Survey of low pathogenic avian influenza viruses in live poultry markets in Guangxi Province, Southern China, 2016–2019

AbstractLow pathogenic avian influenza viruses (LPAIVs) have been widespread in poultry and wild birds throughout the world for many decades. LPAIV infections are usually asymptomatic or cause subclinical symptoms. However, the genetic reassortment of LPAIVs may generate novel viruses with increased virulence and cross-species transmission, posing potential risks to public health. To evaluate the epidemic potential and infection landscape of LPAIVs in Guangxi Province, China, we collected and analyzed throat and cloacal swab samples from chickens, ducks and geese from the live poultry markets on a regular basis from 2016 to 2019. Among the 7,567 samples, 974 (12.87%) were LPAIVs-positive, with 890 single and 84 mixed infections. Higher yearly isolation rates were observed in 2017 and 2018. Additionally, geese had the highest isolation rate, followed by ducks and chickens. Seasonally, spring had the highest isolation rate. Subtype H3, H4, H6 and H9 viruses were detected over prolonged periods, while H1 and H11 viruses were detected transiently. The predominant subtypes in chickens, ducks and geese were H9, H3, and H6, respectively. The 84 mixed infection samples contained 22 combinations. Most mixed infections involved two subtypes, with H3 + H4 as the most common combination. Our study provides important epidemiological data regarding the isolation rates, distributions of prevalent subtypes and mixed infections of LPAIVs. These results will improve our knowledge and ability to control epidemics, guide disease management strategies and provide early awareness of newly emerged AIV reassortants with pandemic potential.

Download Full-text

Surveillance of Live Poultry Markets for Low Pathogenic Avian Influenza Viruses in Guangxi Province, Southern China, from 2012–2015

Scientific Reports ◽

10.1038/s41598-017-17740-0 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 12

Author(s):

Sisi Luo ◽

Zhixun Xie ◽

Zhiqin Xie ◽

Liji Xie ◽

Li Huang ◽

...

Keyword(s):

Avian Influenza ◽

Southern China ◽

Influenza Viruses ◽

Guangxi Province ◽

Avian Influenza Viruses ◽

Pathogenic Avian Influenza ◽

Live Poultry ◽

Low Pathogenic Avian Influenza ◽

Live Poultry Markets

Download Full-text

Continued Evolution of H5Nx Avian Influenza Viruses in Bangladeshi Live Poultry Markets: Pathogenic Potential in Poultry and Mammalian Models

Journal of Virology ◽

10.1128/jvi.01141-20 ◽

2020 ◽

Vol 94 (23) ◽

Author(s):

Rabeh El-Shesheny ◽

John Franks ◽

Jasmine Turner ◽

Patrick Seiler ◽

David Walker ◽

...

Keyword(s):

Avian Influenza ◽

Active Surveillance ◽

Highly Pathogenic Avian Influenza ◽

Influenza Viruses ◽

Limited Capacity ◽

Avian Influenza Viruses ◽

Highly Pathogenic ◽

Pathogenic Avian Influenza ◽

Live Poultry ◽

Live Poultry Markets

ABSTRACT The genesis of novel influenza viruses through reassortment poses a continuing risk to public health. This is of particular concern in Bangladesh, where highly pathogenic avian influenza viruses of the A(H5N1) subtype are endemic and cocirculate with other influenza viruses. Active surveillance of avian influenza viruses in Bangladeshi live poultry markets detected three A(H5) genotypes, designated H5N1-R1, H5N1-R2, and H5N2-R3, that arose from reassortment of A(H5N1) clade 2.3.2.1a viruses. The H5N1-R1 and H5N1-R2 viruses contained HA, NA, and M genes from the A(H5N1) clade 2.3.2.1a viruses and PB2, PB1, PA, NP, and NS genes from other Eurasian influenza viruses. H5N2-R3 viruses contained the HA gene from circulating A(H5N1) clade 2.3.2.1a viruses, NA and M genes from concurrently circulating A(H9N2) influenza viruses, and PB2, PB1, PA, NP, and NS genes from other Eurasian influenza viruses. Representative viruses of all three genotypes and a parental clade 2.3.2.1a strain (H5N1-R0) infected and replicated in mice without prior adaptation; the H5N2-R3 virus replicated to the highest titers in the lung. All viruses efficiently infected and killed chickens. All viruses replicated in inoculated ferrets, but no airborne transmission was detected, and only H5N2-R3 showed limited direct-contact transmission. Our findings demonstrate that although the A(H5N1) viruses circulating in Bangladesh have the capacity to infect and replicate in mammals, they show very limited capacity for transmission. However, reassortment does generate viruses of distinct phenotypes. IMPORTANCE Highly pathogenic avian influenza A(H5N1) viruses have circulated continuously in Bangladesh since 2007, and active surveillance has detected viral evolution driven by mutation and reassortment. Recently, three genetically distinct A(H5N1) reassortant viruses were detected in live poultry markets in Bangladesh. Currently, we cannot assign pandemic risk by only sequencing viruses; it must be conducted empirically. We found that the H5Nx highly pathogenic avian influenza viruses exhibited high virulence in mice and chickens, and one virus had limited capacity to transmit between ferrets, a property considered consistent with a higher zoonotic risk.

