Evaluation of a novel chromatographic immunoassay based on Dual-Path Platform technology (DPP® CVL rapid test) for the serodiagnosis of canine visceral leishmaniasis.

Canine visceral leishmaniasis (CVL) is the major source of human visceral leishmaniasis (VL) and is transmitted from dogs to sand flies to humans. To control the spread of this disease, early and accurate detection of infected dogs is critical but challenging. Here we demonstrate the potential of the Dual-Path Platform (DPP(®)) CVL rapid test for detecting K26/K39-reactive antibodies in sera from clinically symptomatic (n=60) and asymptomatic (n=60) Leishmania infantum-infected dogs. For the specificity evaluation, assays were performed using known negative diagnostic serum samples (n=59) and cross-reaction control sera (n=11) from animals born in a VL-free area of Brazil. The diagnostic kit displayed high specificity (96%) but low sensitivity (47%) in identifying parasite-positive dogs without signs of CVL. However, the test sensitivity was significantly higher (98%) in diseased cases, indicating that this convenient test may be useful to identify the most infectious dogs. Efforts should be pursued to obtain a more sensitive DPP-multiplexed test parameter (i.e. based on simultaneous yet separate antibody detection of carefully selected multiple antigens of diagnostic utility) for effective serodiagnosis of early-infected dogs, as this will likely allow more efficient canine removal regimens than those used in practice by public health services.