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Tang Z, Carrel M, Koylu C, Kitchen A. How human ecology landscapes shape the circulation of H5N1 avian influenza: A case study in Indonesia. One Health 2023. [DOI: 10.1016/j.onehlt.2023.100537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
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2
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Pan X, Su X, Ding P, Zhao J, Cui H, Yan D, Teng Q, Li X, Beerens N, Zhang H, Liu Q, de Jong MCM, Li Z. Maternal-derived antibodies hinder the antibody response to H9N2 AIV inactivated vaccine in the field. ANIMAL DISEASES 2022. [DOI: 10.1186/s44149-022-00040-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractThe H9N2 subtype avian influenza virus (AIV) inactivated vaccine has been used extensively in poultry farms, but it often fails to stimulate a sufficiently high immune response in poultry in the field, although it works well in laboratory experiments; hence, the virus still causes economic damage every year and poses a potential threat to public health. Based on surveillance data collected in the field, we found that broilers with high levels of maternal-derived antibodies (MDAs) against H9N2 virus did not produce high levels of antibodies after vaccination with a commercial H9N2 inactivated vaccine. In contrast, specific pathogen-free (SPF) chickens without MDAs responded efficiently to that vaccination. When MDAs were mimicked by administering passively transferred antibodies (PTAs) into SPF chickens in the laboratory, similar results were observed: H9N2-specific PTAs inhibited humoral immunity against the H9N2 inactivated vaccine, suggesting that H9N2-specific MDAs might hinder the generation of antibodies when H9N2 inactivated vaccine was used. After challenge with homologous H9N2 virus, the virus was detected in oropharyngeal swabs of the vaccinated and unvaccinated chickens with PTAs but not in the vaccinated chickens without PTAs, indicating that H9N2-specific MDAs were indeed one of the reasons for H9N2 inactivated vaccine failure in the field. When different titers of PTAs were used to mimic MDAs in SPF chickens, high (HI = 12 log2) and medium (HI = log 9 log2) titers of PTAs reduced the generation of H9N2-specific antibodies after the first vaccination, but a booster dose would induce a high and faster humoral immune response even of PTA interference. This study strongly suggested that high or medium titers of MDAs might explain H9N2 inactivated vaccine failure in the field.
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3
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Shurson GC, Urriola PE, van de Ligt JLG. Can we effectively manage parasites, prions, and pathogens in the global feed industry to achieve One Health? Transbound Emerg Dis 2021; 69:4-30. [PMID: 34171167 DOI: 10.1111/tbed.14205] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/14/2021] [Accepted: 06/22/2021] [Indexed: 11/30/2022]
Abstract
Prions and certain endoparasites, bacteria, and viruses are internationally recognized as types of disease-causing biological agents that can be transmitted from contaminated feed to animals. Historically, foodborne biological hazards such as prions (transmissible spongiform encephalopathy), endoparasites (Trichinella spiralis, Toxoplasma gondii), and pathogenic bacteria (Salmonella spp., Listeria monocytogenes, Escherichia coli O157, Clostridium spp., and Campylobacter spp.) were major food safety concerns from feeding uncooked or improperly heated animal-derived food waste and by-products. However, implementation of validated thermal processing conditions along with verifiable quality control procedures has been effective in enabling safe use of these feed materials in animal diets. More recently, the occurrence of global Porcine Epidemic Diarrhea Virus and African Swine Fever Virus epidemics, dependence on international feed ingredient supply chains, and the discovery that these viruses can survive in some feed ingredient matrices under environmental conditions of trans-oceanic shipments has created an urgent need to develop and implement rigorous biosecurity protocols that prevent and control animal viruses in feed ingredients. Implementation of verifiable risk-based preventive controls, traceability systems from origin to destination, and effective mitigation procedures is essential to minimize these food security, safety, and sustainability threats. Creating a new biosafety and biosecurity framework will enable convergence of the diverging One Health components involving low environmental impact and functional feed ingredients that are perceived as having elevated biosafety risks when used in animal feeds.
