Leishmania, Babesia and Ehrlichia in urban pet dogs: co-infection or cross-reaction in serological methods?

Abstract

Introduction:The present study was designed to assess the occurrence of co-infection or cross-reaction in the serological techniques used for detecting the anti-Leishmania spp., -Babesia canis vogeli and -Ehrlichia canis antibodies in urban dogs from an area endemic to these parasites. Methods: The serum samples from dogs were tested for the Babesia canis vogeli strain Belo Horizonte antigen and Ehrlichia canis strain São Paulo by immunofl uorescence antibody test (IFAT) and by antiLeishmania immunoglobulin G (IgG) antibody detection to assess Leishmania infection. We used the following four commercial kits for canine visceral leishmaniasis: ELISA, IFAT, Dual Path Platform (DPP) (Bio Manguinhos®/FIOCRUZ/MS) and a rK39 RDT (Kalazar Detect Canine Rapid Test; Inbios). Results: Of 96 serum samples submitted to serological assays, 4 (4.2%) were positive for Leishmania as determined by ELISA; 12 (12.5%), by IFAT; 14 (14.6%) by rK39 RDT; and 20 (20.8%), by DPP. Antibodies against Ehrlichia and Babesia were detected in 23/96 (23.9%) and 30/96 (31.2%) samples, respectively. No signifi cant association was identifi ed between the results of tests for detecting Babesia or Ehrlichia and those for detecting Leishmania (p-value>0.05). Conclusions: In the present study, we demonstrated co-infection with Ehrlichia or Babesia and Leishmania in dogs from Minas Gerais (Brazil); we also found that the serological tests that were used did not cross-react.

Validation of the Dual-path Platform chromatographic immunoassay (DPP® CVL rapid test) for the serodiagnosis of canine visceral leishmaniasis

“…A comprehensive assessment of possible cross-reactivity, which the method is subject to, is also suggested. (34) The results in the literature are still contradictory, presenting studies that did not observe cross-reactivity (24,44) as well as surveys that demonstrated cross-reactivity with canine babesiosis (25) and Leishmania braziliensis. (17) Ultimately, Schubach et al (32) used data from one of the cities enrolled in our four-city study (namely, Fortaleza) to evaluate the performance of the rapid test and found comparable accuracy values using whole blood and serum samples through electronic or visual readings.…”

Dogs with divergent serology for visceral leishmaniasis as sources of Leishmania infection for Lutzomyia longipalpis phlebotomine sand flies – an observational study in an endemic area in Brazil

“…Unfortunately, alternative methods with higher sensitivity and specificity, at affordable costs for public health services, are still unavailable [20,42]. Coinfection or crossreaction with Babesia canis and Ehrlichia canis in dogs from urban endemic or non-endemic areas for CVL were shown to interfere with the serological diagnosis of CVL [32,[43][44][45]. Serological cross-reaction was also observed with Trypanosoma cruzi, which belongs to the same Trypanosomatidae family as Le.…”

Early antibody response and clinical outcome in experimental canine leishmaniasis

“…The main drawback of most cross-sectional studies relates to the potential cross-reactivity with other pathogens frequently coinfecting dogs ( Babesia , Ehrlichia , Neospora , Toxoplasma ) 33,34 and the lack of information on the actual time elapsed after inoculation. These limitations could be overcome by analyzing experimentally infected animals to determine early infection markers and, potentially, the value of the reactivity pattern of WB for clinical follow-up.…”