Download Full-text

Detection of low pathogenic avian influenza viruses in wild birds in Castilla-La Mancha (south central Spain)

Veterinary Microbiology ◽

10.1016/j.vetmic.2010.05.008 ◽

2010 ◽

Vol 146 (3-4) ◽

pp. 200-208 ◽

Cited By ~ 29

Author(s):

Elisa Pérez-Ramírez ◽

Xeider Gerrikagoitia ◽

Marta Barral ◽

Ursula Höfle

Keyword(s):

Avian Influenza ◽

Wild Birds ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Central Spain ◽

Pathogenic Avian Influenza ◽

South Central ◽

La Mancha ◽

Low Pathogenic Avian Influenza

Download Full-text

Ecology of H3 avian influenza viruses in Korea and assessment of their pathogenic potentials

Journal of General Virology ◽

10.1099/vir.0.83462-0 ◽

2008 ◽

Vol 89 (4) ◽

pp. 949-957 ◽

Cited By ~ 34

Author(s):

Min-Suk Song ◽

Taek-Kyu Oh ◽

Ho Jin Moon ◽

Dai-Woon Yoo ◽

Eun Ho Lee ◽

...

Keyword(s):

Avian Influenza ◽

Wild Bird ◽

Migratory Birds ◽

Influenza Viruses ◽

Interspecies Transmission ◽

Avian Influenza Viruses ◽

Backyard Poultry ◽

Live Poultry ◽

Live Poultry Markets

To determine the genetic origins of novel H3 avian influenza viruses of chickens and ducks in Korea, genetic characterization of H3 avian influenza viruses isolated from live poultry markets and migratory aquatic birds in South Korea during 2004–2006 was conducted. Phylogenetic analysis revealed that at least four novel genotypes of H3N2 and two genotypes of H3N6 avian influenza viruses were co-circulating in backyard poultry of Korea. The viruses were reassortants between H9N2 viruses of Korean chickens and unknown influenza viruses of migratory birds. Genetic comparison of H3 viruses from live bird markets with those from wild bird isolates revealed that certain gene segments of wild bird isolates are related closely to those of Korean group H9N2 viruses isolated from live poultry markets in 2003. Furthermore, animal-challenge studies demonstrated that the pathogenicity of certain avian H3 influenza viruses was altered due to reassortment, leading to H3 avian influenza viruses in Korea that can potentially expand their host range to include mammals. These studies emphasize the continuing need to monitor backyard poultry at live poultry markets to better understand interspecies transmission and the emergence of novel influenza viruses that have the potential to infect humans.

Download Full-text

Detection of Low Pathogenic Avian Influenza Viruses in Wild Ducks from Canada: Comparison of Two Sampling Methods

Journal of Wildlife Diseases ◽

10.7589/0090-3558-47.2.466 ◽

2011 ◽

Vol 47 (2) ◽

pp. 466-470 ◽

Cited By ~ 8

Author(s):

E. Jane Parmley ◽

Catherine Soos ◽

André Breault ◽

Madeleine Fortin ◽

Emily Jenkins ◽

...

Keyword(s):

Avian Influenza ◽

Sampling Methods ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Pathogenic Avian Influenza ◽

Low Pathogenic Avian Influenza

Download Full-text

Opposite outcomes of the within-host competition between highly and low pathogenic H5N8 avian influenza viruses in chickens compared to ducks

Journal of Virology ◽

10.1128/jvi.01366-21 ◽

2021 ◽

Author(s):

Pierre Bessière ◽

Thomas Figueroa ◽

Amelia Coggon ◽

Charlotte Foret-Lucas ◽

Alexandre Houffschmitt ◽

...

Keyword(s):

Avian Influenza ◽

Reverse Genetics ◽

Highly Pathogenic Avian Influenza ◽

Viral Evolution ◽

Influenza Viruses ◽

Poultry Production ◽

Avian Influenza Viruses ◽

Highly Pathogenic ◽

Pathogenic Avian Influenza ◽

Low Pathogenic Avian Influenza

Highly pathogenic avian influenza viruses (HPAIV) emerge from low pathogenic avian influenza viruses (LPAIV) through the introduction of basic amino acids at the hemagglutinin (HA) cleavage site. Following viral evolution, the newly formed HPAIV likely represents a minority variant within the index host, predominantly infected with the LPAIV precursor. Using reverse-genetics engineered H5N8 viruses differing solely at the HA cleavage, we tested the hypothesis that the interaction between the minority HPAIV and the majority LPAIV could modulate the risk of HPAIV emergence and that the nature of the interaction could depend on the host species. In chickens, we observed that the H5N8 LP increased H5N8 HP replication and pathogenesis. By contrast, the H5N8 LP antagonized H5N8 HP replication and pathogenesis in ducks. Ducks mounted a more potent antiviral innate immune response than chickens against the H5N8 LP , which correlated with H5N8 HP inhibition. These data provide experimental evidence that HPAIV may be more likely to emerge in chickens than in ducks and underscore the importance of within-host viral variants interactions in viral evolution. IMPORTANCE Highly pathogenic avian influenza viruses represent a threat to poultry production systems and to human health because of their impact on food security and because of their zoonotic potential. It is therefore crucial to better understand how these viruses emerge. Using a within-host competition model between highly and low pathogenic avian influenza viruses, we provide evidence that highly pathogenic avian influenza viruses could be more likely to emerge in chickens than in ducks. These results have important implications for highly pathogenic avian influenza virus emergence prevention and they underscore the importance of within-host viral variants interactions in virus evolution.

Download Full-text