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Affiliation(s)
- Gerald C Shurson
- Department of Animal Science, College of Food Agricultural and Natural Resource Sciences, University of Minnesota, St. Paul, Minnesota, USA
| | - Pedro E Urriola
- Department of Animal Science, College of Food Agricultural and Natural Resource Sciences, University of Minnesota, St. Paul, Minnesota, USA
| | - Jennifer L G van de Ligt
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA
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4
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Adel A, Mosaad Z, Shalaby AG, Selim K, Samy M, Abdelmagid MA, Hagag NM, Arafa AS, Hassan WM, Shahien MA. Molecular evolution of the hemagglutinin gene and epidemiological insight into low-pathogenic avian influenza H9N2 viruses in Egypt. Res Vet Sci 2021; 136:540-549. [PMID: 33887563 DOI: 10.1016/j.rvsc.2021.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 03/19/2021] [Accepted: 04/12/2021] [Indexed: 10/21/2022]
Abstract
Despite the low pathogenicity of the H9N2 avian influenza viruses, they can induce severe economic losses in various poultry sectors in conjunction with other factors. In Egypt, low-pathogenic avian influenza (LPAI) H9N2 became endemic in 2011 and has undergone continuous genetic evolution since then. The regular monitoring of the evolution of the virus is necessary to control its spread. During 2017-2020, there were 44 positive samples isolated, and these viruses were genetically sequenced to determine the hemagglutinin (HA) gene circulating in Egypt. The molecular analysis revealed at least nine changes in amino acid residues in comparison with the reference Egyptian strain from the original introduction in 2011 (A/qu/Egypt/113413v/2011), with a similarity of 95%-96%. Amino acid residues 180 and 216 are the most important residues in terms of positive selection pressure. Phylogenetically, the new Egyptian H9N2 viruses in 2017-2020 belonged to a new subcluster related to the strains that had been circulating since 2015. Comparative analysis of the HA gene of LPAI H9N2 viruses in Egypt from 2011 to 2020 supports a continuous evolution through the years with persistent markers.
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Affiliation(s)
- Amany Adel
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt.
| | - Zienab Mosaad
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Azhar G Shalaby
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Karim Selim
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Mohamed Samy
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Marwa A Abdelmagid
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Naglaa M Hagag
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Abdel Satar Arafa
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Wafaa M Hassan
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
| | - Momtaz A Shahien
- Reference Laboratory for Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt
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5
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Ayala AJ, Yabsley MJ, Hernandez SM. A Review of Pathogen Transmission at the Backyard Chicken-Wild Bird Interface. Front Vet Sci 2020; 7:539925. [PMID: 33195512 PMCID: PMC7541960 DOI: 10.3389/fvets.2020.539925] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 08/13/2020] [Indexed: 01/31/2023] Open
Abstract
Habitat conversion and the expansion of domesticated, invasive species into native habitats are increasingly recognized as drivers of pathogen emergence at the agricultural-wildlife interface. Poultry agriculture is one of the largest subsets of this interface, and pathogen spillover events between backyard chickens and wild birds are becoming more commonly reported. Native wild bird species are under numerous anthropogenic pressures, but the risks of pathogen spillover from domestic chickens have been historically underappreciated as a threat to wild birds. Now that the backyard chicken industry is one of the fastest growing industries in the world, it is imperative that the principles of biosecurity, specifically bioexclusion and biocontainment, are legislated and implemented. We reviewed the literature on spillover events of pathogens historically associated with poultry into wild birds. We also reviewed the reasons for biosecurity failures in backyard flocks that lead to those spillover events and provide recommendations for current and future backyard flock owners.
