection, four recalled being ill around the time cows were ill; symptoms began before or within a few days of A(H5) virus detections among cows. This finding supports the need to identify and implement strategies to prevent transmission among dairy cattle to reduce worker exposures and for education and outreach to dairy workers concerning prevention, symptoms, and where to seek medical care if the workers develop symptoms. Timely identification of infected herds can support rapid initiation of monitoring, testing, and treatment for human illness, including mild illness, among exposed dairy workers. [ABSTRACT FROM AUTHOR]

The risk for transmission of highly pathogenic avian influenza A(H5N1) virus from dairy cows to humans is currently low; however, personal protective equipment (PPE) use during work activities on dairy farms has not been well described. PPE use can protect farmworkers when they are working with highly pathogenic avian influenza A(H5N1)–infected cows. The Colorado Department of Public Health and Environment (CDPHE) and the Colorado Department of Agriculture (CDA) offered PPE to all Colorado farms before or during an A(H5N1) outbreak in cows in 2024. CDPHE surveyed 83 dairy workers from three farms with a confirmed bovine A(H5N1) outbreak. Frequently reported farm worker activities included milking cows or working in the milking parlor (51%), cleaning cow manure (49%), and transporting cows (46%). Frequently reported PPE items available to workers before A(H5N1) outbreaks included gloves (88%), eye protection (e.g., safety glasses or goggles) (76%), rubber boots or boot covers (71%), and head covers (69%). N95 respirator use was low among workers who were exposed to ill cows after detection of A(H5N1) virus (26%). PPE use while working with ill cows increased a mean of 28% after detection of A(H5N1) virus on surveyed farms; use of eye protection while milking cows increased the most (40%). Public health PPE distribution, education, and collaboration with CDA might have increased PPE use on dairy farms with A(H5N1) virus–infected cows and mitigated risk for farmworkers acquiring A(H5N1) virus. [ABSTRACT FROM AUTHOR]

Currently A(H5Nx) avian influenza viruses are globally widespread and continue to evolve. Since their emergence in 2020 novel highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b reassortant viruses have become predominant in the world and caused multiple infections in mammals. It was shown that some of A(H5N1) viruses mostly isolated from mammals contain an E627K mutation in the PB2 protein which can lead to adaptation of influenza viruses to mammalian cells. In 2023 in Russia we have isolated two highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b viruses from birds one of which contained an E627K mutation in the PB2 protein. This virus had increased virulence in mice. Limited airborne transmission of the virus with the PB2-E627K mutation was observed between ferrets, in which infectious virus was detected in the nasal washings of the three of the twelve recipient ferrets, and clinical symptoms of the disease were observed in one case. Both viruses showed dominant binding to avian-type sialoside receptors, which was most likely the reason for the limited transmissibility. Thus, this study indicates a possible limited increase in the pandemic potential of A(H5N1) 2.3.4.4b viruses and highlights the importance of continuous avian influenza surveillance for pandemic preparedness and response. [ABSTRACT FROM AUTHOR]

Avian influenza viruses (AIVs) are a major economic burden to the poultry industry and pose serious zoonotic risks, with human infections being reported every year. To date, the vaccination of birds remains the most important method for the prevention and control of AIV outbreaks. Most national vaccination strategies against AIV infection use whole virus-inactivated vaccines, which predominantly trigger a systemic antibody-mediated immune response. There are currently no studies that have examined the antibody repertoire of birds that were infected with and/or vaccinated against AIV. To this end, we evaluate the changes in the H9N2-specific IgM and IgY repertoires in chickens subjected to vaccination(s) and/or infectious challenge. We show that a large proportion of the IgM and IgY clones were shared across multiple individuals, and these public clonal responses are dependent on both the immunisation status of the birds and the specific tissue that was examined. Furthermore, the analysis revealed specific clonal expansions that are restricted to particular H9N2 immunisation regimes. These results indicate that both the nature and number of immunisations are important drivers of the antibody responses and repertoire profiles in chickens following H9N2 antigenic stimulation. We discuss how the repertoire biology of avian B-cell responses may affect the success of AIV vaccination in chickens, in particular the implications of public versus private clonal selection. [ABSTRACT FROM AUTHOR]

The guinea fowl (Numida meleagris) holds significant agricultural importance in Ghana, particularly in the Northern, Upper East and Upper West Regions. Despite their economic and cultural significance, guinea fowls face a potential threat from avian influenza, a global concern for its adverse impact on poultry populations. This study assessed the seroprevalence of the virus in mature guinea fowls in the Upper East Region. A cross‐sectional survey was conducted in three districts within the Upper East Region from April to June 2023. Blood samples were collected from 397 guinea fowls that are over 4 weeks old, and seroprevalence was determined using ID Screen Influenza A Antibody Competition Enzyme‐linked immunosorbent assay (ELISA). The study analysed demographic factors such as sex, age and source of birds, employing statistical methods to establish associations. Among the sampled guinea fowls, 24.7% tested positive for avian influenza antibodies, whereas 75.3% were seronegative. Age did not show statistically significant associations with seroprevalence, but intriguing patterns were observed. Adult guinea fowls exhibited higher seroprevalence (23.7%) compared to growers (1.0%). The source of birds showed no significant association, but birds from slaughter points demonstrated higher seroprevalence (11.6%) compared to households (5.0%) and live bird markets (8.1%). In conclusion, the study underscores the importance of monitoring avian influenza in guinea fowls to implement effective control measures. The presence of antibodies suggests guinea fowls may contribute to virus transmission in the Upper East Region. The study recommends ongoing nationwide surveillance to assess the true prevalence of avian influenza in guinea fowls across Ghana. [ABSTRACT FROM AUTHOR]

Avian species have played a pivotal role in developmental hematopoiesis research, leading to numerous critical discoveries. Avian influenza, particularly the H5N1 strain, poses a significant threat to poultry and has zoonotic potential for humans. Infections often result in abnormal hematologic profiles, highlighting the complex interplay between avian diseases and hematopoiesis. Many avian diseases can suppress immune cells in the bone marrow (BM), impacting immune responses. Studying hematopoietic stem cells (HSCs) in avian BM is crucial for understanding these processes and developing effective vaccines and protection strategies for both avian and human health. This study adapted methods from mouse studies to isolate avian HSCs as Lineage-negative (Lin-) cells. These isolated cells were further identified as Lin-Sca1+c-Kit+ (LSK) and were found to be more prevalent than in control groups. RT-PCR analyses were conducted, showing that genes like MEIS1 and TSC1 were upregulated, while SIRT1, FOXO1, and AHR were downregulated in these stem cells. Screening for LSK markers revealed ten unique surface antigens in the Sca1+c-Kit+ cell populations, including highly enriched antigens such as CD178, CD227, and CD184. Additionally, studies on quail HSCs demonstrated that similar labeling techniques were effective in quail BM. The research demonstrated that the identification of avian HSC-specific surface antigens provides valuable insights into the pathogenesis of avian influenza and other diseases, enhancing our understanding of how these diseases suppress HSC function. Notably, the upregulation of MEIS1 and TSC1 genes in LSK cells underscores their critical roles in regulating hematopoietic processes. Conversely, the downregulation of SIRT1, FOXO1, and AHR genes provides important clues about their roles in differentiation and immune response mechanisms. The findings of this study deepen our understanding of the effects of avian diseases on the immune system by identifying surface markers specific to avian HSCs. The suppression of HSC function by pathogens such as influenza highlights the importance of understanding these cells in developing targeted vaccines. These results represent a significant step towards improving global health security by mitigating risks associated with avian pathogens. [ABSTRACT FROM AUTHOR]

