Development of multiplex rt-PCR assays for rapid detection and subtyping of influenza type A viruses from clinical specimens.

College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Korea.
Journal of Microbiology and Biotechnology (Impact Factor: 1.32). 07/2008; 18(6):1164-9.
Source: PubMed

ABSTRACT We developed multiplex RT-PCR assays that can detect and identify 12 hemagglutinin (H1-H12) and 9 neuraminidase (N1-N9) subtypes that are commonly isolated from avian, swine, and human influenza A viruses. RT-PCR products with unique sizes characteristic of each subtype were amplified by multiplex RT-PCRs, and sequence analysis of each amplicon was demonstrated to be specific for each subtype with 24 reference viruses. The specificity was demonstrated further with DNA or cDNA templates from 7 viruses, 5 bacteria, and 50 influenza A virus negative specimens. Furthermore, the assays could detect and subtype up to 105 dilution of each of the reference viruses that had an original infectivity titer of 106 EID50/ml. Of 188 virus isolates, the multiplex RT-PCR results agreed completely with individual RT-PCR subtyping results and with results obtained from virus isolations. Furthermore, the multiplex RT-PCR methods efficiently detected mixed infections with at least two different subtypes of influenza viruses in one host. Therefore, these methods could facilitate rapid and accurate subtyping of influenza A viruses directly from field specimens.

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    ABSTRACT: Avian Influenza (AI), Newcastle Disease (ND) and Infectious Bursal Disease (IBD) are highly contagious diseases with high occurrence in poultry. These 3 viral diseases are a major cause of disease problems in the poultry industry in Indonesia. The classical methods for detection and characterization of the etiological agents are by clinical sign, serological test, immunodiffusion test, pathology, histopathology and virus isolation. Since these conventional laboratory method have low sensitivity and specificity, the rapid diagnostic tool based on molecular technique are needed. Rapid detection and differential diagnosis for viral diseases have an important implication in clinical, economical and epidemiological aspects. RT-PCR amplification for diagnosis of viral disease in poultry industry is common used. This method can detect virus as etiological agent in poultry disease. Multiplex RT-PCR involves simultaneous amplification of more than one infectious agent using more than primer pair. In the present study, we developed a single step multiplex RT-PCR method, which can help in rapid detection and differentiation viruses as an etiological agent of AI, ND and IBD diseases. The method is highly sensitivity, specificity, fast and less expensive. The results showed that the single step multiplex RT-PCR method has been developed to rapid detection and differential diagnose for AI, ND and IBD viruses simultaneously in one step amplification reaction. This method is simple and easy for laboratory diagnosis application as well as specific and efficient to diagnose of viral diseases in poultry
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