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Affiliation(s)
- Andrea J. Ayala
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Michael J. Yabsley
- Daniel B. Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, United States
- Southeastern Cooperative Wildlife Disease Study, Athens, GA, United States
| | - Sonia M. Hernandez
- Daniel B. Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, United States
- Southeastern Cooperative Wildlife Disease Study, Athens, GA, United States
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6
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Karo-Karo D, Pribadi ES, Sudirman FX, Kurniasih SW, Indasari I, Muljono DH, Koch G, Stegeman JA. Highly Pathogenic Avian Influenza A(H5N1) Outbreaks in West Java Indonesia 2015-2016: Clinical Manifestation and Associated Risk Factors. Microorganisms 2019; 7:E327. [PMID: 31500141 PMCID: PMC6788193 DOI: 10.3390/microorganisms7090327] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 08/20/2019] [Accepted: 09/05/2019] [Indexed: 01/13/2023] Open
Abstract
Knowledge of outbreaks and associated risk factors is helpful to improve control of the Highly Pathogenic Avian Influenza A(H5N1) virus (HPAI) in Indonesia. This study was conducted to detect outbreaks of HPAI H5N1 in endemically infected regions by enhanced passive surveillance, to describe the clinical manifestation of these outbreaks and identify associated risk factors. From November 2015 to November 2016, HPAI outbreak investigations were conducted in seven districts of West Java. In total 64 outbreaks were confirmed out of 75 reported suspicions and outbreak characteristics were recorded. The highest mortality was reported in backyard chickens (average 59%, CI95%: 49-69%). Dermal apoptosis and lesions (64%, CI95%: 52-76%) and respiratory signs (39%, CI95%: 27-51%) were the clinical signs observed overall most frequently, while neurological signs were most frequently observed in ducks (68%, CI95%: 47-90%). In comparison with 60 non-infected control farms, the rate of visitor contacts onto a farm was associated with the odds of HPAI infection. Moreover, duck farms had higher odds of being infected than backyard farms, and larger farms had lower odds than small farms. Results indicate that better external biosecurity is needed to reduce transmission of HPAI A(H5N1) in Indonesia.
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Affiliation(s)
- Desniwaty Karo-Karo
- Department of Farm Animal Health, Faculty of Veterinary Medicine Utrecht University, 3584 CL Utrecht, The Netherlands
- Centre for Diagnostic Standard of Indonesian Agricultural Quarantine Agency, Ministry of Agriculture, Jakarta 13220, Indonesia
| | - Eko Sugeng Pribadi
- Center for Tropical Animal Studies, Institute of Research and Community Empowerment, Bogor Agricultural University, Bogor 16129, Indonesia
| | | | | | - Iin Indasari
- West Java Province Animal Health Agency, Bandung 40135, Indonesia
| | | | - Guus Koch
- Wageningen Bioveterinary Research, 8221 RA Lelystad, The Netherlands
| | - Jan Arend Stegeman
- Department of Farm Animal Health, Faculty of Veterinary Medicine Utrecht University, 3584 CL Utrecht, The Netherlands.
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7
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Awada L, Tizzani P, Noh SM, Ducrot C, Ntsama F, Caceres P, Mapitse N, Chalvet-Monfray K. Global dynamics of highly pathogenic avian influenza outbreaks in poultry between 2005 and 2016-Focus on distance and rate of spread. Transbound Emerg Dis 2018; 65:2006-2016. [PMID: 30079591 DOI: 10.1111/tbed.12986] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 07/23/2018] [Accepted: 07/25/2018] [Indexed: 01/05/2023]
Abstract
Highly pathogenic avian influenza (HPAI) is of major importance for human and animal health because of high morbidity and mortality in poultry and the potential for transmission of this zoonotic pathogen to humans. Knowledge of HPAI epidemiology in avian populations and practical information on the temporal and spatial spread of the disease after introduction into a country is important in order to enhance the capacity of predicting and managing epidemics to minimize the negative impacts on human and animal health. Using data reported to the World Organisation for Animal Health between 2005 and 2017 by 199 countries for 14,129 outbreaks in poultry, we used a spatial and time-series analysis to determine that: (a) During the last 12 years, there were two major global peaks in the number of countries affected by HPAI with 23% and 26% of countries affected in 2006 and 2016. (b) Based on the seasonality analysis, spread is the lowest in September, begins to rise in October, and peaks in February. (c) The median distance HPAI outbreaks spread from the index outbreak was 111 km, while the median apparent rate of spread of outbreaks was 1.9 km/day. (d) In 39% of HPAI events, the disease did not spread beyond the index outbreak and the median maximum spread from the index outbreak per event was 45 km. (e) The distance HPAI outbreaks spread from the index outbreak was significantly negatively correlated with the number of outbreaks during the same time period, indicating that the spread of HPAI was lower during global panzootics than during periods of low transmission. These findings are of major importance for veterinary services to design and implement surveillance measures for improving preparedness to minimize the impacts of this disease.
