The consequences of climate change at an avian influenza ‘hotspot’

Avian influenza viruses (AIVs) pose significant danger to human health. A key step in managing this threat is understanding the maintenance of AIVs in wild birds, their natural reservoir. Ruddy turnstones ( Arenaria interpres ) are an atypical bird species in this regard, annually experiencing high AIV prevalence in only one location—Delaware Bay, USA, during their spring migration. While there, they congregate on beaches, attracted by the super-abundance of horseshoe crab eggs. A relationship between ruddy turnstone and horseshoe crab ( Limulus polyphemus ) population sizes has been established, with a declining horseshoe crab population linked to a corresponding drop in ruddy turnstone population sizes. The effect of this interaction on AIV prevalence in ruddy turnstones has also been addressed. Here, we employ a transmission model to investigate how the interaction between these two species is likely to be altered by climate change. We explore the consequences of this modified interaction on both ruddy turnstone population size and AIV prevalence and show that, if climate change leads to a large enough mismatch in species phenology, AIV prevalence in ruddy turnstones will increase even as their population size decreases.

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Long-term Monitoring for Avian Influenza Viruses in Wild Bird Species in Italy

Veterinary Research Communications ◽

10.1023/b:verc.0000014126.72654.22 ◽

2003 ◽

Vol 27 ◽

pp. 107-114 ◽

Cited By ~ 25

Author(s):

M.A. De Marco ◽

E. Foni ◽

L. Campitelli ◽

E. Raffini ◽

M. Delogu ◽

...

Keyword(s):

Avian Influenza ◽

Wild Bird ◽

Bird Species ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Long Term Monitoring ◽

Term Monitoring

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The Impact of Migratory Flyways on the Spread of Avian Influenza Virus in North America

10.1101/074583 ◽

2016 ◽

Author(s):

Mathieu Fourment ◽

Aaron E. Darling ◽

Edward C. Holmes

Keyword(s):

Influenza Virus ◽

Genetic Structure ◽

North America ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Bird Species ◽

Influenza Viruses ◽

Data Sets ◽

Avian Influenza Viruses ◽

The Impact

AbstractWild birds are the major reservoir hosts for influenza A viruses (AIVs) and have been implicated in the emergence of pandemic events in livestock and human populations. Understanding how AIVs spread within and across continents is therefore critical to the development of successful strategies to manage and reduce the impact of influenza outbreaks. In North America many bird species undergo seasonal migratory movements along a North-South axis, thereby fostering opportunities for viruses to spread over long distances. However, the role played by such avian flyways in shaping the genetic structure of AIV populations has proven controversial. To assess the relative contribution of bird migration along flyways to the genetic structure of AIV we performed a large-scale phylogeographic study of viruses sampled in the USA and Canada, involving the analysis of 3805 to 4505 sequences from 36 to 38 geographic localities depending on the gene data set. To assist this we developed a maximum likelihood-based genetic algorithm to explore a wide range of complex spatial models, thereby depicting a more complete picture of the migration network than previous studies. Based on phylogenies estimated from nucleotide data sets, our results show that AIV migration rates within flyways are significantly higher than those between flyways, indicating that the migratory patterns of birds play a key role in pathogen dispersal. These findings provide valuable insights into the evolution, maintenance and transmission of AIVs, in turn allowing the development of improved programs for surveillance and risk assessment.Significance StatementAvian influenza viruses infect a wide variety of wild bird species and represent a potential disease threat to the poultry industry and hence to human and livestock populations. However, the ecological factors that drive the geographic spread and evolution of these viruses are both poorly understood and controversial at the continental scale, particularly the role played by migratory flyways in shaping patterns of virus dispersal. Using a novel phylogeographic analysis of large genomic data sets we show migration flyways act as important transmission barriers to the spread of avian influenza viruses in North America. Hence, these results indicate that the spread of avian influenza virus in wild birds in North America has an element of predictability.

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Attachment Patterns of Human and Avian Influenza Viruses to Trachea and Colon of 26 Bird Species – Support for the Community Concept

Frontiers in Microbiology ◽

10.3389/fmicb.2019.00815 ◽

2019 ◽

Vol 10 ◽

Cited By ~ 4

Author(s):

Per Eriksson ◽

Cecilia Lindskog ◽

Victor Lorente-Leal ◽

Jonas Waldenström ◽

Daniel González-Acuna ◽

...