Animal movement and population connectivity are key areas of uncertainty in efforts to understand and predict the spread of infectious disease. The emergence of highly pathogenic avian influenza (HPAI) in South America poses a significant threat to globally significant populations of colonial breeding marine predators in the South Atlantic. Yet, there is a poor understanding of which species or migratory pathways may facilitate disease spread. Compiling one of the largest available animal tracking datasets in the South Atlantic, we examine connectivity and inter‐population mixing for colonial breeding marine predators tagged at the Falkland Islands. We reveal extensive connectivity for three regionally dominant and gregarious species over the Patagonian Shelf. Black‐browed albatrosses (BBA), South American fur seals (SAFS) and Magellanic penguins (MAG) used coastal waters along the Atlantic coast of South America (Argentina and Uruguay). These behaviours were recorded at or in close proximity to breeding colonies and haul‐out areas with dense aggregations of marine predators. Transit times to and from the Falkland Islands to the continental coast ranged from 0.2–70 days, with 84% of animals making this transit within 4 days ‐ a conservative estimate for HPAI infectious period. Our findings demonstrate BBA, SAFS and MAG connectivity between the Falkland Islands and mainland South America over an expansive spatial network and numerous pathways, which has implications for infectious disease persistence, transmission and spread. This information is vital in supporting HPAI disease surveillance, risk assessment and marine management efforts across the region. [ABSTRACT FROM AUTHOR]

The article examines the current status of H5N1 avian influenza, emphasizing its low risk to humans despite widespread animal infections. Topics discussed include the virus's spread among wild and domestic animals, potential for mammalian transmission, and the importance of monitoring and managing risks to prevent human infection.

Background: H9N2 avian influenza viruses have been circulating in Bangladesh since 2006, affecting multiple avian species and resulting in economic losses. The recent emergence of tribasic strains, along with co-infections, has increased the risk to poultry health. Therefore, the study aimed to compare the immune responses of Sonali (crossbred) and commercial broiler chickens infected with tribasic H9N2 low pathogenic avian influenza (LPAI) virus. Methods: Following H9N2 infection, proinflammatory (IL-6, IL-8, IL-1β and TNF-α) and antiviral (IFN-β and IFN-γ) cytokine expressions were observed in the trachea, lungs, intestine, and lymphoid tissues in Sonali and broiler chickens from 1 day post infection (dpi) to 10 dpi by qPCR. Results: Sonali chickens exhibited significantly higher proinflammatory and antiviral cytokine expressions in the trachea at 3–7 days post infection (dpi), while broiler chickens showed lower immune responses. Broiler chickens displayed prolonged IL-6, IL-8, and IL-1β expression in lungs at 3–10 dpi compared to Sonali chickens. In the intestine, broiler chickens showed higher IL-6 and IL-8 expression that peaks at 1–3 dpi, while in Sonali chickens only IL-1β elevated at 10 dpi. In response to the H9N2 viruses, broiler chickens exhibited a stronger early IFN-β responses and a delayed IFN-γ responses in their lymphoid organs compared to Sonali chickens. Conclusion: This suggests distinct immune profiles between the chicken types in response to the H9N2 infection. The information sheds light on the function of innate immunity in the pathophysiology of currently circulating tribasic H9N2 virus and could assist in effective controlling of avian influenza virus spread in poultry and designing vaccines. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza A(H5N1) detected in dairy cows raises concerns about milk safety. The effects of pasteurization-like temperatures on influenza viruses in retail and unpasteurized milk revealed virus resilience under certain conditions. Although pasteurization contributes to viral inactivation, influenza A virus, regardless of strain, displayed remarkable stability in pasteurized milk. [ABSTRACT FROM AUTHOR]

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Since its first isolation from migratory birds in Egypt in 2016, highly pathogenic avian influenza (HPAI) H5N8 has caused several outbreaks among domestic poultry in various areas of the country affecting poultry health and production systems. However, the genetic and biological properties of the H5N8 HPAI viruses have not been fully elucidated yet. In this study, we aimed to monitor the evolution of circulating H5N8 viruses and identify the pathogenicity and mammalian adaptation in vitro and in vivo. Three H5N8 HPAI viruses were used in this study and were isolated in 2021–2022 from poultry and wild birds during our routine surveillance. RNA extracts were subjected to full genome sequencing. Genetic, phylogenetic, and antigenic analyses were performed to assess viral characteristics and similarities to previously isolated viruses. Phylogenetic analysis showed that the hemagglutinin genes of the three isolates belonged to clade 2.3.4.4b and grouped with the 2019 viruses from G3 with high similarity to Russian and European lineages. Multiple basic amino acids were observed at cleavage sites in the hemagglutinin proteins of the H5N8 isolates, indicating high pathogenicity. In addition, several mutations associated with increased virulence and polymerase activity in mammals were observed. Growth kinetics assays showed that the H5N8 isolate is capable of replicating efficiently in mammalian cells lines. In vivo studies were conducted in SPF chickens (White Leghorn), mice, and hamsters to compare the virological characteristics of the 2022 H5N8 isolates with previous H5N8 viruses isolated in 2016 from the first introduction. The H5N8 viruses caused lethal infection in all tested chickens and transmitted by direct contact. However, we showed that the 2016 H5N8 virus causes a higher mortality in chickens compared to 2022 H5N8 virus. Moreover, the 2022 virus can replicate efficiently in hamsters and mice without preadaptation causing systemic infection. These findings underscore the need for continued surveillance of H5 viruses to identify circulating strains, determine the commercial vaccine's effectiveness, and identify zoonotic potential. [ABSTRACT FROM AUTHOR]

Influenza virus pandemics are caused by viruses from animal reservoirs that adapt to efficiently infect and replicate in human hosts. Here, we investigate whether Interferon-Induced Transmembrane Protein 3 (IFITM3), a host antiviral factor with known human deficiencies, plays a role in interspecies virus infection and adaptation. We find that IFITM3-deficient mice and human cells can be infected with low doses of avian influenza viruses that fail to infect WT counterparts, identifying a new role for IFITM3 in controlling the minimum infectious virus dose threshold. Remarkably, influenza viruses passaged through Ifitm3−/− mice exhibit enhanced host adaptation, a result that is distinct from viruses passaged in mice deficient for interferon signaling, which exhibit attenuation. Our data demonstrate that IFITM3 deficiency uniquely facilitates potentially zoonotic influenza virus infections and subsequent adaptation, implicating IFITM3 deficiencies in the human population as a vulnerability for emergence of new pandemic viruses. This study highlights that IFITM3 deficiency lowers the minimum infectious dose of influenza virus, enhances adaptation of influenza viruses to a new host species, and broadly increases infection of human cells by avian and swine influenza viruses. [ABSTRACT FROM AUTHOR]