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Affiliation(s)
- Lina Awada
- World Animal Health Information and Analysis Department, World Organisation for Animal Health, Paris, France.,UMR EPIA, INRA VetAgro Sup, Marcy l'Etoile, France
| | - Paolo Tizzani
- World Animal Health Information and Analysis Department, World Organisation for Animal Health, Paris, France
| | - Susan Marite Noh
- World Animal Health Information and Analysis Department, World Organisation for Animal Health, Paris, France.,Animal Disease Research Unit, USDA-Agricultural Research Service, Pullman, Washington
| | | | - Francois Ntsama
- World Animal Health Information and Analysis Department, World Organisation for Animal Health, Paris, France
| | - Paula Caceres
- World Animal Health Information and Analysis Department, World Organisation for Animal Health, Paris, France
| | - Neo Mapitse
- World Animal Health Information and Analysis Department, World Organisation for Animal Health, Paris, France
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8
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Kim HK, Jeong DG, Yoon SW. Recent outbreaks of highly pathogenic avian influenza viruses in South Korea. Clin Exp Vaccine Res 2017; 6:95-103. [PMID: 28775973 PMCID: PMC5540969 DOI: 10.7774/cevr.2017.6.2.95] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 06/07/2017] [Accepted: 06/11/2017] [Indexed: 01/13/2023] Open
Abstract
Outbreaks of H5 highly pathogenic avian influenza viruses (HPAIVs) have caused economic loss for the poultry industry and posed a threat to public health. In South Korea, novel reassortants of HPAIVs such as H5N6 and H5N8 had been circulating in poultry. Here, we will discuss the identity of recent novel reassortants of Korean H5 HPAIVs and the recent advances in vaccine development, which will be useful for controlling HPAIV transmission in poultry and for effectively preventing future epidemics and pandemics.
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Affiliation(s)
- Hye Kwon Kim
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
| | - Dae Gwin Jeong
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea.,University of Science and Technology (UST), Daejeon, Korea
| | - Sun-Woo Yoon
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea.,University of Science and Technology (UST), Daejeon, Korea
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9
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Peeters B, Reemers S, Dortmans J, de Vries E, de Jong M, van de Zande S, Rottier PJM, de Haan CAM. Genetic versus antigenic differences among highly pathogenic H5N1 avian influenza A viruses: Consequences for vaccine strain selection. Virology 2017; 503:83-93. [PMID: 28135661 DOI: 10.1016/j.virol.2017.01.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/16/2017] [Accepted: 01/19/2017] [Indexed: 01/03/2023]
Abstract
Highly pathogenic H5N1 avian influenza A viruses display a remarkable genetic and antigenic diversity. We examined to what extent genetic distances between several H5N1 viruses from different clades correlate with antigenic differences and vaccine performance. H5-specific antisera were generated, and cross-reactivity and antigenic distances between 12 different viruses were determined. In general, antigenic distances increased proportional to genetic distances although notable exceptions were observed. Antigenic distances correlated better with genetic variation in 27 selected, antigenically-relevant H5 residues, than in the complete HA1 domain. Variation in these selected residues could accurately predict the antigenic distances for a novel H5N8 virus. Protection provided by vaccines against heterologous H5N1 challenge viruses indicated that cross-protection also correlates better with genetic variation in the selected antigenically-relevant residues than in complete HA1. When time is limited, variation at these selected residues may be used to accurately predict antigenic distance and vaccine performance.
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Affiliation(s)
- Ben Peeters
- Department of Virology, Wageningen Bioveterinary Research, Lelystad, The Netherlands.
| | | | - Jos Dortmans
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands
| | - Erik de Vries
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands
| | - Mart de Jong
- Department of Quantitative Veterinary Epidemiology, Wageningen University, Wageningen, The Netherlands
| | | | - Peter J M Rottier
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands
| | - Cornelis A M de Haan
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht, The Netherlands.
