Molecular study of Canine monocytic Ehrlichiosis in the City of Machala, Ecuador

• Stalin Yhovanny Correa–Vivanco Universidad Técnica de Machala, Programa de Maestría en Medicina Veterinaria. Machala, El Oro, Ecuador
• Ana Elizabeth Guerrero–López Universidad Técnica de Machala, Programa de Maestría en Medicina Veterinaria. Machala, El Oro, Ecuador - Universidad Técnica de Machala, Facultad de Ciencias Agropecuarias, Escuela de Medicina Veterinaria. Machala, El Oro, Ecuador
• Lorena Elizabeth Chalco–Torres Universidad Técnica de Machala, Facultad de Ciencias Agropecuarias, Escuela de Medicina Veterinaria. Machala, El Oro, Ecuador
• Robert Gustavo Sánchez Prado Universidad Técnica de Machala, Facultad de Ciencias Agropecuarias, Escuela de Medicina Veterinaria. Machala, El Oro, Ecuador
• Mauro Nirchio–Tursellino Universidad Técnica de Machala, Facultad de Ciencias Agropecuarias, Escuela de Medicina Veterinaria. Machala, El Oro, Ecuador

DOI: https://doi.org/10.52973/rcfcv-e34378

Keywords: Ehrlichia canis, Rhipicephalus sanguineus, canines, PCR, immunochromatography

Abstract

Canine Monocytic Ehrlichiosis (CME), an emerging disease caused by Ehrlichia canis. This pathogen is commonly found in dogs and other wild canids acting as natural reservoirs. CME is prevalent in tropical and subtropical regions, due to the presence of the brown dog tick, Rhipicephalus sanguineus, which acts as the main vector, with Latin America being an affected region. The disease manifests in three clinical stages: acute, subclinical, and chronic, with symptoms such as depression, lethargy, anorexia, hemorrhages, and changes in hematological parameters. The diagnosis of E. canis can be made through serological and molecular tests, with PCR targeting the 16S rRNA gene considered the most reliable technique. The study was conducted on dogs with clinical symptoms at a veterinary clinic in Ecuador. Immunochromatographic tests and polymerase chain reaction were performed to identify the presence of E. canis. It was evident that serological tests have a higher positivity rate but can generate false positives due to post–infection time. PCR allows early detection, even in subclinical phases, offering the possibility of starting treatment before the manifestation of symptoms. It is concluded by emphasizing the importance of performing a combination of laboratory tests for a more reliable diagnosis of CME in dogs, identifying dogs early as possible sources of zoonotic transmission of E. canis to humans.

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