title: Development of a loop-mediated isothermal amplification assay combined with a lateral flow dipstick for rapid and simple detection of classical swine fever virus in the field.
abstract: Classical swine fever (CSF) is a highly contagious viral disease and may cause heavy economic loss to farmers. The rapid, simple and accurate diagnosis of the disease at the frontline, for example on the farms of concern is crucial for disease control. This study describes the development and evaluation of a new loop-mediated isothermal amplification (LAMP) assay coupled with lateral flow dipstick (LFD) for the detection of classical swine fever virus (CSFV). This RT-LAMP-LFD assay combines the efficient one-step isothermal amplification of CSF viral RNA and the simplicity of the LFD to read the results within two to five minutes. Seven genotypes (1.1, 1.2, 1.3, 2.1, 2.2, 2.3 and 3.1), but not genotype 3.4, were successfully detected by the RT-LAMP-LFD assay, indicating that the method has a broad range of detection and can be applied in different geographical areas where CSFV strains belonging to these genotypes are present. The performance of this RT-LAMP-LFD assay was similar to that of the real-time RT-PCR. The analytical sensitivity was about 100copies per reaction when testing two genotypes (1.1 and 2.3). No cross-reactivity to non-CSFV pestiviruses was observed. This RT-LAMP-LFD assay can be a useful novel tool for the rapid, simple and economic diagnosis of classical swine fever in the field.
authors.affiliation: Department of Virology, Immunobiology and Parasitology, National Veterinary Institute, Uppsala, Sweden.
authors.forename: Vinay Kumar
authors.initials: VK
authors.lastname: Chowdry
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.
authors.forename: Yuzi
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Department of Virology, Immunobiology and Parasitology, National Veterinary Institute, Uppsala, Sweden.
authors.forename: Frederik
authors.initials: F
authors.lastname: Widén
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.
authors.forename: Hua-Ji
authors.initials: HJ
authors.lastname: Qiu
authors.affiliation: Key Laboratory of Preventive Veterinary Medicine of Shandong Province, Qingdao Agricultural University, Qingdao, China.
authors.forename: Hu
authors.initials: H
authors.lastname: Shan
authors.affiliation: Department of Virology, Immunobiology and Parasitology, National Veterinary Institute, Uppsala, Sweden.
authors.forename: Sándor
authors.initials: S
authors.lastname: Belák
authors.affiliation: Department of Virology, Immunobiology and Parasitology, National Veterinary Institute, Uppsala, Sweden. Electronic address: Lihong.Liu@sva.se.
authors.forename: Lihong
authors.initials: L
authors.lastname: Liu
mesh_terms: D000818:Animals; D002846:Chromatography, Affinity / Q000379:methods*; D006691:Classical Swine Fever / Q000175:diagnosis*; D006692:Classical Swine Fever Virus / Q000235:genetics / Q000302:isolation & purification*; D003429:Cross Reactions; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D012680:Sensitivity and Specificity; D013552:Swine; D013997:Time Factors; D014730:Veterinary Medicine / Q000379:methods*
keywords: Classical swine fever virus; Field diagnosis; Lateral flow dipstick; Molecular detection; RT-LAMP