Comparison of 3 Diagnostic Tests for the Detection ofandspp. in Asymptomatic Dogs ().

Abstract

After detectingandinfections and coinfections in 2 litters of puppies in our vivarium, our team realized that we needed a simple, quick, and economical point-of-care test for concurrent screening of asymptomatic dogs for both organisms. Periodic screening of colony dogs and of all dogs introduced into a colony can prevent the spread ofandto immunologically naïve animals and help keep staff safe from these zoonotic organisms. To compare methods for diagnosingandspp. in dogs, we used a convenience sampling of feces from 2 popula- tions of dogs; samples were tested with a lateral-flow assay (QC), a commercially-available direct fluorescent assay (DFA), and an inhouse PCR test using established primers. QC results were analyzed in 2 ways: 1) relative to a reference standard that permitted comparative interpretation of DFA and PCR results; and 2) using Bayesian analysis for comparison independent of a reference standard. The QC test showed good specificity for the detection ofaccording to both the reference standard (95%) and the Bayesian analysis (98%). Similarly, specificity of the QC for the detection ofwas 95% according to the reference standard and 97% according to Bayesian analysis. However, the sensitivity of the QC test was much lower for both(reference standard, 38%; Bayesian analysis, 48%) and(25% and 40%, respectively). This study demonstrates that the QC test can be used to detect bothandin dogs and that positive results can be accepted with confidence, whereas negative tests should be confirmed through secondary testing methods.