A/goose/Guangdong/1/96-like (GsGd) highly pathogenic avian influenza (HPAI) H5 viruses cause severe outbreaks in poultry when introduced. Since emergence in 1996, control measures in most countries have suppressed local GsGd transmission following introductions, making persistent transmission in domestic birds rare. However, geographical expansion of clade 2.3.4.4 sublineages has raised concern about establishment of endemic circulation, while mechanistic drivers leading to endemicity remain unknown. We reconstructed the evolutionary history of GsGd sublineage, clade 2.3.4.4c, in Taiwan using a time-heterogeneous rate phylogeographic model. During Taiwan's initial epidemic wave (January 2015 - August 2016), we inferred that localised outbreaks had multiple origins from rapid spread between counties/cities nationwide. Subsequently, outbreaks predominantly originated from a single county, Yunlin, where persistent transmission harbours the trunk viruses of the sublineage. Endemic hotspots determined by phylogeographic reconstruction largely predicted the locations of re-emerging outbreaks in Yunlin. The transition to endemicity involved a shift to chicken-dominant circulation, following the initial bidirectional spread between chicken and domestic waterfowl. Our results suggest that following their emergence in Taiwan, source-sink dynamics from a single county have maintained GsGd endemicity up until 2023, pointing to where control efforts should be targeted to eliminate the disease. Highly pathogenic H5 avian influenza viruses of the A/Goose/Guangdong/96-like lineage spread globally and have become endemic in some locations. Here, the authors perform phylogenetic analyses to describe the dynamics of this lineage as it transitioned from causing sporadic outbreaks to becoming endemic in Taiwan. [ABSTRACT FROM AUTHOR]

The incidence of human infection by zoonotic avian influenza viruses, especially H5N1 and H7N9 viruses, has increased. Current zoonotic H7N9 avian influenza viruses (identified since 2013) emerged during reassortment of viruses belonging to different subtypes. Despite analyses of their genetic background, we do not know why current H7N9 viruses are zoonotic. Therefore, there is a need to identify the factor(s) responsible for the extended host tropism that enables these viruses to infect humans as well as birds. To identify H7N9-specific amino acids that confer zoonotic properties on H7N9 viruses, we performed multiple alignment of the hemagglutinin (HA) amino acid sequences of A/Shanghai/1/2013 (H7N9) and A/duck/Zhejiang/12/2011(H7N3) (a putative, non- or less zoonotic HA donor to the zoonotic H7N9 virus). We also analyze the function of an H7N9 HA-specific amino acid with respect to HA acid stability, and evaluated the effect of acid stability on viral infectivity and virulence in a mouse model. HA2-116D, preserved in current zoonotic H7N9 viruses, was crucial for loss of HA acid stability. The acid-labile HA protein in H7 viruses played an important role in infection of human airway epithelial cells; HA2-116D contributed to infection and replication of H7 viruses. Finally, HA2-116D served as a H7 virulence factor in mice. These results suggest that acid-labile HA harboring HA2-116D confers zoonotic characteristics on H7N9 virus and that future novel zoonotic avian viruses could emerge from non-zoonotic H7 viruses via acquisition of mutations that remove HA acid stability. Author summary: Despite detailed analyses of the genetic background, we do not know why H7N9 avian influenza viruses circulating since 2013 behave as zoonotic viruses. Here, we (i) identified a specific amino acid, HA2-116D, in the HA protein that confers zoonotic properties on the H7N9 virus; (ii) show that HA2-116D plays an important role in viral infectivity and replication in human airway epithelial cells through its ability to increase pH sensitivity, which readily induces viral-cell membrane fusion in host cells and subsequent infection; (iii) show that HA2-116D is not usually present in the HA protein of H7 viruses with low zoonotic potential; and (iv) show that HA2-116D increases the virulence of the H7 virus in mice. These results suggest that acid-labile HA is an important factor underlying efficient infection of human airway epithelial cells, as well as a virulence factor for mammalian hosts, and that novel zoonotic avian viruses could emerge from non-zoonotic H7 viruses that acquire mutations resulting in loss of HA acid stability. [ABSTRACT FROM AUTHOR]

The highly pathogenic avian influenza 2.3.4.4b H5 viruses have been a cause for concern recently, as they have been responsible for continuous outbreaks since 2021. In China, the H5N6 subtype has been predominantly circulating in domestic poultry but has rarely been detected in wild birds over the past 3 years. In December 2023, novel reassortant 2.3.4.4b H5N6 viruses were resurgent in wild birds and domestic ducks in Eastern Asia. The viruses were reassorted with those of currently prevalent 2.3.4.4b H5N1 viruses of wild bird origin worldwide, as well as the H5N6 viruses that caused human infections in 2022 and low pathogenic avian influenza viruses, such as the H9N2 virus, which also contributed internal gene to the novel H5N6 viruses. Based on the phylogenetic analyses, we inferred that this recombination process occurred in migratory breeding sites in early 2023. Given the rapid transmission and high mutation capacity of currently circulating H5N1 viruses, as well as the strong pathogenicity of H5N6 viruses to humans, the novel recombinant viruses may continue to evolve and pose new threats to human health. Therefore, continuous surveillance of H5N6 viruses in wild birds and domestic poultry should be strengthened. [ABSTRACT FROM AUTHOR]

The article discusses the potential for the H5N1 bird flu virus to cause a human pandemic. It highlights the recent outbreak of the H5N1 virus in cattle, its evolution, and its ability to infect various species. The article also explores the genetic traits needed for efficient human transmission and uses a chaos theory logistic map to assess the likelihood of a pandemic. While the virus has shown some concerning features, the authors believe that the risk of a pandemic caused by H5N1 is currently low. The article emphasizes the importance of continued monitoring, vaccination strategies, and global collaboration to mitigate the potential impact of the virus. [Extracted from the article]

