Detection of canine parvovirus in fecal samples using loop-mediated isothermal amplification

Loop-mediated isothermal amplification (LAMP) is a novel, sensitive, and rapid technique for detection of genomic DNA. The end-product of the technique is a white precipitate of magnesium pyrophosphate that is visible without the use of gel electrophoresis. The LAMP method was applied to the detection of canine parvovirus (CPV) genomic DNA. A set of 4 primers, 2 outer and 2 inner, were designed from CPV genomic DNA targeting the VP2 gene. The optimal reaction time and temperature for LAMP were determined to be 60 minutes and 63°C. On the basis of results for 50 canine fecal samples using polymerase chain reaction (PCR) analysis as the gold standard, the relative sensitivity of LAMP was 100% and the relative specificity was 76.9%. The detection limit of the LAMP method was 10^-1 median tissue culture infective doses (TCID ₅₀)/ml, compared with 10 TCID₅₀/ml for PCR analysis. In addition to the advantage resulting from visual detection of the end product, the LAMP method is very rapid, requiring only 1 hour to complete. This assay would be a viable alterative to PCR analysis for diagnosis of CPV infection in dogs. The LAMP method holds promise for use as a diagnostic assay for CPV detection in a clinical setting.