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10
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Sitaras I, Rousou X, Peeters B, de Jong MC. Mutations in the haemagglutinin protein and their effect in transmission of highly pathogenic avian influenza (HPAI) H5N1 virus in sub-optimally vaccinated chickens. Vaccine 2016; 34:5512-5518. [DOI: 10.1016/j.vaccine.2016.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 09/29/2016] [Accepted: 10/03/2016] [Indexed: 10/20/2022]
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11
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Sitaras I, Rousou X, Kalthoff D, Beer M, Peeters B, de Jong MCM. Role of vaccination-induced immunity and antigenic distance in the transmission dynamics of highly pathogenic avian influenza H5N1. J R Soc Interface 2016; 13:20150976. [PMID: 26763336 DOI: 10.1098/rsif.2015.0976] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Highly pathogenic avian influenza (HPAI) H5N1 epidemics in poultry cause huge economic losses as well as sporadic human morbidity and mortality. Vaccination in poultry has often been reported as being ineffective in preventing transmission and as a potential driving force in the selection of immune escape mutants. We conducted transmission experiments to evaluate the transmission dynamics of HPAI H5N1 strains in chickens vaccinated with high and low doses of immune escape mutants we have previously selected, and analysed the data using mathematical models. Remarkably, we demonstrate that the effect of antigenic distances between the vaccine and challenge strains used in this study is too small to influence the transmission dynamics of the strains used. This is because the effect of a sufficient vaccine dose on antibody levels against the challenge viruses is large enough to compensate for any decrease in antibody titres due to antigenic differences between vaccine and challenge strains. Our results show that at least under experimental conditions, vaccination will remain effective even after antigenic changes as may be caused by the initial selection in vaccinated birds.
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Affiliation(s)
- Ioannis Sitaras
- Quantitative Veterinary Epidemiology, Department of Animal Sciences, Wageningen University, Radix Building 107, Droevendaalsesteeg 1, Wageningen 6708 PB, The Netherlands Department of Virology, Central Veterinary Institute of Wageningen University and Research Centre, Houtribweg 39, Lelystad 8221 RA, The Netherlands
| | - Xanthoula Rousou
- Quantitative Veterinary Epidemiology, Department of Animal Sciences, Wageningen University, Radix Building 107, Droevendaalsesteeg 1, Wageningen 6708 PB, The Netherlands
| | - Donata Kalthoff
- Institute of Diagnostic Virology, Friedrich-Löffler Institut, Südufer 10, Greifswald-Insel Riems 17493, Germany
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Löffler Institut, Südufer 10, Greifswald-Insel Riems 17493, Germany
| | - Ben Peeters
- Department of Virology, Central Veterinary Institute of Wageningen University and Research Centre, Houtribweg 39, Lelystad 8221 RA, The Netherlands
| | - Mart C M de Jong
- Quantitative Veterinary Epidemiology, Department of Animal Sciences, Wageningen University, Radix Building 107, Droevendaalsesteeg 1, Wageningen 6708 PB, The Netherlands
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12
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Aptamers in diagnostics and treatment of viral infections. Viruses 2015; 7:751-80. [PMID: 25690797 PMCID: PMC4353915 DOI: 10.3390/v7020751] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 01/13/2015] [Accepted: 02/12/2015] [Indexed: 02/07/2023] Open
Abstract
Aptamers are in vitro selected DNA or RNA molecules that are capable of binding a wide range of nucleic and non-nucleic acid molecules with high affinity and specificity. They have been conducted through the process known as SELEX (Systematic Evolution of Ligands by Exponential Enrichment). It serves to reach specificity and considerable affinity to target molecules, including those of viral origin, both proteins and nucleic acids. Properties of aptamers allow detecting virus infected cells or viruses themselves and make them competitive to monoclonal antibodies. Specific aptamers can be used to interfere in each stage of the viral replication cycle and also inhibit its penetration into cells. Many current studies have reported possible application of aptamers as a treatment or diagnostic tool in viral infections, e.g., HIV (Human Immunodeficiency Virus), HBV (Hepatitis B Virus), HCV (Hepatitis C Virus), SARS (Severe Acute Respiratory Syndrome), H5N1 avian influenza and recently spread Ebola. This review presents current developments of using aptamers in the diagnostics and treatment of viral diseases.