Cases of H5 highly pathogenic avian influenzas (HPAI) are on the rise. Although mammalian spillover events are rare, H5N1 viruses have an estimated mortality rate in humans of 60%. No human cases of H5 infection have been reported in Malaysian Borneo, but HPAI has circulated in poultry and migratory avian species transiting through the region. Recent deforestation in coastal habitats in Malaysian Borneo may increase the proximity between humans and migratory birds. We hypothesise that higher rates of human-animal contact, caused by this habitat destruction, will increase the likelihood of potential zoonotic spillover events. In 2015, an environmentally stratified cross-sectional survey was conducted collecting geolocated questionnaire data in 10,100 individuals. A serological survey of these individuals reveals evidence of H5 neutralisation that persisted following depletion of seasonal H1/H3 HA binding antibodies from the plasma. The presence of these antibodies suggests that some individuals living near migratory sites may have been exposed to H5 HA. There is a spatial and environmental overlap between individuals displaying high H5 HA binding and the distribution of migratory birds. We have developed a novel surveillance approach including both spatial and serological data to detect potential spillover events, highlighting the urgent need to study cross-species pathogen transmission in migratory zones. Spillover of avian influenza H5N1 from birds to mammals have been increasingly detected, but reports of cases in humans remain limited. Here, the authors find serological evidence of human exposure to influenza H5N1 in Malaysian Borneo, an important stopover site for migratory shorebirds. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza (HPAI) H5 viruses from different clades have been circulating globally, threatening wild/domestic birds and mammals. Given frequent spillovers and high mortality among mammals, coupled with our inability to predict which clade of H5 virus has pandemic potential, cross-clade protective HPAI H5 vaccines are urgently needed. Here, we demonstrate the applicability of a lipid nanoparticle-based mRNA vaccine modality to induce cross-protective immunity against lethal HPAI virus infection. [ABSTRACT FROM AUTHOR]

We characterized 15 H5N1 HPAI viruses from different small- and medium-scale poultry flocks across Bangladesh during 2018–2021 based on their complete genome sequences. The antigenic relatedness of H5N1 HPAI viruses from different timepoints was analysed. During 2020–2021, 42.11% of the flocks tested positive for at least one of the respiratory infections, with 15.79% showing influenza A virus, of which 8.77% tested positive for HPAIV H5N1. Co-infections with two to four pathogens were detected in 15.8% of flocks. Phylogeny and gene constellation analyses based on complete genome sequences of 15 HPAI viruses revealed the continuing circulation of H5 clade 2.3.2.1a genotype G2 viruses. In the HA protein of the study isolates, functionally meaningful mutations caused the loss of an N-linked glycosylation site (T156A), a modified antigenic site A (S141P), and a mutation in the receptor binding pocket (E193R/K). Consequently, antigenic analysis revealed a significant loss of cross-reactivity between viruses from different host species and periods. Most viruses displayed oseltamivir resistance markers at positions V96, I97, S227, and N275 (N1 numbering) of the NA protein. In addition, for the PB2, M1, and NS1 proteins, significant mutations were noticed that have been associated with polymerase activity and increased virulence for mammals in all study isolates. These results highlight the need for intensified genomic surveillance of HPAI circulating in poultry in Bangladesh and for establishing appropriate control measures to decrease the circulation of these viruses in poultry in the country. [ABSTRACT FROM AUTHOR]

This document is a compilation of references related to the outbreak of avian influenza, specifically the H5N1 strain, in different regions worldwide. It includes scientific articles, reports, and studies discussing the spread of the virus among wild birds, marine mammals, and other animals. The references also cover the impact of the virus on various species and ecosystems, as well as efforts to control and prevent its spread. Researchers and library patrons interested in studying the avian influenza outbreak and its effects on wildlife will find valuable information in these references. Additionally, the document includes references to topics such as marine mammal ecotoxicology, the conservation of Galápagos birds, the prevention and control of highly pathogenic avian influenza, and Ecuador's preparedness and response to the COVID-19 pandemic. [Extracted from the article]

Background and Aim: Avian influenza is a global threat to avian species, particularly in developing countries. Recombinant vaccines, including virus-like particles (VLPs), are promising strategies for preventing the spread of the disease. VLPs produced through the self-assembly of viral structural proteins without genomic material mimic native virions and are promising platforms for new vaccines. VLPs have been shown to elicit protective antibodies and are effective and safe vaccines against influenza. This study aimed to optimize the protocol for the production and characterization of H9N2 VLPs and their evaluation as a vaccine in broiler birds. Materials and Methods: Low-pathogenic influenza virus (LPAI) H9N2 was isolated and characterized through wholegenome sequencing, and a VLP-based vaccine for LPAI H9N2 was prepared using a baculovirus expression system. Codon-optimized hemagglutinin (HA), neuraminidase (NA), and M1 were successfully cloned in pFastbac1 and expressed in SF9 cells. Proteins were characterized using sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE), western blotting, and electron microscopy after purification. Semi-purified proteins were tested as a vaccine in broiler chickens challenged with LPAI H9N2. Results: Recombinant Bacmid DNA from positive clones was extracted and confirmed using a polymerase chain reaction. The transfection showed cytopathic effects, and the proteins were confirmed through western blotting and SDS-PAGE, which showed the sizes of HA = 62-64 KD, NA = 52 KD, and M1 = 25 KD. The shape and morphology were confirmed through transmission electron microscopy which revealed 100-150 nm size particles. As a result, the semi-purified VLPs (HA assay: 256) were tested as a vaccine for specific-pathogen free broiler birds; administered through subcutaneous and intranasal routes. The birds were challenged on the 28th day after vaccination with the H9N2 strain, and the birds showed significant cross-reactivity with the H9N2 strain. Conclusion: The semi-purified VLP-based vaccine induced a significant immune response in vivo. This vaccine formulation has the potential to control avian influenza outbreaks in Pakistan's poultry industry. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza (HPAI) viruses pose a significant threat to both poultry and wild bird populations. Migratory wild birds play a key role in the intercontinental spread of avian influenza (AI), introducing the virus into poultry populations. In response to frequent AI outbreaks in Europe, the European Food Safety Authority (EFSA), at the request of the European Commission (EC), produces quarterly and annual epidemiological reports to monitor and analyse AI trends. A key component of this surveillance includes the integration of outbreak data from Member States and contributions from non‐governmental ornithological organisations like the European Bird Census Council (EBCC) and the European Union for Bird Ringing (EURING) together in a predictive spatio‐temporal risk assessment model. Previous data integration and modelling efforts led to the development of an early warning system for predicting HPAI outbreaks accessible through a publicly available online user interface: the Bird Flu Radar. This report presents an improvement of the system by expanding the species coverage and refining the existing base models behind the epidemiological model. Specifically, this report details the exploration to incorporate 12 additional wild bird species into the models, and the changes made to the base models predicting the distribution and movements of wild birds. We demonstrate the improvements respecting the existing base models while at the same time enhancing the effectiveness in predicting HPAI outbreaks and possibly mitigating negative effects in Europe by providing more accurate predictions to different stakeholders. [ABSTRACT FROM AUTHOR]

