| 1. |
- Mahmoud, Sara H., et al.
(författare)
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Immunogenicity and Cross-Protective Efficacy Induced by an Inactivated Recombinant Avian Influenza A/H5N1 (Clade 2.3.4.4b) Vaccine against Co-Circulating Influenza A/H5Nx Viruses
- 2023
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Ingår i: Vaccines. - : MDPI. - 2076-393X. ; 11:9
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Tidskriftsartikel (refereegranskat)abstract
- Controlling avian influenza viruses (AIVs) is mainly based on culling of the infected bird flocks or via the implementation of inactivated vaccines in countries where AIVs are considered to be endemic. Over the last decade, several avian influenza virus subtypes, including highly pathogenic avian influenza (HPAI) H5N1 clade 2.2.1.2, H5N8 clade 2.3.4.4b and the recent H5N1 clade 2.3.4.4b, have been reported among poultry populations in Egypt. This demanded the utilization of a nationwide routine vaccination program in the poultry sector. Antigenic differences between available avian influenza vaccines and the currently circulating H5Nx strains were reported, calling for an updated vaccine for homogenous strains. In this study, three H5Nx vaccines were generated by utilizing the reverse genetic system: rgH5N1_2.3.4.4, rgH5N8_2.3.4.4 and rgH5N1_2.2.1.2. Further, the immunogenicity and the cross-reactivity of the generated inactivated vaccines were assessed in the chicken model against a panel of homologous and heterologous H5Nx HPAIVs. Interestingly, the rgH5N1_2.3.4.4 induced high immunogenicity in specific-pathogen-free (SPF) chicken and could efficiently protect immunized chickens against challenge infection with HPAIV H5N1_2.3.4.4, H5N8_2.3.4.4 and H5N1_2.2.1.2. In parallel, the rgH5N1_2.2.1.2 could partially protect SPF chickens against infection with HPAIV H5N1_2.3.4.4 and H5N8_2.3.4.4. Conversely, the raised antibodies to rgH5N1_2.3.4.4 could provide full protection against HPAIV H5N1_2.3.4.4 and HPAIV H5N8_2.3.4.4, and partial protection (60%) against HPAIV H5N1_2.2.1.2. Compared to rgH5N8_2.3.4.4 and rgH5N1_2.2.1.2 vaccines, chickens vaccinated with rgH5N1_2.3.4.4 showed lower viral shedding following challenge infection with the predefined HPAIVs. These data emphasize the superior immunogenicity and cross-protective efficacy of the rgH5N1_2.3.4.4 in comparison to rgH5N8_2.3.4.4 and rgH5N1_2.2.1.2.
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| 2. |
- Abdel-Moneim, Ahmed S., et al.
(författare)
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WSV 2019 : The First Committee Meeting of the World Society for Virology
- 2020
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Ingår i: Virologica Sinica. - : Elsevier BV. - 1674-0769 .- 1995-820X. ; 35:2, s. 248-252
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The World Society for Virology (WSV) was founded and incorporated as a nonprofit organization in the United States in 2017. WSV seeks to strengthen and support both virological research and virologists who conduct research of viruses that affect humans, other animals, plants, and other organisms. One of the objectives of WSV is to connect virologists worldwide and support collaboration. Fulfilling this objective, virologists from fourteen countries in North America, Europe, Africa, Asia, and the Middle East met on 25-27th August 2019 in Stockholm, Sweden at the Karolinska University Hospital for the first Committee Meeting of WSV. This meeting included compelling keynote and honorary speeches and a series of 18 scientific talks were given encompassing a diverse array of subjects within virology. Followed by the scientific session, a business session was held where multiple aspects and next steps of the society were discussed and charted out.
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| 3. |
- Abozeid, Hassanein H., et al.
