Reverse-transcription recombinase-aided amplification assay for H7 subtype avian influenza virus.

Suchun Wang,Lin Zhu,Yang Wang,Qingying Fan,Xiaoguang Zhang,Xuejun Ma,Yawei Sun,Kaicheng Wang,Ping Liu,Baoxu Huang

doi:10.1111/tbed.13411

Abstract

H7 subtype avian influenza virus infection is an emerging zoonosis in some Asian countries and an important avian disease worldwide. A rapid and simple test is needed to confirm infection in suspected cases during disease outbreaks. In this study, we developed a reverse-transcription recombinase-aided amplification assay for the detection of H7 subtype avian influenza virus. Assays were performed at a single temperature (39°C), and the results were obtained within 20min. The assay showed no cross-detection with Newcastle disease virus or infectious bronchitis virus, which are the other main respiratory viruses affecting birds. The analytical sensitivity was 102 RNA copies per reaction at a 95% probability level according to probit regression analysis, with 100% specificity. Compared with published reverse-transcription quantitative real-time polymerase chain reaction assays, the κ value of the reverse-transcription recombinase-aided amplification assay in 342 avian clinical samples was 0.988 (p<.001). The sensitivity for avian clinical sample detection was 100% (95%CI, 90.40%-100%), and the specificity was 99.96% (95%CI, 97.83%-99.98%). These results indicated that our reverse-transcription recombinase-aided amplification assay may be a valuable tool for detecting avian influenza H7 subtype virus.

Highlights

Influenza A virus (IAV), a member of the genus Influenza, family Orthomyxoviridae, contains eight singlestranded negative-sense RNA segments encoding at least 10 proteins [1, 2]
In this study, we developed a reverse transcription recombinase-aided amplification (RT-RAA) assay for the detection of H5 subtype avian influenza virus (AIV)
These results indicated that our RT-RAA assay may be a valuable tool for detecting H5 subtype AIV

Summary

Introduction

Influenza A virus (IAV), a member of the genus Influenza, family Orthomyxoviridae, contains eight singlestranded negative-sense RNA segments encoding at least 10 proteins [1, 2]. The IAV member avian influenza virus (AIV) can cause avian disease and public health problems. AIV can be classified into highly pathogenic avian influenza virus (HPAIV) and low pathogenic avian influenza virus (LPAIV) based on pathogenicity in chickens. All LPAIV and HPAIV infections with H5 subtypes in poultry are notifiable to the World Organization for Animal Health [4]. Determination of the subtypes of AIV is of importance for the diagnosis of these infections, which can be achieved by analysis of the amino acid sequence of the cleavage site in the AIV hemagglutinin (HA) gene [5]. The H5 subtype avian influenza virus (AIV) has caused huge economic losses to the poultry industry and is a threat to human health. A rapid and simple test is needed to confirm infection in suspected cases during disease outbreaks

Methods

Results

Conclusion