Between 15 June and 20 September 2024, 75 highly pathogenic avian influenza (HPAI) A(H5) and A(H7) virus detections were reported in domestic (16) and wild (59) birds across 11 countries in Europe. Although the overall number of detections in Europe continued to be low compared to previous epidemiological years, an increase in cases along the Atlantic, North Sea and Baltic coasts was notable, particularly an increase in the detection of HPAI viruses in colony‐breeding seabirds. Besides EA‐2022‐BB and other circulating genotypes, these detections also included EA‐2023‐DT, a new genotype that may transmit more efficiently among gulls. In Germany, HPAI A(H7N5) virus emerged in a poultry establishment near the border with the Netherlands. No new HPAI virus detections in mammals were reported in Europe during this period, but the number of reportedly affected dairy cattle establishments in the United States of America (USA) rose to >230 in 14 states, and HPAI virus was identified in three new mammal species. Between 21 June and 20 September 2024, 19 new human cases with avian influenza virus infection were reported from the USA (six A(H5N1) cases and five A(H5) cases), Cambodia (five A(H5N1) cases, including one fatal), China (one fatal A(H5N6) case and one A(H9N2) case), and Ghana (one A(H9N2) case). Most of the human cases (90%, n = 17/19) had reported exposure to poultry, live poultry markets, or dairy cattle prior to avian influenza virus detection or onset of illness. Human infections with avian influenza viruses remain rare and no evidence of human‐to‐human transmission has been documented in the reporting period. The risk of infection with currently circulating avian A(H5) influenza viruses of clade 2.3.4.4b in Europe remains low for the general public in the European Union/European Economic Area (EU/EEA). The risk of infection remains low‐to‐moderate for those occupationally or otherwise exposed to infected animals or contaminated environments. [ABSTRACT FROM AUTHOR]

Avian influenza outbreaks are recurring worldwide. In Norwegian and Danish media, fluctuating attention has been paid to these outbreaks and the coverage that exists largely portrays the situation as a distant problem, limited to so-called non-Western countries. In the present article, we have analysed news articles from two Norwegian and two Danish newspapers published in 2006/2008, 2017 and 2021 using Critical Discourse Analysis (CDA). By analysing linguistic articulations of risk and blame for avian influenza in Norwegian and Danish media, we explore how this portrayal creates discursive distinctions between risk and blame 'here' in Europe and 'there' in Asian and African countries. We discuss these discursive contrasts in light of Bergamo's theory of ideology of health progress and Douglas' understanding of hygiene as cultural ideas. Our analysis reveals that dominant portrayals of avian influenza in the news media construct particular discourses of blame, risk, and responsibility for disease emergence and spread that are ideologically underpinned by an understanding of disease management, meat production, and animal health in Norway and Denmark as exceptional. We argue that this may have implications for perceptions of places at risk of emergence and spread of viruses and the nature of responses for pandemic preparedness and disease eradication. [ABSTRACT FROM AUTHOR]

Interactions between wildlife and livestock can lead to cross‐species disease transmission, which incurs economic costs and threatens wildlife conservation. Wild waterfowl are natural hosts of avian influenza viruses (AIVs), are often abundant near poultry farms, and have been linked to outbreaks of AIVs in poultry. Interspecific and seasonal variation in waterfowl movement and habitat use means that the risk of disease transmission between wild birds and poultry inevitably varies across species, space, and time. Here, we used GPS telemetry data from 10 waterfowl species in and near California's Central Valley, a region where both wild waterfowl and domestic poultry are abundant, to study selection of poultry farms by waterfowl across diel, seasonal, and annual cycles. We found that waterfowl selected for wetlands, open water, protected areas, and croplands, which meant that they generally avoided habitats that were likely to be used for poultry farming. These selection patterns were linked to species' ecology and diel behavioral patterns, such that avoidance of poultry habitats was stronger for local or partial migrants than for long‐distance migrants, and stronger during daytime than at night. We then combined these habitat selection results with data on poultry farm locations to map risk of waterfowl–poultry contact across the Central Valley. Average selection strength at poultry farms was low, suggesting that current placement of poultry farms is generally effective for limiting risk of contact with wild birds. When we combined these habitat selection results with data on species' abundances and AIV infection prevalence, we found dramatic variation in potential AIV transmission risk among species. These results could be used to prioritize surveillance and biosecurity efforts for regions and times of relatively high risk. More generally, these results highlight that fine‐scale movement data can help identify interspecific, seasonal, and diel patterns in animal behaviors that affect wildlife and poultry health. [ABSTRACT FROM AUTHOR]

The prevalence of highly pathogenic avian influenza (HPAI) A(H5N1) viruses has increased in wild birds and poultry worldwide, and concomitant outbreaks in mammals have occurred. During 2023, outbreaks of HPAI H5N1 virus infections were reported in cats in South Korea. The H5N1 clade 2.3.4.4b viruses isolated from 2 cats harbored mutations in the polymerase basic protein 2 gene encoding single amino acid substitutions E627K or D701N, which are associated with virus adaptation in mammals. Hence, we analyzed the pathogenicity and transmission of the cat-derived H5N1 viruses in other mammals. Both isolates caused fatal infections in mice and ferrets. We observed contact infections between ferrets, confirming the viruses had high pathogenicity and transmission in mammals. Most HPAI H5N1 virus infections in humans have occurred through direct contact with poultry or a contaminated environment. Therefore, One Health surveillance of mammals, wild birds, and poultry is needed to prevent potential zoonotic threats. [ABSTRACT FROM AUTHOR]

In July 2022, an outbreak of highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b occurred among migratory birds at Qinghai Lake in China. The virus circulated in June, and reassortants emerged after its introduction into the area. Surveillance in 2023 showed that the virus did not establish a stable presence in wild waterfowl. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza A(H5N1) virus was detected in dead seals on Tyuleniy Island in eastern Russia, in the Sea of Okhotsk. Viruses isolated from dead northern fur seals belong to clade 2.3.4.4b and are closely related to viruses detected predominantly in the Russian Far East and Japan in 2022–2023. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza (HPAI) poses a significant threat to animal and public health, with outbreaks occurring globally. HPAI poses significant challenges due to its high mortality rate and public health concerns, with outbreaks spreading globally since the emergence of the H5N1 virus in 2003. In Japan, HPAI outbreaks have been particularly prevalent during autumn and winter seasons, with the 2022-2023 winter experiencing the most severe outbreak to date. However, limited research has directly examined the association between HPAI outbreaks and weather conditions in Japan. Here we show that specific weather conditions are associated with an increased risk of HPAI outbreaks on poultry farms in Japan. By analyzing databases of HPAI cases and meteorological data from 2020-2023, we found that higher average air temperatures two to three weeks prior, lower average wind speeds four weeks prior, and longer sunlight hours two and four weeks prior to outbreaks were significantly associated with increased risk of HPAI outbreaks in Japan. These results suggest that weather may influence environmental survival and transmission of the virus, as well as patterns of wild bird movement that could seed new outbreaks. These findings enhance our understanding of the factors influencing HPAI transmission dynamics and highlight the importance of integrating weather forecasts into disease surveillance and prevention strategies. [ABSTRACT FROM AUTHOR]