(författare)
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Infectious Bronchitis Virus in Egypt : Genetic Diversity and Vaccination Strategies
- 2020
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Ingår i: Veterinary Sciences. - : MDPI. - 2306-7381. ; 7:4
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Forskningsöversikt (refereegranskat)abstract
- Infectious bronchitis virus (IBV) is a highly evolving avian pathogen that has increasingly imposed a negative impact on poultry industry worldwide. In the last 20 years, IBV has been continuously circulating among chicken flocks in Egypt causing huge economic losses to poultry production. Multiple IBV genotypes, namely, GI-1, GI-13, GI-16, and GI-23 have been reported in Egypt possessing different genetic and pathogenic features. Different vaccine programs are being used to control the spread of the disease in Egypt. However, the virus continues to spread and evolve where multiple IBV variants and several recombination evidence have been described. In this review, we highlight the current knowledge concerning IBV circulation, genesis, and vaccination strategies in Egypt. In addition, we analyze representative Egyptian IBV strains from an evolutionary perspective based on available data of their S1 gene. We also provide insight into the importance of surveillance programs and share our perspectives for better control of IBV circulating in Egypt.
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| 4. |
- Adel, Amany, et al.
(författare)
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Genetic Variations among Different Variants of G1-like Avian Influenza H9N2 Viruses and Their Pathogenicity in Chickens
- 2022
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Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 14:5
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Tidskriftsartikel (refereegranskat)abstract
- Since it was first discovered, the low pathogenic avian influenza (LPAI) H9N2 subtype has established linages infecting the poultry population globally and has become one of the most prevalent influenza subtypes in domestic poultry. Several different variants and genotypes of LPAI H9N2 viruses have been reported in Egypt, but little is known about their pathogenicity and how they have evolved. In this study, four different Egyptian LPAI H9N2 viruses were genetically and antigenically characterized and compared to representative H9N2 viruses from G1 lineage. Furthermore, the pathogenicity of three genetically distinct Egyptian LPAI H9N2 viruses was assessed by experimental infection in chickens. Whole-genome sequencing revealed that the H9N2 virus of the Egy-2 G1-B lineage (pigeon-like) has become the dominant circulating H9N2 genotype in Egypt since 2016. Considerable variation in virus shedding at day 7 post-infections was detected in infected chickens, but no significant difference in pathogenicity was found between the infected groups. The rapid spread and emergence of new genotypes of the influenza viruses pinpoint the importance of continuous surveillance for the detection of novel reassortant viruses, as well as monitoring the viral evolution.
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| 5. |
- Amer, Fatma, et al.
(författare)
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Temporal Dynamics of Influenza A(H5N1) Subtype before and after the Emergence of H5N8
- 2021
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Ingår i: Viruses. - : MDPI. - 1999-4915. ; 13:8
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Tidskriftsartikel (refereegranskat)abstract
- Highly pathogenic avian influenza (HPAI) viruses continue to circulate worldwide, causing numerous outbreaks among bird species and severe public health concerns. H5N1 and H5N8 are the two most fundamental HPAI subtypes detected in birds in the last two decades. The two viruses may compete with each other while sharing the same host population and, thus, suppress the spread of one of the viruses. In this study, we performed a statistical analysis to investigate the temporal correlation of the HPAI H5N1 and HPAI H5N8 subtypes using globally reported data in 2015-2020. This was joined with an in-depth analysis using data generated via our national surveillance program in Egypt. A total of 6412 outbreaks were reported worldwide during this period, with 39% (2529) as H5N1 and 61% (3883) as H5N8. In Egypt, 65% of positive cases were found in backyards, while only 12% were found in farms and 23% in live bird markets. Overall, our findings depict a trade-off between the number of positive H5N1 and H5N8 samples around early 2017, which is suggestive of the potential replacement between the two subtypes. Further research is still required to elucidate the underpinning mechanisms of this competitive dynamic. This, in turn, will implicate the design of effective strategies for disease control.
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| 6. |
- Erfan, Ahmed M., et al.
