Application of qPCR method to hair and cerumen samples for the diagnosis of canine leishmaniosis in Araçatuba, Brazil

Abstract

Visceral leishmaniosis (VL) remains a serious public health problem in Brazil. Dogs are the main hosts of the parasite, developing canine leishmaniosis (CanL), hence the importance of an accurate diagnosis of the animals. Recently, the application of qPCR method to non-invasive samples obtained from dogs with CanL has shown high sensitivity. Thus, we analyzed by qPCR blood, hair (from healthy zones and cutaneous lesions) and cerumen of 16 dogs with confirmed leishmaniosis from Araçatuba, a Brazilian endemic area. Cerumen-qPCR showed the highest sensitivity (87.5%), followed by hair (lesions: 78.57%, healthy skin: 62.5%), and blood (68.75%). We also analyzed blood, hair and cerumen of 5 healthy dogs from a non-endemic area, obtaining 100% of specificity in all samples. The use of cerumen and hair for qPCR analysis provides high reliability, taking into account the sensitivity and total specificity of the method. The non-invasive sampling procedure without the need of specific conditions of storage and transport support the usefulness of hair and cerumen for the diagnosis of CanL.