Isabela Gonçalves da Silva¹, Bruno Rodrigo de Medeiros¹, Darizon Gonçalves¹, Laura Petrucci Martins¹, Amanda Gonzaga Gomes², Ketlhyn Geovana Silva Souza², Maria Luiza Andrade Araújo², Nayara Resende Nasciutti¹ and Sérgio Eustáquio Lemos da Silva^1,2*

¹Veterinary Medicine Program, Centro Universitário do Triângulo, UNITRI, Brazil
²Biomedicine Program, Centro Universitário do Triângulo, UNITRI, Brazil

*Corresponding Author: Sérgio Eustáquio Lemos da Silva, Veterinary Medicine Program, Centro Universitário do Triângulo, UNITRI, Brazil.

Received: June 17, 2026; Published: July 23, 2026

Abstract

Canine ehrlichiosis is a hemoparasitosis with significant impact on veterinary clinic and public health, caused by the obligate intracellular pathogen Ehrlichia canis and transmitted by the tick Rhipicephalus sanguineus. This study aimed to conduct a retrospective survey of cases with presumptive suspicion of ehrlichiosis treated at a private veterinary clinic in the municipality of Monte Alegre de Minas-MG, from January to December 2024, identifying the main risk factors, clinical signs, and laboratory abnormalities. The medical records of 197 dogs that presented suggestive signs and a history of exposure to the vector were analyzed. Of this total, 110 were males and 87 were females. Diagnosis was based on clinical evaluation – with main findings including apathy, vomiting, fever, anorexia, epistaxis and petechiae – and complete blood count. More than 90% of the animals evaluated presented leukocytosis, thrombocytopenia and anemia concomitantly. The therapeutic protocol established was based on the use of doxycycline associated with supportive therapy. The results revealed severe limitations in the surveillance and consolidation of local data: ethical commitments regarding the confidentiality of medical records and the absence of a unified database prevented the differentiation between new and old cases, making it impossible to determine broad population epidemiological indicators in the region. In addition, the risk of inaccurate diagnoses and false-positives resulting from the exclusive dependence of blood count in the local routine is discussed, given the lack of support from gold-standard tests, such as ELISA, CRP, or indirect immunofluorescence (IFA). It is concluded that the clinical suspicion of the disease is highly frequent in the city’s routine, a scenario aggravated by the high density of stray dogs. There is an urgent need to raise awareness among owners, implement more specific diagnostic methods and structure an efficient veterinary data storage system to enable assertive prophylactic measures in the region.

Keywords: Ehrlichia canis; Retrospective Study; Thrombocytopenia; Laboratory Screening; Suspected Cases

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Citation

Citation: Sérgio Eustáquio Lemos da Silva., et al. “Retrospective Analysis and Constraints in Epidemiological Monitoring of Canine Ehrlichiosis". Acta Scientific Microbiology 9.8 (2026): 33-40.

Copyright

Copyright: © 2026 Sérgio Eustáquio Lemos da Silva., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.