Investigation of canine visceral leishmaniasis in a non-endemic area in Brazil and the comparison of serological and molecular diagnostic tests

• Published in: Revista da Sociedade Brasileira de Medicina Tropical Vol. 54; p. e01822021
• Main Authors: Sevá, Anaiá da Paixão, Brandão, Ana Pérola Drulla, Godoy, Silvia Neri, Soares, Rodrigo Martins, Langoni, Helio, Rodrigues, Bruna Cristine, Gava, Mariana Zanchetta e, Zanotto, Paula Ferraz de Camargo, Jimenez-Villegas, Tatiana, Hiramoto, Roberto, Ferreira, Fernando
• Format: Journal Article
• Language: English; Portuguese
• Published: Sociedade Brasileira de Medicina Tropical - SBMT 01.01.2021; Sociedade Brasileira de Medicina Tropical (SBMT)
• Subjects: Cãoservação Program; Dog; DPP®-Dual Path platform; ELISA; IFA; Major; Seroprevalence; TROPICAL MEDICINE; DPP®-Dual Path platform; Cãoservação Program; IFA; Dog; Seroprevalence; ELISA
• ISSN: 0037-8682; 1678-9849; 1678-9849
• DOI: 10.1590/0037-8682-0182-2021

INTRODUCTIONVisceral leishmaniasis (VL) is an important zoonosis in Brazil. Previous identification of parasitized dogs can also help prevent the disease in humans, even in non-endemic areas of the country. The Brazilian Ministry of Health recommends diagnosis in dogs using a DPP® (rapid test) as a screening test and an immunoenzymatic assay (ELISA) as a confirmatory test (DPP®+ELISA), and culling infected dogs as a legal control measure. However, the accuracy of these serological tests has been questioned. METHODSVL in dogs was investigated in a non-endemic area of the São Paulo state for three consecutive years, and the performances of different diagnostic tests were compared. RESULTSA total of 331 dog samples were collected in 2015, 373 in 2016, and 347 in 2017. The seroprevalence by DPP®+ELISA was 3.3, 3.2, and 0.3%, respectively, and by indirect immunofluorescence assay (IFA), it was 3.0, 5.6, and 5.5%, respectively. ELISA confirmed 18.4% of DPP® positive samples. The concordance between the IFA and DPP® was 83.9%. The concordance between IFA and DPP®+ELISA was 92.9%. A molecular diagnostic test (PCR) was performed in 63.2% of the seropositive samples, all of which were negative. CONCLUSIONSIn non-endemic areas, diagnostic tests in dogs should be carefully evaluated to avoid false results.