Development of reverse transcription loop-mediated isothermal amplification for rapid detection of H9 avian influenza virus

Evaluation of Two Commercial Loop-Mediated Isothermal Amplification Assays for Detection of Avian Influenza H5 and H7 Hemagglutinin Genes

“…LAMP primers tailored to detect with high sensitivity a limited set of, e.g., H5 isolates currently circulating in a circumscribed region are expected to yield better sensitivities. 2,5,6 In this line, it is interesting to note that for the Influenza A virus M gene, which harbors a series of highly conserved sequence stretches, a sensitive generic RT-LAMP assay was successfully developed by using degenerated primers and an amplification phase of 2 hr. 13 On the basis of this study, the real-time RT-LAMP technology using the commercial primer kits Avian Flu H5 and Avian Flu H7 is currently less suitable for generalized diagnostic approaches in the veterinary field when compared with real-time RT-PCR.…”

“…2 All clinical samples originating from a recent AIV outbreak in China and examined with this H9 subtypespecific RT-LAMP had also been virus isolation-positive, which indicates that comparatively high virus loads had been present in these samples. 2 Two H5-specific RT-LAMP assays differed very much in their sensitivities. 5,6,8 An H5N1-specific real-time RT-LAMP with a long 2-hr amplification phase revealed detection limits comparable to conventional RT-PCR for recent highly pathogenic H5N1 strains belonging to clades 1 and 2, respectively.…”

“…Concerning sensitivities of AIV subtype-specific LAMP approaches, only a few reports on H5 and 1 report on H9 have been published so far, but these focus more on the suitability for detection of a selection of very recent strains rather than a wide variety of distinct isolates. 2,5,8 Surprisingly, no data is available for the diagnosis of H7 subtype AIV RNA with the use of LAMP-based assays, although H7 AIV infections of poultry are notifiable to the O.I.E (World Organization for Animal Health). All AIV-targeted RT-LAMP assays developed so far have been compared with conventional RT-PCR, and sensitivity was calculated on the basis of infectivity, not taking into account the amount of RNA copies.…”

“…All AIV-targeted RT-LAMP assays developed so far have been compared with conventional RT-PCR, and sensitivity was calculated on the basis of infectivity, not taking into account the amount of RNA copies. 2,5,6,8 In this study, sensitivity of real-time RT-LAMP assays was compared with highly sensitive realtime RT-PCR assays, which now represent the gold standard for AIV RNA detection. 12 A conventional RT-LAMP assay developed for detection of the nucleoprotein gene of human Influenza B virus and the HA fragments of the Influenza A virus subtypes H1 and H3 was reported to be less sensitive than virus isolation but more sensitive than a commercial immunochromatography test.…”

Evaluation of the Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) as a Screening Method for the Detection of Influenza Viruses in the Fecal Materials of Water Birds

“…The loop-mediated isothermal amplification (LAMP) is one of the molecular methods to amplify the genome under isothermal conditions with high specificity, efficiency, and rapidity [20]. This method has been used for rapid detection of influenza virus genes [3,11,12,24]. In the present study, we assessed sensitivity and specificity of the reverse transcription (RT)-LAMP of influenza virus detection from fecal materials of ducks.…”