Keyword(s):

Avian Influenza ◽

Bird Species ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Attachment Patterns ◽

Community Concept

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Variation in viral shedding patterns between different wild bird species infected experimentally with low-pathogenicity avian influenza viruses that originated from wild birds

Avian Pathology ◽

10.1080/03079457.2010.540002 ◽

2011 ◽

Vol 40 (2) ◽

pp. 119-124 ◽

Cited By ~ 53

Author(s):

Taiana P. Costa ◽

Justin D. Brown ◽

Elizabeth W. Howerth ◽

David E. Stallknecht

Keyword(s):

Avian Influenza ◽

Wild Bird ◽

Bird Species ◽

Wild Birds ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Viral Shedding

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Biological Properties and Genetic Characterization of Novel Low Pathogenic H7N3 Avian Influenza Viruses Isolated from Mallard Ducks in the Caspian Region, Dagestan, Russia

Microorganisms ◽

10.3390/microorganisms9040864 ◽

2021 ◽

Vol 9 (4) ◽

pp. 864

Author(s):

Marina Gulyaeva ◽

Maria Alessandra De Marco ◽

Ganna Kovalenko ◽

Eric Bortz ◽

Tatiana Murashkina ◽

...

Keyword(s):

Avian Influenza ◽

Caspian Sea ◽

Wild Bird ◽

Bird Species ◽

Biological Properties ◽

Influenza Viruses ◽

Caspian Region ◽

Avian Influenza Viruses ◽

The Caspian Sea ◽

Bird Migrations

Avian influenza viruses (AIVs) are maintained in wild bird reservoirs, particularly in mallard ducks and other waterfowl. Novel evolutionary lineages of AIV that arise through genetic drift or reassortment can spread with wild bird migrations to new regions, infect a wide variety of resident bird species, and spillover to domestic poultry. The vast continental reservoir of AIVs in Eurasia harbors a wide diversity of influenza subtypes, including both highly pathogenic (HP) and low pathogenic (LP) H7 AIV. The Caspian Sea region is positioned at the intersection of major migratory flyways connecting Central Asia, Europe, the Black and Mediterranean Sea regions and Africa and holds a rich wetland and avian ecology. To understand genetic reservoirs present in the Caspian Sea region, we collected 559 cloacal swabs from Anseriformes and other species during the annual autumn migration periods in 2017 and 2018. We isolated two novel H7N3 LPAIV from mallard ducks whose H7 hemagglutinin (HA) gene was phylogenetically related to contemporaneous strains from distant Mongolia, and more closely Georgia and Ukraine, and predated the spread of this H7 LPAIV sublineage into East Asia in 2019. The N3 neuraminidase gene and internal genes were prototypical of AIV widely dispersed in wild bird reservoirs sampled along flyways connected to the Caspian region. The polymerase and nucleoprotein segments clustered with contemporaneous H5 HPAI (clade 2.3.4.4b) isolates, suggesting the wide dispersal of H7 LPAIV and the potential of this subtype for reassortment. These findings highlight the need for deeper surveillance of AIV in wild birds to better understand the extent of infection spread and evolution along spatial and temporal flyways in Eurasia.

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Pathogenicity of three genetically distinct and highly pathogenic Egyptian H5N8 avian influenza viruses in chickens

10.21203/rs.3.rs-372409/v1 ◽

2021 ◽

Author(s):

Nahed Yehia ◽

Ahmed M Erfan ◽

amany adel ◽

marwa abdelmagid ◽

Wafaa M M Hassan ◽

...

Keyword(s):

Avian Influenza ◽

Bird Species ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Highly Pathogenic ◽

Predominant Genotype ◽

Multiple Introductions ◽

Pathological Alteration ◽

Hpai H5n1 ◽

The Difference

Abstract In late 2016, Egypt was subjected to multiple introductions of reassorted highly pathogenic avian influenza viruses (HPAI) subtype H5N8. In a previous study, we reported three distinct genotypes during the first wave of infection represented by CAO285, SS19, and F446 viruses that were isolated from wild birds, backyard, and a commercial farm, respectively. F466 has subsequently become the predominant genotype currently circulating in Egypt and has been implicated in the emerging of the H5N2 virus. In the present study, we investigated the difference in the pathogenicity and transmissibility of the three genotypes. The intravenous pathogenicity index (IVPI) ranged from 2.68 to 2.9. With the natural route of infection, all these strains took longer to cause mortality in comparison to S75 (HPAI-H5N1). When compared the H5N8 viruses to each other showed that F446 had high mortality rate after inoculation from original concentration of 106 and 104 EID50 of virus. Chickens inoculated with F446 showed the highest viral titer with significant differnt in all tested samples (H5N8 and H5N1 viruses) in experimental and sentinel contact chicken with more efficient transmission to sentinel contact birds and spread from contact to other birds. Histopathological findings revealed the H5N1 and H5N8 viruses affect all organs examined (lung, trachea, brain, spleen) with relatively different affect the S75 cauterized by early marked respiratory adverse effect and F446 & SS19 were characterized by early systematic pathological alteration with mild respiratory pathological changes. The efficient viral replication and transmissibility in the main bird species, like chicken in case of Egypt, represent a key element for the spread and maintains of certain influenza genotypes of H5N8 virus and decrease the incidence of H5N1.

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