scholarly journals Novel reassortant of H9N2 avian influenza viruses isolated from chickens and quails in Egypt

2021 ◽  
pp. 2142-2149
Author(s):  
Moataz Elsayed ◽  
AbdelSatar Arafa ◽  
Shahira Abdelwahab ◽  
Amro Hashish ◽  
Ahmed Youssef
Keyword(s):  
Avian Influenza ◽  
Influenza Pandemic ◽  
Phylogenetic Analyses ◽  
Influenza Viruses ◽  
H9n2 Virus ◽  
Avian Influenza Viruses ◽  
Genetic Changes ◽  
Genome Variability ◽  
Commercial Chicken ◽  
Amino Acid Mutations

Background and Aim: Poultry infections with H9N2 avian influenza viruses (AIVs) are endemic in Egypt. This study determined the genetic changes in the sequences of H9N2 AIVs isolated from chicken and quails in Egypt, including determining genetic reassortment and detecting the main genetic changes in hemagglutinin (HA) and neuraminidase (NA) genes. Materials and Methods: Swab samples were collected from chicken and quails, examined through reverse transcription-polymerase chain reaction, and AIVs from positive samples were isolated in embryonated chicken eggs. Complete genome sequencing and phylogenetic analyses were conducted for two H9N2 AIV isolates, and sequences of HA and NA gene segments were analyzed in another two isolates. Results: A novel reassortant virus was identified from a commercial chicken flock (A/chicken/Egypt/374V/2016) and quails from a live bird market (A/quail/Egypt/1253V/2016). The reassortant viruses acquired four genome segments from the classic Egyptian H9N2 viruses (HA, NA, NP, and M) and four segments from Eurasian AIVs (PB2, PB1, PA, and NS). Many genetic changes have been demonstrated in HA and NA genes. The isolated novel reassortant H9N2 virus from quails showed amino acid mutations in the antigenic sites on the globular head of the mature HA monomer matched with the parent Egyptian H9N2 virus. Conclusion: This work described the genetic characterization of a novel reassortment of the H9N2 virus in Egypt. The emergence of new reassorted AIV viruses and genome variability raises the concern of an influenza pandemic with zoonotic potentials.

scholarly journals Lessons From Influenza Pandemics of the Last 100 Years

2019 ◽  
Author(s):  
Arnold S Monto ◽  
Keiji Fukuda
Keyword(s):  
Avian Influenza ◽  
Seasonal Influenza ◽  
Influenza Pandemic ◽  
Risk Groups ◽  
Influenza Viruses ◽  
Avian Influenza Viruses ◽  
Influenza Pandemics ◽  
Fundamental Difficulty ◽  
1918 Influenza ◽  
The Impact

Abstract Seasonal influenza is an annual occurrence, but it is the threat of pandemics that produces universal concern. Recurring reports of avian influenza viruses severely affecting humans have served as constant reminders of the potential for another pandemic. Review of features of the 1918 influenza pandemic and subsequent ones helps in identifying areas where attention in planning is critical. Key among such issues are likely risk groups and which interventions to employ. Past pandemics have repeatedly underscored, for example, the vulnerability of groups such as pregnant women and taught other lessons valuable for future preparedness. While a fundamental difficulty in planning for the next pandemic remains their unpredictability and infrequency, this uncertainty can be mitigated, in part, by optimizing the handling of the much more predictable occurrence of seasonal influenza. Improvements in antivirals and novel vaccine formulations are critical in lessening the impact of both pandemic and seasonal influenza.

scholarly journals Contribution of Segment 3 to the Acquisition of Virulence in Contemporary H9N2 Avian Influenza Viruses

2020 ◽  
Vol 94 (20) ◽  
Author(s):  
Anabel L. Clements ◽  
Joshua E. Sealy ◽  
Thomas P. Peacock ◽  
Jean-Remy Sadeyen ◽  
Saira Hussain ◽  
...  
Keyword(s):  
Middle East ◽  
Avian Influenza ◽  
Mortality Rates ◽  
Influenza Viruses ◽  
H9n2 Virus ◽  
Morbidity And Mortality ◽  
Single Amino Acid ◽  
Economic Damage ◽  
Poultry Production ◽  
Avian Influenza Viruses

