Conventional and future diagnostics for avian influenza

https://doi.org/10.1016/j.cimid.2008.01.009Get rights and content

Abstract

The significant and continued transboundary spread of Asian avian influenza H5N1 since 2003, paired with documented transmission from avian species to humans and other mammals, has focused global attention on avian influenza virus detection and diagnostic strategies. While the historic and conventional laboratory methods used for isolation and identification of the virus and for detection of specific antibodies continued to be widely applied, new and emerging technologies are rapidly being adapted to support avian influenza virus surveillance and diagnosis worldwide. Molecular tools in particular are advancing toward lab-on-chip and fully integrated technologies that are capable of same day detection, pathotyping, and phylogenetic characterization of influenza A viruses obtained from clinical specimens. The future of avian influenza diagnostics, rather than moving toward a single approach, is wisely adopting a strategy that takes advantage of the range of conventional and advancing technologies to be used in “fit-for-purpose” testing.

Résumé

La propagation significative et continue de la souche asiatique de la grippe aviaire H5N1 par delà les frontières depuis 2003, combinée à la transmission avérée des oiseaux aux humains et autres mammifères, a focalisé l’attention générale sur les stratégies de diagnostic et de détection du virus de la grippe aviaire. À côté des méthodes conventionnelles et historiques utilisées par les laboratoires pour isoler et identifier les virus, ainsi que détecter des anticorps spécifiques, de nouvelles technologies sont rapidement adaptées au contrôle et au diagnostic de la grippe aviaire dans le monde entier. Les outils moléculaires, en particulier, permettent d’améliorer les technologies de laboratoire sur puce parfaitement intégrées permettant la détection, la détermination du pathotype et la caractérisation phylogénétique de virus influenza de type A issus de spécimens cliniques. Plutôt que d’opter pour une approche unique, la tendance en matière de diagnostic de la grippe aviaire est plutôt à l’adoption d’une stratégie qui exploite les différentes technologies conventionnelles et avancées afin de réaliser des tests « sur mesure ».

Introduction

Avian influenza detection and diagnosis is comprised of a rapidly evolving combination of conventional methodologies and emerging technologies. The continued global spread of Asian H5N1 influenza virus since 2003, paired with the increasing awareness of pandemic potential, has resulted in commitment of significant resources toward improving and enhancing avian influenza (AI) virus detection tools. A choice of diagnostic technology can now be based on a combination of factors that includes fitness-for-purpose, technical ease, speed, diagnostic sensitivity, specificity, and cost. Tests for the specific diagnosis of AI virus can be divided into direct demonstration of the virus or indirect demonstration of virus exposure by detection of the specific antibody. Direct detection includes conventional culture of infectious virus, as well as the use of more rapid and cost-effective technologies that allow detection of specific viral antigens or nucleic acids. Advances in miniaturization, instrumentation, and computer analysis capabilities provide laboratories the ability to not only rapidly sub-type AI viruses, but also to rapidly perform complete genotypic and phylogenetic analysis on individual AI virus isolates. Antibody-based detection of AI virus exposure includes conventional agar-gel immunodiffusion and hemagglutination inhibition methods that have changed little since introduced decades ago, as well as advances in the well-established ELISA-based methodologies that provide on-site screening capabilities and potential for differential detection of avian influenza subtypes.

Section snippets

Clinical diagnosis

Avian influenza infection can be complicated because the virus does not cause pathognomonic lesions either grossly or microscopically. To further complicate clinical diagnosis, asymptomatic infections are especially common in waterfowl species which serve as reservoirs of the virus. Asymptomatic carriers can however shed virus that is capable of causing severe lesions in other species, in particular domestic poultry. In poultry, pathological lesions are dependent on virus subtype, virus

Virus isolation and identification

Demonstration of infectious virus by inoculation of embryonated eggs is the historic gold standard for diagnosis of avian influenza virus, and generally follows internationally recognized methods [1]. The virus is inoculated into the chorioallantoic sac and in some cases additionally into yolk sac and onto chorioallantoic membrane [14] then incubated for periods of time ranging from 24 to 48 h for HPAI virus isolates, and up to 21 days through two or three blind passages for some LPAI virus

Serologic assays

Direct detection methods using molecular techniques or antigen capture have rapidly improved and become increasingly available in the same time that relatively few changes have been made in antibody-based detection approaches. The conventional serologic techniques of agar-gel immunodiffusion and hemagglutination inhibition continue to be widely used globally for surveillance and disease control efforts in domestic poultry species [1]. A competitive ELISA (cELISA) has been described as a

Environmental sampling

For AI virus detection and diagnostic methods, specimen collection occurs at the individual bird level, though for cost efficiency and interpretation of results samples may be pooled, statistical sampling approaches applied, and the flock considered as the diagnostic unit of interest. An alternate approach for sampling to detect avian influenza virus has been proposed. Environmental air-sampling paired with realtime RT-PCR was used to detect exotic Newcastle disease virus in commercial poultry

Conclusions

Avian influenza virus is recognized as a highly mutable virus that is constantly evolving. Although the conventional methods of virus isolation, identification, and pathotyping have stood the test of time, new technologies and approaches for AI virus diagnosis also continue to evolve. Antigen detection and molecular techniques continue to speed the ability to not only detect AI virus from clinical specimens, but to provide in depth phylogenetic and pathotype information in minutes to hours. The

References (53)

  • A. Ghindilis et al.

