Related Experiment Video
Updated: Jul 8, 2026
Rapid Molecular Detection and Differentiation of Influenza Viruses A and B
Published on: January 30, 2017
Avian influenza - diagnosis
1Virology Department, Veterinary Laboratories Agency Weybridge, Addlestone, Surrey, UK. d.j.alexander@vla.defra.gsi.gov.uk
Abstract:
The diagnosis of avian influenza (AI) virus infections, even highly pathogenic AI (HPAI), represents a considerable challenge due to the lack of pathognomonic or specific clinical signs and their variation in different avian hosts plus the marked antigenic variation amongst influenza A viruses. Conventional laboratory techniques involve the isolation, identification and characterization (including virulence estimates) of the virus. While this has proven successful in the past and remains the method of choice, for at least the initial outbreak, the delays associated with conventional diagnosis are often considered unacceptable for the application of control measures, especially stamping out policies, and there is an overwhelming demand for rapid results. More and more, molecular biological techniques are being used and in particular reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time RT-PCR technologies are being employed for rapid diagnosis. In this paper, clinical signs, the molecular basis for virulence of AI viruses, international definitions, conventional diagnosis and the use of molecular techniques are reviewed and discussed.
Insights
Diagnosing avian influenza (AI) in birds is challenging due to varied signs and virus changes. Rapid molecular methods like RT-PCR offer faster results than traditional techniques for better disease control.
Area of Science:
- Veterinary Virology
- Molecular Diagnostics
- Avian Health
Background:
- Avian influenza (AI) diagnosis is difficult due to non-specific clinical signs and viral variability.
- Current diagnostic delays hinder effective control measures like stamping out policies.
Purpose of the Study:
- To review clinical signs, virulence factors, and diagnostic approaches for avian influenza.
- To discuss the advantages of molecular techniques for rapid AI diagnosis.
Main Methods:
- Review of clinical signs and molecular basis of AI virulence.
- Analysis of conventional diagnostic methods (isolation, identification, characterization).
- Evaluation of molecular techniques, specifically reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time RT-PCR.
Main Results:
- Conventional AI diagnosis, while reliable, involves time-consuming steps.
- Molecular methods like RT-PCR provide significantly faster results for AI detection.
- Rapid diagnosis is crucial for timely implementation of disease control strategies.
Conclusions:
- Molecular techniques, particularly RT-PCR, are increasingly vital for rapid and accurate avian influenza diagnosis.
- The shift towards molecular diagnostics addresses the need for speed in managing AI outbreaks.
- A comprehensive understanding of AI, from clinical signs to molecular diagnostics, is essential for effective disease management.