ABSTRACT H9N2 avian influenza viruses (AIVs) circulate in poultry throughout much of Asia, the Middle East, and Africa. These viruses cause huge economic damage to poultry production systems and pose a zoonotic threat both in their own right and in the generation of novel zoonotic viruses, for example, H7N9. In recent years, it has been observed that H9N2 viruses have further adapted to gallinaceous poultry, becoming more highly transmissible and causing higher morbidity and mortality. Here, we investigate the molecular basis for this increased virulence, comparing a virus from the 1990s and a contemporary field strain. The modern virus replicated to higher titers in various systems, and this difference mapped to a single amino acid polymorphism at position 26 of the endonuclease domain shared by the PA and PA-X proteins. This change was responsible for increased replication and higher morbidity and mortality rates along with extended tissue tropism seen in chickens. Although the PA K26E change correlated with increased host cell shutoff activity of the PA-X protein in vitro, it could not be overridden by frameshift site mutations that block PA-X expression and therefore increased PA-X activity could not explain the differences in replication phenotype. Instead, this indicates that these differences are due to subtle effects on PA function. This work gives insight into the ongoing evolution and poultry adaptation of H9N2 and other avian influenza viruses and helps us understand the striking morbidity and mortality rates in the field, as well as the rapidly expanding geographical range seen in these viruses. IMPORTANCE Avian influenza viruses, such as H9N2, cause huge economic damage to poultry production worldwide and are additionally considered potential pandemic threats. Understanding how these viruses evolve in their natural hosts is key to effective control strategies. In the Middle East and South Asia, an older H9N2 virus strain has been replaced by a new reassortant strain with greater fitness. Here, we take representative viruses and investigate the genetic basis for this “fitness.” A single mutation in the virus was responsible for greater fitness, enabling high growth of the contemporary H9N2 virus in cells, as well as in chickens. The genetic mutation that modulates this change is within the viral PA protein, a part of the virus polymerase gene that contributes to viral replication as well as to virus accessory functions—however, we find that the fitness effect is specifically due to changes in the protein polymerase activity.

scholarly journals The PB2 and M genes of genotype S H9N2 virus contribute to the enhanced fitness of H5Nx and H7N9 avian influenza viruses in chickens

Virology ◽  
2019 ◽  
Vol 535 ◽  
pp. 218-226 ◽  
Author(s):  
Xiaoli Hao ◽  
Xiaoquan Wang ◽  
Jiao Hu ◽  
Min Gu ◽  
Jiongjiong Wang ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Influenza Viruses ◽  
H9n2 Virus ◽  
Avian Influenza Viruses

scholarly journals Pathobiology of the highly pathogenic avian influenza viruses H7N1 and H5N8 in different chicken breeds and role of Mx 2032 G/A polymorphism in infection outcome

2020 ◽  
Vol 51 (1) ◽  
Author(s):  
Raúl Sánchez-González ◽  
Antonio Ramis ◽  
Miquel Nofrarías ◽  
Nabil Wali ◽  
Rosa Valle ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Highly Pathogenic Avian Influenza ◽  
Oral Route ◽  
Influenza Viruses ◽  
Avian Influenza Viruses ◽  
Highly Pathogenic ◽  
Viral Shedding ◽  
Pathogenic Avian Influenza ◽  
Commercial Chicken ◽  
Chicken Breeds

Abstract Chickens are highly susceptible to highly pathogenic avian influenza viruses (HPAIVs). However, the severity of infection varies depending of the viral strain and the genetic background of the host. In this study, we evaluated the pathogenesis of two HPAIVs (H7N1 and H5N8) and assessed the susceptibility to the infection of local and commercial chicken breeds from Spain. Eight chicken breeds were intranasally inoculated with 105 ELD50 of A/Chicken/Italy/5093/1999 (H7N1) or A/Goose/Spain/IA17CR02699/2017 (H5N8 clade 2.3.4.4. B) and monitored during 10 days. Chickens were highly susceptible to both HPAIVs, but H7N1 was considerably more virulent than H5N8 as demonstrated by the highest mortality rates and shortest mean death times (MDT). Both HPAIVs produced severe necrosis and intense viral replication in the central nervous system, heart and pancreas; however, the lesions and replication in other tissues were virus-dependent. High levels of viral RNA were detected by the oral route with both viruses. In contrast, a low number of H5N8-inoculated chickens shed by the cloacal route, demonstrating a different pattern of viral shedding dependent of the HPAIV. We found a high variation in the susceptibility to HPAIVs between the different chicken breeds. The birds carrying the genotype AA and AG at position 2032 in chicken Mx gene presented a slightly higher, but not significant, percentage of survival and a statistically significant longer MDT than GG individuals. Our study demonstrated that the severity of HPAI infection is largely dependent of the viral isolate and host factors, underlining the complexity of HPAI infections.

scholarly journals Continuous Reassortment of Clade 2.3.4.4 H5N6 Highly Pathogenetic Avian Influenza Viruses Demonstrating High Risk to Public Health

Pathogens ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 670 ◽  
Author(s):  
Huanan Li ◽  
Qian Li ◽  
Bo Li ◽  
Yang Guo ◽  
Jinchao Xing ◽  
...  
Keyword(s):  
Public Health ◽  
High Risk ◽  
Avian Influenza ◽  
Migratory Birds ◽  
Influenza Pandemic ◽  
Influenza Viruses ◽  
Avian Influenza Viruses ◽  
The World

