Adaptation of an Invader ® assay for the detection of African swine fever virus DNA

• Published in: Journal of virological methods Vol. 124; no. 1; pp. 1 - 10
• Main Authors: Hjertner, Bernt, Meehan, Brian, McKillen, John, McNeilly, Francis, Belák, Sándor
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 01-03-2005; Amsterdam Elsevier; New York, NY
• Subjects: African swine fever virus; African Swine Fever Virus - genetics; Base Sequence; Biological and medical sciences; Diagnosis; DNA, Viral - analysis; Fundamental and applied biological sciences. Psychology; Invader squared assay; Isothermal amplification; Microbiology; Molecular Sequence Data; PCR; Polymerase Chain Reaction - methods; Sensitivity and Specificity; Techniques used in virology; Virology; African swine fever virus; Diagnosis; Invader squared assay; Isothermal amplification; PCR; Microbiology; Method; Virology; Virus; Amplification; Polymerase chain reaction; Veterinary; Detection; Adaptation
• ISSN: 0166-0934; 1879-0984
• DOI: 10.1016/j.jviromet.2004.10.009

A closed tube isothermal Invader
® assay (Third Wave Technologies Inc., Madison, Wisconsin, USA) was adapted for the detection of African swine fever virus (ASFV) DNA. Several ASFV Invader
® assays were designed successfully and tested on a real-time PCR instrument (iCycler™, BioRad). The assay exhibiting the lowest signal/noise ratio (VP73 ASFV Invader
® Assay) was analysed further using serial 10-fold dilutions of Lisbon 60 ASFV viral genome. The assay sensitivity was determined to be in the order of 2500 copies of ASFV DNA and showed a dynamic range of 4
logs, from 2.5
×
10
6 to 2500 copies. The high specificity of the test was demonstrated by the lack of cross-reactivity to the clinically similar but heterologous virus, classical swine fever virus. The sensitivity of the Invader
® assay is sufficient for the testing of acutely infected viremic animals in which the viral load will be high. The robustness and ease of use of the ASFV Invader
® assay, combined with the possibility to run and read the assay using simple and relatively inexpensive equipment, makes it suitable for laboratories lacking containment facilities and/or real-time PCR instrumentation or on a regional basis for on-site diagnosis close to putative sites of ASFV outbreaks.