Development of an isothermoal amplification-based assay for rapid visual detection of an Orf virus

• Published in: Virology journal 2016-03, Vol.13 (45), p.46-46, Article 46
• Main Authors: Yang, Yang, Qin, Xiaodong, Wang, Guangxiang, Jin, Jiaxin, Shang, Youjun, Zhang, Zhidong
• Format: Article
• Language: English
• Subjects: Analysis; Animals; Causes of; Complications and side effects; Diagnosis; DNA, Viral; Ecthyma, Contagious - diagnosis; Ecthyma, Contagious - virology; Gene expression; Genes, Viral; Goats; Methodology; Nucleic Acid Amplification Techniques; Orf virus - genetics; Polymerase chain reaction; Pyoderma; Reproducibility of Results; Sensitivity and Specificity
• ISSN: 1743-422X; 1743-422X
• DOI: 10.1186/s12985-016-0502-x

Orf virus (ORFV) is the causative agent of a severe infectious skin disease (also known as contagious ecthyma) in goats, sheep and other small ruminants. Importantly, ORFV also infect humans which causes a public health concern in the context of changing environment and increase in human populations. The rapid detection is critical in effective control of the disease and urgently needed. A novel "point of care" molecular amplification assay for rapid visual detection of ORFV was developed based on isothermoal recombinase polymerase amplification (RPA) technology in combination with a simpler lateral flow immunoassay strip (ORFV RPA- LFD assay). The developed ORFV RPA- LFD assay was able to detect ORFV in less than 25 min. This assay was highly sensitive, with detection limit of as low as 80 copies/reaction, and highly specific, with no cross-reactions with capripox virus, foot-and-mouth disease virus and peste des petits ruminants virus. Furthermore, the ORFV RPA- LFD assay has good correlation with qPCR assay for detection of ORFV present in clinical samples. The developed ORFV RPA-LFD assay was a sensitive and specific method for rapid detection of ORFV, and has great potential as an onsite molecular diagnostic tool in control of Orf.