Scaup, including both Lesser and Greater (Aythya affinis and Aythya marila, respectively), are a grouping of populous and widespread North American diving ducks. Few influenza type A viruses (IAV) have been reported from these species despite a high prevalence of antibodies to IAV being reported. Existing virologic and serologic data indicate that IAV infection routinely occurs in scaup, yet it is unknown which IAV subtypes are linked to these infections. In this study, we aimed to gain a more complete picture of IAV natural history in Lesser and Greater Scaup from two coastal flyways in North America in 2015-18 (302 samples from California in the Pacific Flyway and 471 samples from Maryland in the Atlantic Flyway). Low prevalence of active IAV infection was detected by real-time reverse-transcription PCR in Lesser Scaup sampled in Maryland and California (2.8% and 8.1%, respectively). A single IAV (HINI) was isolated in embryonated chicken eggs from a bird sampled in California. Similarly low levels were observed in Greater Scaup in California (3.3%). Antibodies to the nucleoprotein as detected with a commercial blocking ELISA were observed in all species and flyway combinations. Antibody seroprevalence estimates were higher in adult Lesser Scaup than in juveniles at both the <0.5 (P<0.001, z=-3.582) and <0.7 serum-sample-to-negative-control absorbance thresholds (P=0.003, z=-2.996). Neutralizing antibodies to HI-H12, H14, and H15 were detected using a microtiter virus neutralization assay, with the highest prevalence of antibodies against H1 (38%), H6 (36%), and H11 (35%). The high prevalence of antibodies to IAV and evidence of previous exposure to numerous subtypes are consistent with a high level of population immunity and a low prevalence of infection. These results must be interpreted in the context of season (winter sampling), as results may vary with the annual influx of naïve juvenile birds. [ABSTRACT FROM AUTHOR]

In poultry farming, the most important factor during their growth and production is for the birds to be free from any disease. Unmonitored and uncontrolled temperature and humidity within the cage can lead to reduced productivity and high rate of mortality. Diseases such as: avian influenza, Newcastle, fowl paralysis, semolina and so on may wipe up an entire farm in few minutes. This research used K- nearest neighbor (KNN) algorithm and developed a model to monitor such factors automatically. In the model, digital camera was deployed in the cage that records the behavior of the fowls. The model was trained on the normal behavior of a healthy/unhealthy fowl based on the clinical signs so that any abnormal sign reported immediately by the system. The experimental results show that the model can report the various diseases sign in poultry farms. [ABSTRACT FROM AUTHOR]

Introduction: Around 75% of (re)emerging infections are of zoonotic origins. The risk of zoonotic transmission in Mozambique is high because approximately 81% of the country's labor force is involved with agriculture, which represents a vulnerability for more frequent human-animal interaction and risk of spillover events. A One Health Zoonotic Disease Prioritization (OHZDP) workshop was conducted in Mozambique to facilitate coordination and collaboration within and across sectors to prevent, detect, and respond to zoonotic disease threats. Based on the success of this integrated workshop, the stakeholders developed actions whose results have a great impact on animal welfare, environment and improving public health. Methods: In 2018, representatives from Mozambique's human, animal, and environmental sectors from government, universities, research institutions and partners used US CDC's OHZDP Process to prioritize endemic and emerging zoonotic diseases of greatest national concern and develop recommendations and key interventions needed to advance One Health in Mozambique. After the OHZDP workshop, the Mozambique One Health Secretariat used a theory of change methodology to identify activities for implementation from the recommendations of the OHZDP workshop. Since the OHZDP workshop, the Secretariat has monitored progress of activities annually. Results: Mozambique's priority zoonotic diseases are rabies, zoonotic tuberculosis, salmonellosis, zoonotic avian influenza, trypanosomiasis, brucellosis, and Crimean-Congo hemorrhagic fever. One Health recommendations and interventions to address the priority zoonotic diseases focused on One Health collaboration, communication, and coordination; laboratory; surveillance; preparedness and response; prevention; workforce development; and research. After the OHZDP workshop, Mozambique established One Health coordination mechanisms, developed training courses for surveillance, laboratory diagnosis, outbreak investigation, and preparedness and response for the priority zoonotic diseases, conducted joint research, and developed plans. Conclusion: Prioritization of zoonotic diseases is critical as it facilitated the key One Health players in Mozambique to optimize resources, gain a greater understanding of zoonotic diseases, and implement policies and activities that promote multisectoral, interdisciplinary, and transdisciplinary collaboration across human, animal, and environmental sectors to prevent, detect, and respond to public health threats. The success of these activities implemented by the local Government and One Health partners were built from the implementation and momentum from the Mozambique's OHZDP workshop. [ABSTRACT FROM AUTHOR]

Simple Summary: Avian influenza (AI) is an infectious disease and could lead to death, health problems, and economic losses. Therefore, this study aimed to gather information about the compliance with and perceived effectiveness of AI control measures (applicable during high-risk periods in Flanders, North of Belgium, in 2021) by professional laying hen farmers and private bird keepers. Overall, self-reported compliance was high among professional laying hen farmers but much less among private bird keepers. Among private bird keepers, compliance and perceived effectiveness were lowest for confining the birds indoors, whereas for farmers, it was lowest for placing nets over the free-range. This study highlights the need for information campaigns explaining to private bird keepers, particularly the need for the various AI control measures imposed. Should these campaigns prove unsuccessful, local authorities might need to implement stricter enforcement of existing control measures or explore alternative ways to increase compliance, such as information posters in relevant stores for private bird keepers or meeting private bird keeper interest groups to provide broader support. Competent authorities of many countries, including Belgium, impose control measures (preventing wild bird access to feeders and water facilities, indoor confinement of captive birds, or fencing off outdoor ranges with nets) on professional and non-professional keepers of birds to prevent the spread of avian influenza (AI). Flemish laying hen farmers (FAR, n = 33) and private keepers of captive birds (PRI, n = 263) were surveyed about their opinion on and compliance with AI measures legally imposed during the most recent high-risk period before this survey in 2021. Participants answered questions on a 5-point Likert scale (1 = the worst, 3 = neutral, and 5 = the best). FAR indicated better compliance with the AI measures than PRI, except for net confinement. FAR indicated that they and other poultry farmers complied better with AI measures than PRI. Additionally, PRI indicated that they better complied than other PRI keepers. FAR regarded the AI measures as more effective than PRI. To prevent the spread of AI more effectively, national authorities could focus on information campaigns explaining to private bird keepers the need for the various control measures that they impose. If these campaigns fail, local authorities may need stricter enforcement or alternative ways to increase compliance. [ABSTRACT FROM AUTHOR]