Since it firstly emerged in China in 2013, clade 2.3.4.4 H5N6 highly pathogenic avian influenza viruses (HPAIVs) has rapidly replaced predominant H5N1 to become the dominant H5 subtype in China, especially in ducks. Not only endemic in China, it also crossed the geographical barrier and emerged in South Korea, Japan, and Europe. Here, we analyzed the genetic properties of the clade 2.3.4.4 H5N6 HPAIVs with full genome sequences available online together with our own isolates. Phylogenetic analysis showed that clade 2.3.4.4 H5N6 HPAIVs continuously reassorted with local H5, H6, and H7N9/H9N2. Species analysis reveals that aquatic poultry and migratory birds became the dominant hosts of H5N6. Adaption to aquatic poultry might help clade 2.3.4.4 H5N6 better adapt to migratory birds, thus enabling it to become endemic in China. Besides, migratory birds might help clade 2.3.4.4 H5N6 transmit all over the world. Clade 2.3.4.4 H5N6 HPAIVs also showed a preference for α2,6-SA receptors when compared to other avian origin influenza viruses. Experiments in vitro and in vivo revealed that clade 2.3.4.4 H5N6 HPAIVs exhibited high replication efficiency in both avian and mammal cells, and it also showed high pathogenicity in both mice and chickens, demonstrating high risk to public health. Considering all the factors together, adaption to aquatic poultry and migratory birds helps clade 2.3.4.4 H5N6 overcome the geographical isolation, and it has potential to be the next influenza pandemic in the world, making it worthy of our attention.

scholarly journals Scoring Amino Acid Mutations to Predict Avian-to-Human Transmission of Avian Influenza Viruses

Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1584 ◽  
Author(s):  
Xiaoli Qiang ◽  
Zheng Kou ◽  
Gang Fang ◽  
Yanfeng Wang
Keyword(s):  
Amino Acid ◽  
Avian Influenza ◽  
Influenza Viruses ◽  
Avian Influenza Viruses ◽  
Amino Acid Mutations

scholarly journals Mouse-adapted H9N2 avian influenza virus causes systemic infection in mice

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Zhe Hu ◽  
Yiran Zhang ◽  
Zhen Wang ◽  
Jingjing Wang ◽  
Qi Tong ◽  
...  
Keyword(s):  
Amino Acid ◽  
Avian Influenza ◽  
Genomic Sequence ◽  
Systemic Infection ◽  
Influenza Viruses ◽  
Avian Influenza Viruses ◽  
Host Switch ◽  
H9n2 Avian Influenza Virus ◽  
Amino Acid Mutations ◽  
Adaptation Ability

Abstract Background H9N2 influenza viruses continuously circulate in multiple avian species and are repeatedly transmitted to humans, posing a significant threat to public health. To investigate the adaptation ability of H9N2 avian influenza viruses (AIVs) to mammals and the mutations related to the host switch events, we serially passaged in mice two H9N2 viruses of different HA lineages — A/Quail/Hong Kong/G1/97 (G1) of the G1-like lineage and A/chicken/Shandong/ZB/2007 (ZB) of the BJ/94-like lineage —and generated two mouse-adapted H9N2 viruses (G1-MA and ZB-MA) that possessed significantly higher virulence than the wide-type viruses. Finding ZB-MA replicated systemically in mice. Genomic sequence alignment revealed 10 amino acid mutations coded by 4 different gene segments (PB2, PA, HA, and M) in G1-MA compared with the G1 virus and 23 amino acid mutations in 5 gene segments (PB1, PA, HA, M, and NS) in ZB-MA compared to ZB virus, indicating that the mutations in the polymerase, HA, M, and NS genes play critical roles in the adaptation of H9N2 AIVs to mammals, especially, the mutations of M1-Q198H and M1-A239T were shared in G1-MA and ZB-MA viruses. Additionally, several substitutions showed a higher frequency in human influenza viruses compared with avian viruses. Conclusions Different lineages of H9N2 could adapt well in mice and some viruses could gain the ability to replicate systemically and become neurovirulent. Thus, it is essential to pay attention to the mammalian adaptive evolution of the H9N2 virus.

scholarly journals Bioaerosol Sampling at a Live Animal Market in Kunshan, China: A Noninvasive Approach for Detecting Emergent Viruses

2020 ◽  
Vol 7 (5) ◽  
Author(s):  
Xinye Wang ◽  
Emily S Bailey ◽  
Xian Qi ◽  
Huiyan Yu ◽  
Changjun Bao ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Influenza Viruses ◽  
H9n2 Virus ◽  
Molecular Evidence ◽  
Avian Influenza Viruses ◽  
Live Animal ◽  
Live Bird Market ◽  
Live Bird

From October to December 2018, periodic bioaerosol sampling was conducted at a live bird market in Kunshan, China. Sixty-six (55%) of 120 samples had molecular evidence of avian influenza viruses. Four yielded live H9N2 virus after egg culture.

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