(författare)
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Characterization of full genome sequences of chicken anemia viruses circulating in Egypt reveals distinct genetic diversity and evidence of recombination
- 2018
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Ingår i: Virus Research. - : ELSEVIER SCIENCE BV. - 0168-1702 .- 1872-7492. ; 251, s. 78-85
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Tidskriftsartikel (refereegranskat)abstract
- Chicken anemia virus (CAV) is one of the commercially important diseases of poultry worldwide. In Egypt, CAV has been reported to be a potential threat to the commercial poultry sectors. Hence, this study was aimed at isolation and full genomic analysis of CAVs circulating in chicken populations in different geographical location in Egypt. A total of 42 samples were collected from broiler chicken flocks in 9 governorates in Egypt from 12 to 42 days of age. The mortality rate observed among chickens was ranging from 3% to 22%. Nineteen out of 42 farms were found positive for the CAV genome by polymerase chain reaction (PCR). Full genome sequencing was conducted for 18 positive samples. Genetic analysis revealed a high similarity of > 99% in 11 viruses with the vaccine strain Del-Ros; while the other seven samples shared close similarity to CAV field strains isolated from China, Taiwan, and Brazil. The data also indicated Q139 and Q144 amino acids substitutions among the VP1 of Egyptian field strains, which are known to be important in virus replication and spread. Phylogenetic analysis of the sequenced viruses (n = 18) based on either the full gene nucleotide sequence or VP1 coding sequence, suggested the circulation of four distinct genotypes in Egypt designated as group A, B, C and D. Moreover, evidence of recombination was detected among four Egyptian CAVs located within group A. The findings of this study succeeded to elucidate the epidemiological and genetic features of CAVs circulating in Egypt, and underscores the important of CAVs surveillance.
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| 7. |
- Erfan, Ahmed M., et al.
(författare)
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Chicken anaemia virus enhances and prolongs subsequent avian influenza (H9N2) and infectious bronchitis viral infections
- 2019
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Ingår i: Veterinary Microbiology. - : ELSEVIER SCIENCE BV. - 0378-1135 .- 1873-2542. ; 230, s. 123-129
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Tidskriftsartikel (refereegranskat)abstract
- Immunosuppressive viral diseases have a great economic importance in the poultry industry due to the increased susceptibility to secondary infections. Chicken anaemia virus (CAV) is one of the major immunosuppressive diseases in chickens. In addition, low pathogenic avian influenza (LPAI) of subtype H9N2 and infectious bronchitis (IB) viruses are among the most frequently reported respiratory viral diseases in poultry worldwide. In the present study, specific pathogen free chickens were used to understand the impact of CAV on secondary infection with LPAI-H9N2 or 1B viruses. Clinical outcomes, viral shedding dynamics, and cytokine levels wereassessed. The results exhibit that chickens previously infected with CAV produceconsiderablyhigher titresof LPAI-H9N2 or IB viruses in the oropharyngeal swabs (P < 0.05), tracheas and kidneys. In addition, the immunologic effect of CAV provokedthe development of clinical signs of LPAI-H9N2 and IB virus infections. Moreover, results suggested that pre-infection with CAV directly correlated with elevated levels of IL-6 and IFN gamma. These findings underline the importance of CAV pre-infection on LPAI-H9N2 or IB infection in chickens, and indicate that co-circulation of CAV can contribute to the spread and evolution of LPAI H9N2 and IB viruses.
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| 8. |
- Hagag, Naglaa M., et al.
(författare)
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Isolation of a Novel Reassortant Highly Pathogenic Avian Influenza (H5N2) Virus in Egypt
- 2019
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Ingår i: Viruses. - : MDPI. - 1999-4915. ; 11:6
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Tidskriftsartikel (refereegranskat)abstract
- Highly pathogenic avian influenza (HPAI) H5N1 and H5N8 have become endemic among domestic poultry in Egypt since 2006 and 2016, respectively. In parallel, the low pathogenic avian influenza H9N2 virus has been endemic since 2010. Despite the continuous circulation of these subtypes for several years, no natural reassortant has been detected so far among the domestic poultry population in Egypt. In this study, the HPAI (H5N2) virus was isolated from a commercial duck farm, giving evidence of the emergence of the first natural reassortment event in domestic poultry in Egypt. The virus was derived as a result of genetic reassortment between avian influenza viruses of H5N8 and H9N2 subtypes circulating in Egypt. The exchange of the neuraminidase segment and high number of acquired mutations might be associated with an alteration in the biological propensities of this virus.