Human-bird conflicts are in a critical state, involving economic losses such as agricultural losses, bird strikes on aircraft and avian influenza. Traditional technologies leveraging bird vision and hearing often lose their effectiveness over time as birds become habituated to these stimuli. To address these challenges, our study introduces a novel countermeasure technology based on neurophysiology. The human brain reacts to flickering light, which can cause symptoms like headaches, nausea, and dizziness. In extremely rare cases, 15 Hz flickering red light can even lead to epilepsy. Not only humans, but chickens also suffer from 14 Hz flickering light. This led us to consider the possibility that similar flickering light stimuli could be applicable to bird management. In our experiments conducted during the day, we used long-range flashlights. White flickering light had no effect on bird escape behavior. However, when cellophane film was attached to the flashlights to restrict the wavelength, the emitted red light induced escape behavior in birds. Additionally, employing two types of flashlights to generate flickering red + blue or red + green lights elicited escape behavior. However, the blue and green combination proved to be less effective. The most intense flickering frequency for crows was 15 Hz. These results are highly similar to those found in human neurophysiology, showing that red light alone and the combination of red and blue lights have the most significant impact on the brain. By measuring the flight initiation distance (FID) of birds, we found that illuminated areas had a significantly higher FID (137 m) compared to non-illuminated areas (12 m). These findings suggest that applying principles of human physiology to wildlife management can offer new solutions for bird damage control. [ABSTRACT FROM AUTHOR]

Background/Objectives: The ongoing avian influenza (H5N1) outbreak, one of the most widespread and persistent in recent history, has significantly impacted public health and the poultry and dairy cattle industries. This review covers lessons from past outbreaks, risk factors for transmission, molecular epidemiology, clinical features, surveillance strategies, and socioeconomic impacts. Since 1997, H5N1 has infected over 900 individuals globally, with a fatality rate exceeding 50%. Key factors influencing infection rates include demographic, socioeconomic, environmental, and ecological variables. The virus's potential for sustained human-to-human transmission remains a concern. The current outbreak, marked by new viral clades, has complicated containment efforts. Methods: This review discusses how to integrate technological advances, such as mathematical modeling and artificial intelligence (AI), to improve forecasting, hotspot detection, and early warning systems. Results: We provide inventories of data sources, covering both conventional and unconventional data streams, as well as those of mathematical and AI models, which can be vital for comprehensive surveillance and outbreak responses. Conclusion: In conclusion, integrating AI, mathematical models, and technological innovations into a One-Health approach is essential for improving surveillance, forecasting, and response strategies to mitigate the impacts of the ongoing avian influenza outbreak. Strengthening international collaboration and biosecurity measures will be pivotal in controlling future outbreaks and protecting both human and animal populations from this evolving global threat. [ABSTRACT FROM AUTHOR]

Knowledge and perception of poultry farmers is one of key factors to improve disease prevention practice. By collecting data from small-scale poultry farmers, this study aimed to determine the knowledge and perception of farmers towards highly pathogenic avian influenza (HPAI) prevention practice and analyse the effect of social profiles, farmer's raising behaviours on knowledge and perception of farmers. The study applied purposive sampling method to select 159 respondents in Tra Vinh Province and use multiple regression analysis to analyze data. The results showed that farmers were mostly more than 40 years old and not completed high school yet. Farmers have raised poultry under traditional methods with some feed and water from natural sources. Farmers keep cleaning and disinfect their farm frequently. The study recorded that farmer had a good knowledge and perception towards HPAI. There were some factors significantly affect the knowledge and perception of farmers including gender, training, income, poultry species, water source. Particularly, when farmers were male, joined in HPAI prevention training activities and not use water from natural source, their knowledge significantly increased. Besides, the increase in one unit of gender, income, poultry species, water source significantly increased the perception of poultry farmers. Other variables had no significant effect. It can be concluded that gender, training, income, poultry species, water source could be used to improve farmer's knowledge and perception towards HPAI prevention practice. [ABSTRACT FROM AUTHOR]

H5 subtype high-pathogenicity avian influenza (HPAI) viruses continue to devastate the poultry industry and threaten food security and public health. The first outbreak of H5 HPAI in the Philippines was reported in 2017. Since then, H5 HPAI outbreaks have been reported in 2020, 2022, and 2023. Here, we report the first publicly available complete whole-genome sequence of an H5N1 high-pathogenicity avian influenza virus from a case in Central Luzon. Samples were collected from a flock of layer chickens exhibiting signs of lethargy, droopy wings, and ecchymotic hemorrhages in trachea with excessive mucus exudates. A high mortality rate of 96–100% was observed within the week. Days prior to the high mortality event, migratory birds were observed around the chicken farm. Lungs, spleen, cloacal swabs, and oropharyngeal–tracheal swabs were taken from two chickens from this flock. These samples were positive in quantitative RT-PCR assays for influenza matrix and H5 hemagglutinin (HA) genes. To further characterize the virus, the same samples were subjected to whole-virus-genome amplification and sequencing using the Oxford Nanopore method with mean coverages of 19,190 and 2984, respectively. A phylogenetic analysis of the HA genes revealed that the H5N1 HPAI virus from Central Luzon belongs to the Goose/Guangdong lineage clade 2.3.4.4b viruses. Other segments also have high sequence identity and the same genetic lineages as other clade 2.3.4.4b viruses from Asia. Collectively, these data indicate that wild migratory birds are the likely source of H5N1 viruses from the 2022 outbreaks in the Philippines. Thus, biosecurity practices and surveillance for HPAI viruses in both domestic and wild birds should be increased to prevent and mitigate HPAI outbreaks. [ABSTRACT FROM AUTHOR]

Avian influenza (AI) and Newcastle disease (ND) are the two diseases which most threaten the health of birds and poultry. To prevent these two diseases, poultry immunization procedures have been rigorously standardized. Wild birds in Shanghai Zoo are currently immunized against both diseases with commercial vaccines for birds, but their immune status and the immune effect are not very clear. In order to determine the protective effect of the current AI (H9 subtype) and ND vaccines on wild birds in Shanghai Zoo and to explore a more reasonable and effective immunization scheme, the hemagglutination inhibition (HI) test was used to detect antibodies in some rare wild birds in the zoo six months after vaccination and to investigate the protection efficiency of the two vaccines. The results show that the H9 subtype AI immunization programs adopted by Shanghai Zoo can enable wild birds such as pheasants, waterfowl, and waders to produce antibody titers that meet national standards. The current immunization program against ND can provide sufficient protection for pheasants and waterfowl, but in some wading birds fails to reach 100% due to different species, which needs to be verified in future work. Therefore, if necessary, the vaccination interval between administration of AI vaccines (H9 subtype) can be appropriately extended to reduce the stress reaction caused by capture and vaccination and reduce the economic cost of disease prevention and control. In regard to the ND vaccine, different immunization programs should be formulated for different bird species; immunization procedures can be optimized, and the antibody level of wading birds should be monitored after vaccination. [ABSTRACT FROM AUTHOR]