    CombiMatrix oligonucleotide arrays: genotyping and gene expression assays employing electrochemical detection

    Biosens Bioelectron

    (2007)
  • J. Stevens et al.

    Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities

    J Mol Biol

    (2006)
  • D. Peng et al.

    Comparison of a new gold-immunochromatographic assay for the detection of antibodies against avian influenza virus with hemagglutination inhibition and agar gel immunodiffusion assays

    Vet Immunol Immunopathol

    (2007)
  • D. Deregt et al.

    A microsphere immunoassay for detection of antibodies to avian influenza virus

    J Virol Methods

    (2006)
  • Alexander DJ. Highly pathogenic avian influenza. In: Manual of standards for diagnostic tests and vaccines. World...
  • D.E. Swayne et al.

    Influenza

  • T. Songserm et al.

    Domestic ducks and H5N1 influenza epidemic, Thailand

    Emerg Infect Dis

    (2006)
  • D.J. Hulse-Post et al.

    Role of domestic ducks in propagation and biological evolution of highly pathogenic H5N1 influenza viruses in Asia

    Proc Natl Acad Sci USA

    (2005)
  • L.E. Leigh Perkins et al.

    Pathogenicity of a Hong Kong-origin H5N1 highly pathogenic avian influenza virus for emus, geese, ducks, and pigeons

    Avian Dis

    (2002)
  • H. Nakatani et al.

    Epidemiology, pathology, and immunohistochemistry of layer hens naturally affected with H5N1 highly pathogenic avian influenza in Japan

    Avian Dis

    (2005)
  • J.D. Brown et al.

    Susceptibility of North American ducks and gulls to H5N1 highly pathogenic Avian Influenza viruses

    Emerg Infect Dis

    (2006)
  • G.F. Rimmelzwan et al.

    Influenza A virus (H5N1) infection in cats causes systemic disease with potential novel routes of virus spread within and between hosts

    Am J Pathol

    (2006)
  • M. Enserink et al.

    Avian flu finds new mammal hosts

    Science

    (2004)
  • T. Kuiken et al.

    Avian H5N1 influenza in cats

    Science

    (2004)
  • T. Songsermn et al.

    Avian influenza in naturally infected domestic cat

    Emerg Infect Dis

    (2006)
  • T. Songsermn et al.

    Fatal avian influenza A H5N1 in a dog

    Emerg Infect Dis

    (2006)
  • Cited by (43)

    • Advanced nanotechnologies in avian influenza: Current status and future trends – A review

      2017, Analytica Chimica Acta
      Citation Excerpt :

      In contrast, AIV typing microarray tests can detect and provide additional information about the subtype detected in positive clinical samples compared with that obtained using real-time-PCR [20]. Lab-on-a-chip and fully integrated techniques have been developed for pathotyping and the phylogenetic characterization of influenza A viruses obtained from real samples [21]. Various types of ELISAs, including immunochromatographic strip tests [22] and double antibody sandwich enzyme-linked immune-sorbent assay (DAS-ELISA) [23], have been widely used for the rapid detection of subtype H9 influenza viruses and receptor binding specificity in different types of samples.

    • Rapid molecular haemagglutinin subtyping of avian influenza isolates by specific real-time RT-PCR tests

      2014, Journal of Virological Methods
      Citation Excerpt :

      However, virus isolation is not always possible due to either the conditions of the sample matrix or the low virus titre present in the clinical specimen (Runstadler et al., 2007). Instead, molecular HA subtyping is increasingly being performed, since it can be accomplished quickly either from a viral isolate or directly from the clinical sample (Alexander, 2008; Charlton et al., 2009). Furthermore, it allows the detection of mixed infections in one animal caused by different HA subtypes, which often remain undetected when prior virus isolation is required (Wang et al., 2008).

    • Rapid detection of avian influenza H5N1 virus using impedance measurement of immuno-reaction coupled with RBC amplification

      2012, Biosensors and Bioelectronics
      Citation Excerpt :

      For this reason, a rapid, specific and in-field method of detection for AIV H5N1 is needed. Current gold standard methods of AIV detection, viral isolation culture and rRT-PCR, are time-consuming, expensive and require special training and facilities (Charlton et al., 2009; Ellis and Zambon, 2002). Other techniques of AIV detection, such as ELISA and immunochromatographic strips, lack the specificity and sensitivity required.

    View all citing articles on Scopus
    View full text