Canine parvovirus type 2 (CPV-2), including types 2b and 2c, causes an acute enteric disease in both domestic and wild animals. Rapid and sensitive diagnosis could aid effective disease management at points of need (PON). Working with insulated isothermal PCR (iiPCR), the field-deployable and user-friendly POCKIT^TM system displays excellent sensitivity and specificity for nucleic acid detection (1, 2). An iiPCR-POCKIT^TM method was developed and evaluated for CPV-2 detection. The CPV-2 iiPCR was designed to detect all circulating CPV-2 strains. Limit of detection (LoD) was determined using plasmid DNA. Seven canine pathogens were tested to evaluate exclusivity. Assay sensitivity and performance were compared with an in-house real-time PCR (qPCR, University of Tennessee Veterinary Medical Center). Sensitivity comparison was performed using a CPV-2b strain. Performance comparison was done using 101 fecal samples submitted to the UTVMC from 2010 to 2014 (including CPV and feline panleukopenia strains). The 95% LoD of iiPCR was 13 copies of plasmid DNA and detection limits for dilutions of CPV-2b DNA were equivalent for the iiPCR and qPCR methods. Non-targeted pathogens were not detected (Table 1). Test results of 99 fecal samples by qPCR and iiPCR agreed with each other, while two qPCR-positive samples tested negative by iiPCR (Table 2), demonstrating excellent agreement (k = 0.96) with sensitivity of 96.88% and specificity of 100%. The iiPCR- POCKIT^TM system detected CPV-2 in feces with sensitivity and specificity equivalent to the qPCR. This system has potential to serve a useful tool for rapid and accurate PON, molecular detection of CPV-2.

Table 1. CPV POCKIT^TM iiPCR did not detect other non-targeted canine pathogens

Table 2. A 2 x 2 contingency table summarizing analysis results of 101 faecal samples for CPV-2 by qPCR and iiPCR