Nigeria recorded one of the earliest outbreaks of the Highly Pathogenic Avian Influenza (HPAI) virus H5N1 in 2006, which spread to other African countries. In 2023, 18 countries reported outbreaks of H5N1 in poultry, with human cases documented in Egypt, Nigeria, and Djibouti. There is limited information on the molecular epidemiology of HPAI H5N1 in Nigeria. We determined the molecular epidemiology and genetic evolution of the virus from 2006 to 2021. We investigated the trend and geographical distribution across Nigeria. The evolutionary history of 61 full-length genomes was performed from 13 countries worldwide, and compared with sequences obtained from the early outbreaks in Nigeria up to 2021. MEGA 11 was used to determine the phylogenetic relationships of H5N1 strains, which revealed close ancestry between sequences in Nigeria and those from other African countries. Clade classification was performed using the subspecies classification tool for Bacterial and Viral Bioinformatics Research Center (BV-BRC) version 3.35.5. H5N1 Clade 2.2 was observed in 2006, with 2.3.2, 2.3.2.1f clades observed afterwards and 2.3.4.4b in 2021. Our findings underscore the need for genomics surveillance to track antigenic variation and clades switching to monitor the epidemiological of the virus and safeguard human and animal health. Impacts Specific variations in the hemagglutinin (HA) and neuraminidase (NA) genes of Avian influenza virus are consistent in different geographical regions. H5N1 Clade 2.2 was reported in 2006, with 2.3.2, 2.3.2.1f afterwards and 2.3.4.4b in 2021. Nigeria is an epicentre for avian influenza with three major migratory routes for wild birds transversing the country. It is plausible that the Avian influenza in Northern Nigeria may be linked to wild bird sanctuaries in the region. [ABSTRACT FROM AUTHOR]

Avian influenza viruses (AIV) are a highly contagious disease with economic and public health impact that belongs to the Orthomyxoviridae family. Wild migratory waterbirds are known as the main reservoirs of AVI which can distribute viruses to poultry and humans. Considering that Neor Lake, located in the southeast of Ardabil, is the habitat of migratory waterbirds from the countries around the region, there is a risk of transmission and distribution of influenza viruses from wild migratory birds. The present study aimed to monitor the seroprevalence of AI virus H5, H7, and H9 subtypes in migratory waterbirds of Neor Lake, Ardabil, northwest of Iran. A total of 101 blood samples were randomly collected from seven migratory bird species. HI, test was carried out on sera based on OIE protocol to detect H5, H7, and H9 subtypes. In this study, H5N2 and H7N1 antigens were used for the detection H5 and H7 subtypes, respectively. Suspicious samples on the first test were re-examined with H5N1 and H7N7 antigens. H9N2 antigen was used for the detection H9. Results of the tests performed on sera were negative for H5N1, H5N2, H7N1 and H7N7 viruses. Overall, 11.89 % of birds were seropositive for the H9N2 virus. The highest seroprevalence of the H9N2 virus was in Mallard (25 %) and the lowest seroprevalence was in Whooper swan (10.5 %). In this survey, despite seronegative evidence against H5 and H7 of subtypes, because of the prevalence of high pathogenic avian influenza (HPAI) viruses in countries of the region and some areas of Iran, it is recommended to periodically implement surveillance and control programs such as monitoring of circulating AIV in migratory waterbirds of Neor Lake. [ABSTRACT FROM AUTHOR]

Avian influenza viruses represent a significant zoonotic threat, capable of infecting a variety of avian, animal, and human species. Over recent decades, numerous human epidemic and pandemic flu outbreaks have occurred due to zoonotic avian influenza viruses worldwide. Avian influenza viruses can be transmitted from birds to humans, both directly and indirectly. Waterfowl and domestic birds serve as reservoir hosts for all subtypes of influenza viruses. Pigs and some bird species, like quail, act as mixing vessels, facilitating viral reassortment. Farmers, meat processing workers, and poultry veterinarians are at significant risk of influenza infection due to their frequent contact with ill animals and contaminated environments. As a result, using vaccines and administering efficient antiviral drugs to sick poultry are critical steps for preventing the emergence of future influenza viral pandemics. This review endeavors to furnish a comprehensive exploration of the avian influenza virus and the urgent need for proactive preventive measures. [ABSTRACT FROM AUTHOR]

Avian influenza is one of the most devastating avian diseases. The current high pathogenicity avian influenza (HPAI) A virus H5N1 clade 2.3.4.4b epizootic began in the 2020–2021 season, and has caused a panzootic, considered one of the worst ever reported. The present panzootic has novel epidemiological features that represent a challenge for its prevention and control. This review examines key epidemiological changes of the disease such as seasonality, geographic spread, and host range. The seasonality of the virus has changed, and contrary to previous avian influenza epizootics, this subclade was able to persist during boreal summer. Its geographic range has expanded, with reports in all continents except Australia. During this epizootic, HPAIV H5N1 has broadened its host range, infecting hundreds of bird species, and causing the death of thousands of wild birds and over 300 million poultry. The number and diversity of mammal species infected by H5N1 2.3.4.4b is unprecedented. Although considered low, this strain's potential to spillover to humans should not be underestimated, especially considering the current extremely high viral circulation in animals and increasing adaptation to mammals. Overall, HPAI A(H5N1) clade 2.3.4.4b represents an ongoing and growing threat to poultry, wildlife, and human health. [ABSTRACT FROM AUTHOR]

The article discusses the threat of avian influenza H5N1 to krill-dependent predators in Antarctica, specifically pinnipeds such as seals and sea lions. The virus has spread globally and can be transmitted from birds to pinnipeds with low barriers. It has caused mass die-offs in seabirds and pinnipeds in South America and has now been confirmed in several locations on the Antarctic Peninsula. The risk to Antarctic pinnipeds, such as Antarctic fur seals, is extremely high. The article recommends adopting conservation measures, enhanced surveillance and testing, and proper disposal of infected carcasses to mitigate the impact of the virus. The list of references provides additional scientific articles that discuss the detection and spread of H5N1 in marine mammals, seabirds, and pinnipeds, emphasizing the need for risk assessment and management strategies to protect wildlife populations. [Extracted from the article]

High pathogenicity avian influenza virus (HPAIV) is a rapidly evolving virus causing significant economic and environmental harm. Wild birds are a key viral reservoir and an important source of viral incursions into animal populations, including poultry. However, we lack a thorough understanding of which species drive incursions and whether this changes over time. We explored associations between the abundances of 152 avian species and outbreaks of highly pathogenic avian influenza (HPAI) in poultry premises across Great Britain between October 2021 and January 2023. Spatial generalized additive models were used, with species abundance distributions sourced from eBird. Associations were investigated at the species-specific level and across species aggregations. During autumn/winter, associations were generally strongest with waterbirds such as ducks and geese; however, we also found significant associations in groups such as non-native gamebirds and rapid change in species-specific associations over time. Our results demonstrate the value of citizen science to rapidly explore wild species as potential facilitators of disease incursions into well-monitored populations, especially in regions where viral surveillance in wild species is limited. This can be a critical step towards prioritizing targeted surveillance that could inform species-specific biosecurity measures; particularly for HPAIV, which has undergone sudden shifts in host range and continues to rapidly evolve. [ABSTRACT FROM AUTHOR]