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| 9. |
- Hagag, Naglaa M., et al.
(författare)
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Molecular Epidemiology and Evolutionary Analysis of Avian Influenza A(H5) Viruses Circulating in Egypt, 2019-2021
- 2022
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Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 14:8
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Tidskriftsartikel (refereegranskat)abstract
- The highly pathogenic avian influenza (HPAI) H5N8 virus was first detected in Egypt in late 2016. Since then, the virus has spread rapidly among different poultry sectors, becoming the dominant HPAI H5 subtype reported in Egypt. Different genotypes of the HPAI H5N8 virus were reported in Egypt; however, the geographic patterns and molecular evolution of the Egyptian HPAI H5N8 viruses are still unclear. Here, extensive epidemiological surveillance was conducted, including more than half a million samples collected from different poultry sectors (farms/backyards/live bird markets) from all governorates in Egypt during 2019-2021. In addition, genetic characterization and evolutionary analyses were performed using 47 selected positive H5N8 isolates obtained during the same period. The result of the conducted surveillance showed that HPAI H5N8 viruses of clade 2.3.4.4b continue to circulate in different locations in Egypt, with an obvious seasonal pattern, and no further detection of the HPAI H5N1 virus of clade 2.2.1.2 was observed in the poultry population during 2019-2021. In addition, phylogenetic and Bayesian analyses revealed that two major genotypes (G5 and G6) of HPAI H5N8 viruses were continually expanding among the poultry sectors in Egypt. Notably, molecular dating analysis suggested that the Egyptian HPAI H5N8 virus is the potential ancestral viruses of the European H5N8 viruses of 2020-2021. In summary, the data of this study highlight the current epidemiology, diversity, and evolution of HPAI H5N8 viruses in Egypt and call for continuous monitoring of the genetic features of the avian influenza viruses in Egypt.
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| 10. |
- Li, Ruiyun, et al.
(författare)
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Phylogeographic Dynamics of Influenza A(H9N2) Virus Crossing Egypt
- 2020
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Ingår i: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Low pathogenic avian influenza (LPAI) virus of subtype H9N2 is the most frequently detected subtype among domestic poultry and is a public health concern because of its zoonotic potential. Due to the multiple and complex routes of LPAIV H9N2 between geographic regions, little is known about the spatial diffusion of H9N2 virus to, within, and from Egypt, where it is endemic among poultry since 2011. Using close to 800 publicly available hemagglutinin (HA) segment nucleotide sequences, associated location and temporal data, we conducted a Bayesian discrete phylogeographic analysis. Here, we reconstructed and traced the origin, spread and principal transmission routes of H9N2 across large geographical regions, in addition to the transmission between Egypt and the rest of the world and between different Egyptian governorates. Our analysis suggests that during the last few decades, H9N2 has been introduced back and forth continuously between the countries where it is endemic. Amongst these regions, Saudi Arabia, United Arab Emirates and Iraq act as main distribution hubs and drive the viral migration worldwide, with bi-directional and long-distance diffusions. It is noteworthy that H9N2 was introduced once to Egypt via Israel in mid 2009, and that the descendants of the Egyptian LAIVs H9N2 were back-transmitted to Israel in 2015. Additionally, governorates in middle Egypt (Giza, Fayoum and Bani Souwaif) are major hubs in the LPAIV H9N2 transmission network in Egypt. This knowledge highlights that H9N2 is both a global and a national concern and can aid in updating the surveillance program and vaccine strain selection.
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