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13
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Antibody response and risk factors for seropositivity in backyard poultry following mass vaccination against highly pathogenic avian influenza and Newcastle disease in Indonesia. Epidemiol Infect 2014; 143:1632-42. [PMID: 25316261 DOI: 10.1017/s0950268814002623] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A large-scale mass vaccination campaign was carried out in Java, Indonesia in an attempt to control outbreaks of highly pathogenic avian influenza (HPAI) in backyard flocks and commercial smallholder poultry. Sero-monitoring was conducted in mass vaccination and control areas to assess the proportion of the target population with antibodies against HPAI and Newcastle disease (ND). There were four rounds of vaccination, and samples were collected after each round resulting in a total of 27 293 samples. Sampling was performed irrespective of vaccination status. In the mass vaccination areas, 20-45% of poultry sampled had a positive titre to H5 after each round of vaccination, compared to 2-3% in the control group. In the HPAI + ND vaccination group, 12-25% of the population had positive ND titres, compared to 5-13% in the areas without ND vaccination. The level of seropositivity varied by district, age of the bird, and species (ducks vs. chickens).
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14
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Abdelwhab EM, Veits J, Mettenleiter TC. Prevalence and control of H7 avian influenza viruses in birds and humans. Epidemiol Infect 2014; 142:896-920. [PMID: 24423384 PMCID: PMC9151109 DOI: 10.1017/s0950268813003324] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 11/21/2013] [Accepted: 12/04/2013] [Indexed: 01/20/2023] Open
Abstract
The H7 subtype HA gene has been found in combination with all nine NA subtype genes. Most exhibit low pathogenicity and only rarely high pathogenicity in poultry (and humans). During the past few years infections of poultry and humans with H7 subtypes have increased markedly. This review summarizes the emergence of avian influenza virus H7 subtypes in birds and humans, and the possibilities of its control in poultry. All H7Nx combinations were reported from wild birds, the natural reservoir of the virus. Geographically, the most prevalent subtype is H7N7, which is endemic in wild birds in Europe and was frequently reported in domestic poultry, whereas subtype H7N3 is mostly isolated from the Americas. In humans, mild to fatal infections were caused by subtypes H7N2, H7N3, H7N7 and H7N9. While infections of humans have been associated mostly with exposure to domestic poultry, infections of poultry have been linked to wild birds or live-bird markets. Generally, depopulation of infected poultry was the main control tool; however, inactivated vaccines were also used. In contrast to recent cases caused by subtype H7N9, human infections were usually self-limiting and rarely required antiviral medication. Close genetic and antigenic relatedness of H7 viruses of different origins may be helpful in development of universal vaccines and diagnostics for both animals and humans. Due to the wide spread of H7 viruses and their zoonotic importance more research is required to better understand the epidemiology, pathobiology and virulence determinants of these viruses and to develop improved control tools.
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Affiliation(s)
- E M Abdelwhab
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Molecular Biology, Greifswald - Insel Riems, Germany
| | - J Veits
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Molecular Biology, Greifswald - Insel Riems, Germany
| | - T C Mettenleiter
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Molecular Biology, Greifswald - Insel Riems, Germany
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15
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Pantin-Jackwood MJ, Suarez DL. Vaccination of domestic ducks against H5N1 HPAI: A review. Virus Res 2013; 178:21-34. [DOI: 10.1016/j.virusres.2013.07.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 05/21/2013] [Accepted: 07/18/2013] [Indexed: 01/08/2023]
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16
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Wiwanitkit V, Shi B, Xia S, Yang GJ, Zhou XN, Liu J. Research priorities in modeling the transmission risks of H7N9 bird flu. Infect Dis Poverty 2013; 2:17. [PMID: 23927386 PMCID: PMC3751567 DOI: 10.1186/2049-9957-2-17] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 08/06/2013] [Indexed: 11/10/2022] Open
Abstract
The epidemic of H7N9 bird flu in eastern China in early 2013 has caused much attention from researchers as well as public health workers. The issue on modeling the transmission risks is very interesting topic. In this article, this issue is debated and discussed in order to promote further researches on prediction and prevention of avian influenza viruses supported by better interdisciplinary datasets from the surveillance and response system.
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